Introducing our innovative and affordable CMC system that delivers high-temperature performance tailormade for heat shield applications, spanning numerous sectors. Engineered for minimal mechanical loading, ThermaLite provides reliable and long-lasting even in the most extreme thermal conditions.

ThermaLite

IgniShield is a step change in the capability of thermal protection. This CMC is made by impregnating woven Basalt fibers with HTMS’s proprietary matrix. This solution is designed to excel in fire, smoke, and toxicity applications spanning sectors such as automotive, aerospace, and energy.

IgniShield

HTMS has developed a novel CMC material that possesses a low dielectric constant even in high-temperature environments. This is the result of integrating advanced fibers into our state-of-the-art matrix system and optimising the chemistry within the entire system.  

KappaCera

High-Temperature Low Dielectric Composite

HTMS’s exploratory approach involves integrating high-strength Carbon fibres into our advanced matrix system, which expands the operational limits of Carbon-fibre based systems far beyond their current temperature capabilities. 

CarboniteX

Oxide fibres for Ceramic Matrix Composites (CMCs) have been a key part in advancing materials science, particularly for applications requiring high temperature stability and oxidation resistance. These fibres are integral in reinforcing ceramic matrices, enhancing mechanical properties, and expanding the usability of composites under extreme environmental conditions. The development of oxide fibres began in the 1970s as researchers sought materials that could exceed the performance limitations of metals and non-oxide ceramics in high temperature environments. Initial efforts focused on alumina and silica-based fibres due to their inherent stability in oxidative atmospheres and capability to withstand high temperatures without significant degradation.

One significant milestone in this field was the development of Nextel™ fibres by 3M, introduced in the late 1980s. These fibres, composed of alumina, silica, and boria (Al2O3-SiO2-B2O3), marked a significant advancement due to their enhanced thermal stability and mechanical strength. Nextel™ fibres have since been widely adopted in various high temperature applications, from aerospace to defence, for their ability to maintain integrity under thermal stresses whilst resisting corrosive environments. The 1990s brought further innovations with the introduction of stoichiometric mullite in alumina fibres (3Al2O3 2SiO2). These fibres offered improved toughness and thermal shock resistance over pure alumina fibres, making them more suitable for the dynamic thermal environments that products experience in aerospace and land-based energy applications. This period also saw significant advancements in the processing techniques of oxide fibres, notably through sol-gel and dry spinning methods, which improved the uniformity and quality of the fibres.

In the early 2000s, the focus shifted towards optimising the cost-effectiveness and engineering flexibility of oxide fibres. The adoption of fibres with higher denier and modifications in fibre chemistry to include rare earth elements exemplified efforts to enhance performance characteristics such as creep resistance and thermal stability. These enhancements have broadened the applicability of oxide CMCs, pushing them towards more mainstream adoption in various industrial sectors. Recent developments have concentrated on refining the properties of oxide fibres to meet the specific demands of advanced applications. Innovations in fibre architecture and composite processing techniques have enabled the development of CMCs that can perform under greater thermal and mechanical loads. The ongoing research aims to further reduce costs and improve the performance of oxide CMCs, ensuring their competitive advantage over traditional materials such as titanium and other high-temperature alloys.

This section delves into the three predominant fibre types typically used for CMCs —oxide fibres, carbon fibres, and silicon carbide (SiC) fibres — each offering unique properties that cater to specific demands and requirements.

As discussed, oxide fibres, such as alumina and mullite, are renowned for their high temperature stability, making them ideal for challenging thermal environments. They exhibit excellent resistance to oxidation, crucial for applications that are exposed to an oxygen-rich atmospheres at elevated temperatures. Additionally, these fibres are generally less expensive compared to other high performance fibres like SiC, providing a more cost-effective solution for various applications. However, they typically have lower strength and stiffness and are susceptible to creep under high temperature stress, which may limit their use in load-bearing applications.

Specific types of oxide fibres include Nextel 610 from 3M, which is favoured for its high alumina content and suitability for high-temperature applications due to excellent resistance to thermal shock and oxidation. Nextel 720 offers lower strength but higher thermal stability, ideal for higher temperature environments, while Nextel 312 and 440 offer a range of properties tailored to specific needs from automotive to aerospace, where cost and thermal performance are pivotal.

Hiltex's development in continuous alumina-silica fibres stands out through its utilisation of dry spinning technology, paired with an extensive background in fibrous refractory manufacturing. The resulting HILTEX ALF fibres are comprised solely of alumina (Al2O3) and silica (SiO2), making them stable oxide fibres. These fibres are notable for their fine filament diameter (7-10 microns), which enhances their flexibility and strength, characteristics often compromised in other high performance fibres due to the inclusion of materials like boron. ALF fibres exhibit excellent chemical resistance, thermal shock resistance, and electrical insulation properties. They are available in various alumina-silica ratios, with the highest grade fibres resistant to temperatures up to 1395°C. The cost of oxide fibres typically ranges from $50 to $250 per kilogram.

Carbon fibres are known for their excellent tensile strength and stiffness, making them indispensable in structural applications requiring lightweight composite materials. They can withstand very high temperatures, over 2000°C in inert environments, making them suitable for space and specialist military applications. Despite their advantages, carbon fibres rapidly lose strength in oxidising atmospheres above 500°C, which significantly limits their applications for high temperature composite materials. Polyacrylonitrile (PAN) based fibres like Toray’s T300 are widely used in aerospace and automotive sectors for their strength, while pitch-based fibres are chosen for applications that require exceptional rigidity and thermal conductivity. Carbon fibres typically range from $20 to over $500 per kg, depending on the fibre’s modulus and intended application.

SiC fibres are exceptional in preserving their strength and stiffness at temperatures that surpass the limits of both oxide and carbon fibres. These fibres offer excellent resistance to chemical attack and oxidation, making them suitable for use in harsh environments at over 1300°C. They provide a good balance of mechanical properties, including high strength, stiffness, and thermal conductivity, making them favoured for advanced applications in defence and aerospace. However, the complex production process for SiC fibres makes them one of the most expensive fibre types available, limiting their use to high-value applications. Like many ceramic materials, SiC fibres can be brittle, which may limit their use in applications requiring high impact resistance. SiC fibres are generally priced from $200 to over $1000 per kilogram, reflecting their superior properties and the complexities of their production process.

The development of new ceramic fibres plays a pivotal role in defining the capabilities and applications of CMCs. This section explores the recent advancements in oxide fibres introduced by three significant players in the market: RATH Group, Saint-Gobain Advanced Ceramic Composites, and Vulcan Shield Group.

The RATH Group, headquartered in Vienna, Austria, is known for its extensive experience in refractory materials. The company has recently completed the development of continuous oxide ceramic fibres and is due to ramp up production over the coming years. This move is set to diversify the current market, which has been largely dominated by 3M with its Nextel range of fibres. RATH's new fibres aim to match or exceed the performance characteristics of the Nextel offerings, particularly in terms of high temperature stability and creep resistance. RATH is producing alumina-based fibres (Al2O3) and mullite fibres, a blend of alumina and silica (SiO2). RATH’s focus on continuous fibre technology marks a significant step forward from the more commonly produced short fibres, offering potential for more robust and versatile CMCs.

Saint-Gobain Advanced Ceramic Composites, based France, represents a transformation from its quartz fibre production to a broader advanced ceramic composite focus. This transition is part of its strategy to break into the alumina fibre market, currently expanding its product base to include continuous alumina and mullite ceramic fibres. These fibres are designed to offer superior thermo-mechanical resistance and stability up to 1200°C, pushing the boundaries of current oxide fibre capabilities. Saint-Gobain's innovation extends to its cooperative development strategies, such as its partnership with the Denkendorf Institute for Textile and Fiber Research (DITF) in Germany. This collaboration has culminated in the development of fibres that not only compete with but also aim to surpass the performance of established products like 3M’s Nextel series. Saint-Gobain’s new fibres enhance high temperature applications by providing better dielectric properties and mechanical strength, making them suitable for aerospace and defence applications that demand lightweight yet durable materials.

Vulcan Shield Group’s (VSG) 2024 Product Catalogue introduces an array of alumina continuous fibres, highlighting their capability to operate under extreme temperatures (1200 - 1300°C) and their significant oxidation and corrosion resistance. VSG's fibres are differentiated by their alumina content, with variants ranging from 72% to 99% alumina. VSG’s alumina fibres, particularly the M-99 series with over 99% alumina content, may offer a good balance of interfacial control, high-temperature strength, and corrosion resistance. This makes them ideally suited for both metal and ceramic matrix composites and other high temperature applications. VSG’s focus on customisability and scalability in production reflects a keen responsiveness to market needs, positioning their fibres as versatile and competitive options in the global CMC market.

“The development of new ceramic fibres by RATH, Saint-Gobain, and Vulcan Shield Group signifies a significant shift in the Oxide CMC landscape. These advancements not only enhance the performance parameters of ceramic fibres but also increase competition in the market, expanding their applicability across many more applications. Historically dominated by 3M, whose Nextel fibres have set industry standards for years, the market is poised for transformation as these new entrants introduce potentially competitive alternatives. This increase in competition is likely to exert downward pressure on prices, making high performance alumina-based fibres more accessible and affordable. The broadened availability and potentially lower cost of oxide fibres could accelerate adoption and innovation, expanding the use of CMCs in both traditional and new applications.”

High Temperature Material Systems Limited (HTMS), established in 2021 by Dr. Danilo Di Salvo and Dr. Richard Grainger, is at the forefront of developing innovative CMCs for cost sensitive sectors. Leveraging advanced research and development capabilities, HTMS is committed to pioneering new matrix chemistries that enhance performance, durability, and functionality of CMCs. Their unique proprietary matrix system is distinguished by its low temperature processing capabilities, which not only reduce CO2 emissions by approximately 50% compared to traditional oxide CMC systems but also prevent damage to sensitive fibres that cannot withstand high temperatures.

This innovative approach allows HTMS to utilise a wide range of fibres previously unsuitable for CMCs due to processing constraints. By incorporating such fibres, HTMS can offer customised solutions tailored to the specific needs of their customers while circumventing the need for more costly, conventional fibres. For instance, basalt fibres, which would typically be damaged in high temperature sintering processes, are used effectively by HTMS to create cost efficient fire, smoke, and toxicity (FST) shields. HTMS's method has demonstrated that these basalt fibre based composites show minimal degradation even when tested at temperatures as high as 800°C. The affordability of basalt fibres, in comparison to traditional oxide fibres, presents a significant cost advantage, enabling HTMS to deliver high performing, lower cost CMCs to their customers.

Furthermore, HTMS has successfully produced CMCs utilising a variety of other fibres, including glass, carbon, and mineral fibres, all of which offer customisable properties to meet diverse application requirements. This flexibility in fibre selection underscores HTMS’s ability to innovate within the CMC industry, providing versatile, high quality solutions that address both performance and budgetary constraints of their clients.

In conclusion, the development of new ceramic fibres by RATH, Saint-Gobain, and Vulcan Shield Group marks a significant transformation in the oxide CMC landscape, enhancing the performance parameters of ceramic fibres and broadening their applicability across various industries. Traditionally dominated by 3M, whose Nextel fibres have set industry standards for years, the market is poised for a shift as these new players introduce competitive alternatives. HTMS also emerges as a key innovator, leveraging unique low-temperature processing techniques to utilise a wider range of fibres and provide cost-effective, tailored solutions. This burgeoning competition is expected to drive down prices, making high performance ceramic composites more accessible and cost effective. As these new products enter the market, they promise to elevate the material standards for CMCs, fostering innovation in sectors that rely on high durability and exceptional thermal resistance, and potentially disrupting 3M's long standing market dominance.

Fibres for Oxide-based Ceramic Matrix Composites

Fire-Resistant Materials for Lithium Battery Enclosure

Lithium batteries are becoming ubiquitous in our daily lives. From our phones and laptops, scooters, cars and planes, to powering the very homes we live in, high-density electrical storage is dominated by Lithium-based chemistries. While the perceived risk from these devices is generally low, there is increasingly unease about the safety of some of these systems where performance is being pushed to the limit, and the capability of the enclosures has to keep up. While rare, the extreme heat caused by battery fires can cause serious risk to human life if the materials are not developed which can withstand and contain failures to allow emergency procedures to take over.

 Transport industries have long been exploring energy storage systems to provide power and backup support to critical equipment. From the era of Lead-Acid batteries to the evolution of Nickel-Cadmium batteries, there has been a continuous pursuit of battery systems with higher power and energy density to meet the industry's evolving needs.

A step change came in the form of Lithium-Ion battery chemistry, commercially introduced by Sony in 1991. This chemistry promised a 4 to 5 times improvement in energy/power density, with approximately half the size and weight compared to alternatives. However, at that time it was already known that there was a potential risk in using these high-energy systems. The recall of MOLI’s Li-metal rechargeable cells some years before the release of rechargeable metal anode-based lithium batteries was a reminder of these risks. Early Li-Ion battery systems experienced highly publicized commercial failures, such as the Samsung Note 7 battery fiasco in 2016, caused by manufacturing defects lead to significant public scepticism. The aerospace industry has also faced similar challenges, with the FAA reporting 470 aviation-related incidents involving lithium batteries from March 3, 2006, to December 28, 2023. Notable aviation incidents, like the Ethiopian Airways 787 fire at Heathrow Airport in 2013 and the Japan Airlines 787 at Boston Airport the same year, heightened consumer awareness and prompted safety regulations to better understand the performance and limitations of Li-Ion cells and batteries.

These efforts have led to the introduction of new approaches to mitigate the thermal reactivity of Li-Ion products. Furthermore, military and regulatory agencies have implemented new Minimum Operating Performance Standards (MOPS), such as RTCA DO-311A and MIL-PRF-29595A, offering clear guidance on the development, testing, and certification requirements for Lithium-Ion battery systems.

In the search for lower costs and higher energy densities the materials and manufacturing methods become more critical. With a separator thickness of only 20–25 µm, any small intrusion of metallic dust or other particles can have devastating consequences. Whereas a nail penetration test could be tolerated on the older 18650 cell with a capacity of 1.35 Ah, today's high-density cells with >2.4 Ah would react with fire and material release when performing the same test. Lithium-ion batteries are nearing their theoretical energy density limit and battery manufacturers are stepping up their efforts to focus on improving manufacturing methods and increasing safety.

There are a number of risks posed by these higher energy-dense batteries which need to be carefully considered.

Overcharging poses a significant risk to rechargeable lithium batteries, distinct from nickel-cadmium or lead-acid batteries. This risk may result in thermal runaway, where overcharging leads to an uncontrolled increase in temperature and pressure. Additionally, overcharging can impact internal cell components, emphasizing the importance of considering battery capacity, not just size, due to the higher amount of electrolyte and energy involved.

Over-discharging is another concern, particularly for certain types of batteries discharged beyond a specific voltage, typically 2.4 volts. This can lead to corrosion of electrodes within the cells. Recharging damaged rechargeable lithium batteries, following over-discharging, may trigger an uncontrollable exothermic reaction. Corroded electrodes can themselves become a source of short circuits (see image), with a dendrite of corrosion growing from one electrode towards the other, resulting in an internal short.

Internal short circuits present a risk attributed to various factors, including manufacturing defects, impurities, and foreign object deposits. The occurrence of an internal short circuit may lead to an uncontrolled increase in temperature and pressure, ultimately resulting in thermal runaway.

Furthermore, the possibility of reverse voltage in non-rechargeable lithium batteries, especially those with more than one cell, is an important concern. This can even lead to a thermal runaway event, posing additional risks associated with uncontrolled temperature and pressure increase.

Although there many risks associated with lithium batteries, as discussed, due to their clear advantages there is a need to alleviate these so as to maintain or even increase performance. There are many methods to reducing these risks, including by software (monitoring), electronic hardware (BMSs, temp sensors, fuses), structural design (keep batteries away from key systems), early warning systems (fire/smoke detectors), and by using materials with greater fire resistance.

In the current article there is a focus on the materials used for enclosures, what makes a safe enclosure, and how we test for suitable materials for the job.

While fire resistance is an extremely complex area, it can be broken down into a number of individual measures. This is by no means an exhaustive list, for further information, please consult the further reading found in the Resources at the end of this article.

Ignition is the start of a fire, and thus the ‘ignitability’ of a material is the general term given to a materials ability to support combustion when exposed to a naked flame under normal atmospheric conditions. This definition is contested, however, with technical and general definitions overlapping and, in some cases, contradicting. The BS 476 suite of standards laid out by the British Standards Institute dictates fire tests for materials used in the construction industry, but due to their pre-existing standards have become common throughout engineering, and contains a number of tests for determining ignitability, eg BS 476-13:1987. A materials ability to ignite under these condition is a combination of its fundamental properties, and as such some materials may not be ignitable but still be able to support fire in later stages, when conditions such as temperature and reactant availability have changed. Materials which are unable to support combustion under any circumstances are considered to be non-combustible.

The term ‘combustibility’ refers to the tendency of a substance to burn as a result of fire or chemical reaction. It is can be expressed as a property that is a measure of how easily a substance will ignite or burn, an important consideration when materials are being used or stored for construction purposes. The term ‘flammable’ may be used to describe substances that ignite more easily, whilst substances that are harder to ignite or that burn less intensely may be referred to as combustible. Less combustible materials may be described as 'materials of limited combustibility'. At the extreme end of the scale is ‘non-combustible materials’ which do not support fire at all.

Some common definitions of  ‘non-combustible materials’:

Any material which when tested to BS 476-11:1982 (2007) does not flame nor cause any rise in temperature on either the centre (specimen) or furnace thermocouples.

Products classified as non-combustible in tests following the procedures in BS 476-4:1970 (2007).

Any material classified as class A1 in accordance with BS EN 13501-1:2002 Fire classification of construction products and building elements. Classification using data from reaction to fire tests.

ISO 1182:2020 which defines a test method for determining non-combustibility performance, under specific conditions.

As an aside, the construction industry has also had some issues with fire-proof materials in recent years. Following the Grenfell Tower Fire, a decision was taken to ban combustible materials in the cladding for buildings over 18m in height. The issue was raised again in November 2019 following a fire at The Cube in Bolton. In this case HPL cladding was used, and the building was less than 18m in height, resulting in calls for the ban on combustible cladding materials to be extended.

There are a number of other measures of materials contribution to fire, or risk of fire, which are used in general across all industries.

The heat release rate has been considered by some in the academic community to be the single most important variable in determining the fire hazard posed by different materials. It is a measure of the amount of energy lost per second (I.E. power), normalised to surface area of the material, therefore measured in kW / m2. In polymer-matrix composite materials, one of the main contributors to the HRR is from hydrocarbon volatiles being released from the burning surfaces, which migrate from the decomposing matrix into the flame where they contribute their heat of combustion via oxidation. The heat release rate at different heat fluxes can be measured with a bench-scale calorimeter, which rely on the principle of oxygen consumption, i.e., materials undergoing complete combustion release a constant amount of heat per unit mass of oxygen consumed. Despite the risks to life posed by ignitability as well as smoke and toxicity, HRR is often regarded to the best predictor of overall risk as it is a global measure of a materials contribution to combustion progress.

Another way of measuring risk of fire is by analysing smoke and toxicity of fire-released gasses. One of the most immediate dangers from combusting materials is smoke and toxic gases released from the flames, and outgassing of hazardous products from the surfaces of materials undergoing thermal breakdown. It is commonly understood that a greater risk is posed from the gaseous toxic by-products of a fire than from the flames themselves.

Smoke and toxic gasses can be quantified in cone calorimeter tests by measuring the intensity of light that is transmitted through the smoke in the exhaust duct. Alternatively, the amount of combustion products given off by a sample is related to the mass loss during the combustion process. Specimens in the test are burned above a weighing device while being subjected to an external irradiance within the range of 0 to 100 kW/m2 to measure a ‘mass loss rate’.

While these general measures give an indication of the amount of smoke is given off during certain combustion conditions, whether in volume or visual density, it does not indicate the level of risk the smoke directly presents to humans breathing it. For this to be measured, the smoke must be analysed to determine the specific chemical components and compare this to the chemicals known toxicity to humans.

Tests have been conducted specifically investigating the chemical composition of gasses released during lithium battery fires. Gas components are mainly carbon monoxide, carbon dioxide, methane, ethane, ethene, and H2. Within these emitted gases can also be traces of hydrogen fluoride, phosphine, formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, valeraldehyde, and 1,3,5-trifluorobenzene. The source for fluorine components in released gases is LiPF6 which thermally decomposes at about 90°C to lithium fluoride (LiF) and phosphor(V)-fluoride (PF5) which reacts in the presence of traces of water to HF and phosphorus oxide fluoride (POF3), both compounds are toxic.

In order to design an enclosure for fire and hazard containment for a lithium or other high power battery system a number of steps would need to be followed.

Firstly, the fire threat needs to be precisely defined. This entails the product supplier, responsible for providing the item serving as the fire source, conducting an analysis and outlining the specific nature of the fire risk.

The definition of the fire resistance of the enclosure should align with both cabin safety and structural requirements, adhering to the relevant Cabin Safety Regulations (CSs). Ensuring compliance with these regulations is crucial in determining the enclosure's suitability for the intended purpose.

From a structural perspective, especially at the aircraft level, considerations of strength and stiffness become paramount. Addressing these factors is essential in accordance with damage tolerance considerations, as outlined in AMC 20-29 Categories of damage.

A critical reference point in this assessment is the glass transition temperature, denoted as Tg. It is recommended to maintain a minimum margin of 50ºF between the Maximum Operating Temperature (MOT) and Tg for the composite material. Additionally, a 30ºF margin is advised concerning any adhesives used in the construction.

This structural evaluation primarily applies to the area surrounding the composite box. The box, when exposed to the identified fire threat, must effectively contain the fire to prevent the surrounding load-bearing structure from surpassing the Maximum Operating Temperatures (MOTs) determined by the airframe designer, influenced by factors such as material selection.

There are further considerations in the cabin safety requirements including addressing toxicity and smoke density, as mentioned earlier, to ensure the overall safety and well-being of occupants in the event of a fire.

Materials for future energy systems will require higher fire performance to meet increasing safety demands. While there is a clear advantage for safety using batteries over conventional fuels, as there is no explosive material on board, it must be borne in mind that other risks arise with the introduction of an electric power source. These new risks are less familiar to users and emergency responders. The need to withstand extreme temperature environments, not react with by-products of combustion and also maintain structural integrity to prevent further collapse or contact with other systems is a challenge for materials which are under constant scrutiny from design teams looking for lighter and cheaper alternatives.

While polymer composite materials have been the go-to source for answers to increase specific strength and damage tolerance to lighten aircraft, they fall short in applications which need to resist strong thermal, electrical or chemical attack. An increasingly popular class of materials replaces the polymer matrix with ceramic, creating a completely non-combustible material which can also maintain structural integrity even in the most extreme temperature scenarios.

The Emergence and Impact of Oxide/Oxide Ceramic Matrix Composites (CMCs)

In the realm of materials science, the quest for materials capable of withstanding extreme conditions while maintaining their integrity and performance has led to significant innovations. Among these, Oxide/Oxide Ceramic Matrix Composites (CMCs) represent a pivotal advancement, offering a blend of properties that traditional metallic materials cannot match. These composites, developed to leverage the high temperature capabilities of ceramics without their inherent brittleness, have emerged as a key solution for applications demanding durability and resistance to thermal and oxidative stress. The inception of Oxide/Oxide CMCs marked a significant leap in overcoming the limitations of conventional composites. Designed with a focus on high temperature performance, these materials combine oxide ceramic matrices with reinforcing oxide fibres, yielding composites that excel in environments where metal alloys and non-oxide ceramics can weaken. The intrinsic resistance to oxidation and thermal degradation of Oxide/Oxide CMCs has rendered them an interesting solution in sectors such as aerospace, defence, and energy—industries where materials are routinely subjected to harsh thermal environments and oxidative atmospheres.

Innovations in fibre technology, matrix compositions, and processing methods have enhanced the mechanical properties and durability of Oxide/Oxide CMCs, making them more cost-effective and environmentally sustainable than their predecessors. As we delve into the complexities and contributions of Oxide/Oxide CMCs, we uncover their transformative potential in shaping future material science and engineering, underscoring their role in advancing technological frontiers and meeting the challenges of modern engineering applications.

Historical Development and Material Properties

The historical development of CMCs, particularly Oxide/Oxide CMCs, marks a significant evolution in materials engineering, aiming to meet the demands of high temperature applications where conventional materials fall short. Initially, CMCs were developed to leverage the high-temperature capabilities of ceramics while mitigating their inherent brittleness by incorporating reinforcing fibres, thereby enhancing their toughness and durability. Oxide/Oxide CMCs emerged as a category within this broader field, designed to offer superior resistance to oxidation and thermal degradation compared to non-oxide counterparts like Silicon Carbide (SiC)/SiC composites. This intrinsic resistance to high temperature oxidation is pivotal for applications in the aerospace and energy sectors, where materials are regularly exposed to extreme thermal environments and oxidative atmospheres.

The material properties of Ox/Ox CMCs are defined by their unique composition: an oxide ceramic matrix reinforced with oxide ceramic fibres. This combination not only provides excellent thermal and oxidative stability but also maintains mechanical integrity at temperatures where metals and non-oxide ceramics would fail. The advancement in fibre technology, particularly the development of alumina-based fibres like Nextel 610 and 720, has played a crucial role in enhancing the strength and temperature capability of Ox/Ox CMCs, making them viable for more demanding applications. Moreover, the porosity of the matrix is carefully engineered to optimise the composite's mechanical properties, including its fracture toughness and resistance to thermal shock. These material characteristics are critical for the performance and reliability of Ox/Ox CMCs in service, allowing them to withstand not just high temperatures but also the mechanical stresses and environmental conditions typical of their applications.

The technological advancements in the manufacturing of Oxide/Oxide CMCs have been pivotal in addressing their historical limitations and enhancing their applicability across various high-temperature environments. Innovations have focused on refining fibre production, matrix formulations, and sintering processes. The development of high-quality oxide fibres has been crucial, with specific advancements in the spinning and heat treatment processes to achieve fibres that offer improved strength and durability at high temperature. In matrix technology, the introduction of novel slurry impregnation techniques and sol-gel processes has enabled the creation of denser, more uniform matrices that can distribute loads more effectively under multi-axial loading.

Sintering techniques have also seen significant improvements. Lower temperature sintering processes have been developed to minimise fibre damage during composite fabrication, preserving the integrity and mechanical properties of the fibres within the matrix. This progress in manufacturing technology not only makes Ox/Ox CMCs more cost-effective but also expands their potential as a sustainable alternative to other high temperature materials.

Comparing Oxide/Oxide CMCs with their Non-Oxide counterparts reveals a landscape marked by distinctive advantages and trade-offs, tailored to specific application requirements. Oxide CMCs stand out for their exceptional oxidation resistance and stability in high-temperature environments. Non-Oxide CMCs, such as those reinforced with Silicon Carbide (SiC) fibres, offer superior mechanical properties at extreme temperatures, including higher strength and stiffness. However, their susceptibility to oxidation at elevated temperatures limits their performance over time, necessitating protective coatings that add complexity and cost to their application.

The advancements in Oxide/Oxide CMCs, particularly in fibre technology and matrix compositions, have significantly bridged the performance gap between Oxide and Non-Oxide CMCs. Innovations in manufacturing processes have also played a crucial role, enhancing the mechanical properties and durability of Oxide/Oxide CMCs while maintaining their cost-effectiveness and simplifying their integration into existing systems. Oxide/Oxide CMCs present a more cost-effective solution over the long term, considering their lower maintenance requirements and longer service life in oxidative environments. This economic advantage, combined with ongoing technological advancements, positions Oxide/Oxide CMCs as a compelling alternative for a wide range of high temperature applications, challenging the dominance of Non-Oxide CMCs and traditional high-temperature metallics.

The strategic importance of Oxide/Oxide CMCs spans multiple industries, revolutionising how critical components are designed and implemented for enhanced performance and efficiency. In the aerospace sector, these materials are growing in popularity for combustor and turbine statics, where their high-temperature resistance and oxidation stability significantly improve engine efficiency and reduce maintenance requirements. Similarly, in the energy industry, their ability to withstand corrosive and high-temperature environments makes them ideal for components in power generation systems, contributing to more sustainable and efficient energy production. This cross-sectoral application underscores their transformative potential.

HTMS has played a pivotal role in the evolution and application of Oxide-based CMCs, marking a significant stride in the field of advanced materials. Their contributions have been instrumental in addressing some of the critical challenges that have historically limited the wider adoption of these composites. By pioneering innovative matrix chemistries and processing techniques, HTMS has enhanced the mechanical properties and thermal stability of Oxide/Oxide CMCs, making them more viable for high-temperature applications. One of the key advancements brought about by HTMS is the development of novel matrix materials that can be sintered at lower temperatures. This breakthrough reduces the risk of damaging the reinforcing fibres during the manufacturing process, thereby preserving the composite's integrity and performance capabilities. Such innovations not only improve the quality of the final product but also contribute to reducing production costs, making Oxide/Oxide CMCs a more attractive option for industries reliant on materials that can withstand extreme conditions.

The landscape of advanced materials engineering is witnessing a transformative phase with the maturation of Oxide/Oxide CMCs. These materials face a trifecta of challenges that delineate the current frontier of research and application. Primarily, the quest for enhanced material properties — strength, durability, and temperature resistance — remains at the forefront. This pursuit is not merely academic; it directly impacts the viability of Oxide/Oxide CMCs in extreme environments, where traditional materials succumb to the rigors of high temperatures and corrosive atmospheres. Furthermore, the scalability of manufacturing processes for Oxide/Oxide CMCs presents a significant hurdle. The specialised techniques required to produce these composites demands a level of precision and control that complicates large-scale production. Achieving cost-effectiveness, a critical factor for widespread adoption, hinges on innovating manufacturing technologies that can maintain the exquisite balance between quality and throughput. Moreover, the integration of Oxide/Oxide CMCs into existing systems and materials frameworks underscores a broader challenge of compatibility and adaptability. The development of effective joining techniques, alongside ensuring material compatibility, is essential for the seamless incorporation of these composites into complex assemblies and applications.

Concurrently, advancements in manufacturing technology are set to revolutionise the production landscape for these materials. The advent of additive manufacturing, automated fibre placement, and rapid sintering processes offers a glimpse into a future where Oxide/Oxide CMCs can be produced with unprecedented efficiency and complexity. This evolution in manufacturing is not just about scaling up; it’s about unlocking new geometries, functionalities, and applications that were previously unattainable. As we look to the future, the broader industrial adoption of Oxide/Oxide CMCs seems not just feasible but inevitable. The expanding role of these composites in aerospace, defence, green transport, energy, fire protection and potentially new sectors speaks to their strategic importance in the next wave of technological advancements. In essence, the journey of Oxide/Oxide CMCs is emblematic of the broader trajectory of materials science — a field defined by its challenges but driven by the unyielding pursuit of solutions. As these materials edge closer to realising their full potential, they underscore a commitment to not just meeting the demands of modern engineering challenges but advancing the frontiers of sustainability and efficiency in the process.

The journey of Oxide/Oxide CMCs from their inception to their current standing in the materials engineering landscape encapsulates a narrative of innovation and strategic importance across multiple industries. These composites, heralded for their unparalleled resistance to high temperatures and oxidation, have carved a niche for themselves in critical applications where traditional materials fall short. The evolution of Oxide/Oxide CMCs, underscored by significant advancements in material properties and manufacturing processes, reflects a concerted effort to address the stringent demands of high-temperature environments in aerospace, defence, and energy sectors.

The strategic adoption of these materials in gas turbines and power generation components has not only enhanced performance and efficiency but also underscored the transformative potential of Oxide/Oxide CMCs in driving advancements in material science and engineering. The role of entities like HTMS in pioneering innovations in matrix chemistries and processing techniques has been instrumental in overcoming historical limitations, marking a significant stride in the field of advanced materials. These contributions have optimised the mechanical properties and thermal stability of Oxide/Oxide CMCs, making them more viable and attractive for high-temperature applications.

However, the path forward for Oxide/Oxide CMCs is not devoid of challenges. The quest for enhanced material properties, scalability of manufacturing processes, and integration with existing systems presents hurdles that demand innovative solutions. The future of Oxide/Oxide CMCs lies in the promise of material science breakthroughs and advanced manufacturing technologies that aim to redefine performance benchmarks and expand their application scope. The potential for broader industrial adoption and the role of collaborative ecosystems in fostering innovation highlight the ongoing commitment to not just meet but exceed the demands of modern engineering challenges. This narrative underscores a broader trajectory towards sustainability and efficiency, positioning Oxide/Oxide CMCs at the forefront of materials science, ready to meet the evolving demands of the future.

The emergence of novel electric vehicles, including those in the road, rail, and air sectors, has brought about substantial demands for battery power. Ensuring the safety of occupants during thermal runaway is of utmost importance. To address this critical need, IgniShield has been developed, a cutting-edge thermal shielding solution capable of withstanding high temperatures for significantly longer durations compared to existing material options. This advancement ensures enhanced protection and peace of mind for passengers and operators alike.

Electric Vehicle thermal shielding - IgniShield

The emergence of novel electric vehicles, including those in the road, rail, and air sectors, has brought about substantial demands for battery power. Ensuring the safety of occupants during thermal runaway is of utmost importance. To address this critical need, HTMS has developed, a cutting-edge thermal shielding solution capable of withstanding high temperatures for significantly longer durations compared to existing material options. This advancement ensures enhanced protection and peace of mind for passengers and operators alike.

The use of CMCs as thermal protection shield for static batteries.

Energy storage thermal shielding

In large-scale energy storage systems, managing excessive heat is essential to maintain battery performance and safety. Drawing inspiration from advanced thermal shielding technologies used in motorsports and electric vehicles, HTMS has developed a multi-layered CMC heat shield for battery storage. Capable of withstanding extreme temperatures over prolonged periods, our multi-layered CMC solution enhances safety during thermal runaway and extends battery lifespan.  

In the realm of high-end motorsport, the demand for exceptional performance necessitates the use of low-density composite materials that can endure temperatures exceeding 700°C for extended durations. This requirement is critical to optimise the vehicle's performance to its fullest potential. To meet these rigorous standards, the ThermaLite exhaust shield was developed.

Motorsport exhaust shield - ThermaLite

Our bespoke system is a revolutionary innovation designed for Hydrogen tank casings. Conventional polymer-based casings often struggle with thermal runaway, but our cutting-edge solution offers a multi-layer and multi-functional design, providing unmatched thermal protection and impact resistance. Now, hydrogen tanks can be reliably safeguarded against extreme temperatures and potential impacts, ushering in a greener and more secure future.

Hydrogen tank thermal protection - HyperTherm

HTMS are excited to announce that we has been selected to participate in the prestigious Faraday Battery Challenge Investment Readiness Programme for 2024.

This programme, co-led by Innovate UK, Innovate UK Business Connect and Faraday Battery Challenge, supports innovative UK-based companies advancing battery technologies. It offers tailored business support, industry mentoring and access to a network of investors specifically focused on accelerating growth in the battery sector.

Being part of this initiative will HTMS strengthen our mission to speed the adoption of battery power, whilst helping decarbonise the supply chain with our cutting-edge CMC technology.


To read the full announcement and see who else is participating, click the link below.

HTMS selected for Faraday Battery Challenge Investment Readiness Programme 2024

24th July 2024 marked HTMS's first appearance at the Farnborough International Airshow, a weekly long event of immense scale and significance in the aviation and aerospace industry. Representing HTMS were CEO Danilo Di Salvo, CTO Richard Grainger, and COO Will Larkin. The sheer magnitude of the show was awe-inspiring, with four large buildings housing hundreds of aviation and aerospace businesses, all set against the backdrop of a very busy airfield, the platform for some exceptional displays of aerobatic skill from both pilots and machine . Situated close to the runway were the exclusive chalets, where the event's most significant deals were sealed—amounting to over $80 billion in contracts signed throughout the show.

HTMS was both delighted and honoured to have been invited to spend the afternoon in the Boom Supersonic chalet. This opportunity allowed Danilo, Richard, and Will to meet the Boom team in person and continue discussions on how HTMS’s CMCs could address the thermal challenges faced by their next generation supersonic airliner. We were warmly welcomed by Senior Engineer Andries Buitenhuis and SVP Scott Powell, who guided us to a scale model of Symphony, Boom's new supersonic jet engine.

HTMS discussing the use of CMCs in Boom's new Symphony engine

Here, we engaged in detailed discussions about the thermal challenges in the engine's exhaust and explored how HTMS’s unique CMCs could help the Boom team reduce weight and extend the life of their exhaust system. Later, we were treated to gin and 'supersonic' tonics on the veranda, where we watched the aircraft and helicopters in action at the show—a perfect way to conclude a busy and productive day.


The morning had been packed with meetings, both with existing clients and potential new customers. There was considerable interest in our latest developments, including complex CMC part fabrication, filament winding, and recent test results and we look forward to following up on these conversations in the coming weeks.

We were also pleased to spend time with our Advisor and Angel Investor, Luke Logan, who shared his insights on this year’s show. “It’s certainly much bigger and busier this year,” Luke observed, a sentiment we wholeheartedly agree with.


The show exceeded all our expectations, and we can’t wait to return for the next one in 2026!

Ricard, Dani, Will and Luke at Farnborough

HTMS invited to be a delegate on Innovate UK's Battery Tech GBIP to Australia in October 2024.

We are thrilled to announce that HTMS has been selected to participate in the Innovate UK Global Business Innovation Programme (GBIP) focused on battery technologies in Australia!

This prestigious programme aims to drive international collaboration and innovation in the battery sector, aligning perfectly with our mission at High Temperature Material Systems to help accelerate the journey to netzero via the use our novel CMC material to create lighter, safer and more cost effective thermal shielding for battery energy storage.



The opportunity will allow us to expand our global network, engage with leading-edge organisations and foster advancements that will benefit the entire battery energy storage & EV industries. By connecting with Australian battery producers, mining companies, oem's and research institutions, we aim to explore partnerships and collaboration opportunities that will propel our innovative thermal shielding solution to new heights.



Our COO Will Larkin will be representing HTMS alongside the delegates from Volador Energy, Auquan,  EQONIC, Minviro, Rovjok, ThinkClock Battery Labs, HalioGEN Power and Blue Dolphin Ltd all of whom we look forward to travelling and working with.



The visit will see the combined delegation visit Brisbane, Sydney, Melbourne and Perth during the first two weeks of October '24. 

Stay tuned for updates on our journey and the exciting developments ahead.

HTMS joins Innovate UK's Battery Tech delegation to Australia

We were very happy to be featured in Composites World after our successful exhibition at JEC World '24 in Paris.

CTO Richard Grainger spoke with Senior Tech Editor Ginger Gardiner about HTMS's bespoke aluminum oxide matrix CMC's being produced here in the UK.  You can read the article in full by clicking on the button below, which also covers our current range of novel CMCs.

HTMS accepted on to Type One and UKBAA's Venture into Space accelerator.

It's official.....the sky is no longer the limit for HTMS!! 🚀 👩‍🚀 🛰  

UKBAA and Type One Ventures recently launched a joint ‘Venture into Space’ programme, backed by UK Space Agency. After a rigorous judging process, we are delighted to share that High Temperature Material Systems has been chosen as one of the top 10 standout, high growth space tech businesses to take part -read the full press release here. 

“We’re looking forward to working with Type One Ventures,UK Business Angels Association,UK Space Agency and the talented team here at High Temperature Material Systems on our "Venture into Space" journey.” Will Larkin, COO at HTMS.


The other 9 exceptional businesses who we look forward to joining on the cohort are:

Alpha Earth Observation is a downstream Earth Observation company offering a dynamic, user-friendly dashboard via cloud computing for near-real-time monitoring of environmental assets such as agriculture, forestry and urban landscapes -www.alphaeo.com

Antonym is building a network of autonomous micro factories, driven by a cloud-based digital supply chain to enable local and on-demand production of precision aerospace metal parts & components closer to their point of use -www.antonym.tech

AugmentAero Combining AR Technology with AI and Machine learning for the aviation sector improving safety, efficiency and performance -www.augmentaero.com

Fluidic Logic Ltd technology enables the rapid development of manufacture ready designs for fluidic machines: from microfluidics for biotechnology, through soft robotics for wearable technologies, to hydraulic control systems for industrial robotics -www.fluidiclogic.com

Hycean Ltd is a pioneering tech company at the forefront of efficient and sustainable power solutions, innovating with their groundbreaking HYCE™ technology and Hycean-hub platform -www.hycean-ltd.com

IONETIC is a one-stop solution for battery pack technology, providing battery pack solutions that meet both performance and cost targets -www.ionetic.uk

QuInAs - ULTRARAM™ is a remarkable, patented, memory technology developed by Lancaster University. It exploits a quantum-mechanical process called resonant tunnelling, allowing ULTRARAM™ to deliver non-volatility with fast and energy-efficient write and erase, resulting in high endurance -quinas.tech

Space Power is leading the industry in LASER power beaming for space applications since 2020 – specifically supplying wireless power banks which are uniquely compatible with any spacecraft -www.space-power.com

UAP industries' flagship innovations, the Atmospheric Processing Plant (APP) and the Electromagnetic Plasma Separator (EMPS) are not just solutions to today’s environmental challenges; they’re keystones in humanity’s quest for interplanetary habitation -uapindustries.com



HTMS Accepted onto UKBAA & Type One's Venture into Space Accelerator

HTMS was delighted to exhibit our novel CMCs as part of the JEC Start-up Booster Village 2024. Our journey from Bristol to Paris began in 2023, applying among hundreds to the Start-up Booster Village competition. We received the exciting news of our successful application in February 2024, allowing just over a month to plan our logistics, marketing materials (including ‘THOSE” orange hoodies) and presentation for the event! 

At the event, our CEO Danilo Di Salvo presented HTMS’s innovative Ceramic Matrix Composite (CMC) technology to a distinguished panel, including leaders from Mercedes-Benz, Airbus, Safran, Techstars, and Owens Corning. It was an enriching experience for our team, with many attending the prestigious conference for the first time, and it was exciting to see how big the world of composites is and that it continue to grow and a farnominal rate.

This year's event was extraordinary, attracting over 40,000 visitors across three days. The Startup Booster Village buzzed with activity, showcasing twenty exceptional startups and drawing thousands of curious visitors. It was fantastic to see our booth, attract a broad range of visitors interested in how our cost-efficient CMCs could address their thermal management challenges, across Automotive, Aerospace, Energy, Space, Marine, Heavy Industry, F1 to name a few!!

The demand for an affordable CMC solution was clear, as many engineers expressed their needs matched by the capabilities of CMCs but deterred by the cost.

The social aspect of the event was equally exciting, with many stands transforming into lively bars and cocktail spots as the day concluded, offering a perfect way to unwind. And, of course, no trip to Paris would be complete without savouring the exquisite local cuisine and wine, providing our team with delightful dinners to reflect on the day’s achievements and share how far we have come in such a short space of time.

In summary, JEC was a monumental triumph for HTMS. With 100+ conversations had, with a similar number of business cards exchanged, leading to over 15 signed NDAs and several ongoing live projects across a number of sectors.

As hinted by our orange hoodies, the future looks exceptionally bright for HTMS and our CMC technology!

We are excited to announce that HTMS has been selected to take part in the NatWest Clean Transport Accelerator at the University of Warwick ⚡ 

The aim of this 6 month accelerator is to help the UK be a green leader in carbon-neutral transport for future mobility. Alongside WMG, University of Warwick they will help us bring our innovations in CMCs to the market quicker!

We can't wait to get started!

HTMS accepted onto NatWest Clean Transport Accelerator

We are delighted to announce that HTMS has been selected as a Startup Booster Finalist by JEC Group due to our innovative CMC technology.

As a result, we will have our own stand at the JEC conference at the beginning of March, we will pitch our materials to world class businesses such as Airbus, Mercedes-Benz AG and Safran, and we will have our own booth for conversations with prospective customers and partners.

Company CEO, Danilo commented: "We are thrilled to have been selected as finalists considering the incredible competition and innovation that is in the composite market at the moment. We are feeling a strong pull-through for CMC material, that is once again reflected in this announcement."

Hopefully, we will see you in Paris 5th to the 7th of March!

Read the full press release here: Composites Startup Booster Finalists 2024  

We're delighted to announce that we have moved in to our new facility!We have moved the HTMS team in to a customised facility in Bristol, just a few minutes up the road from our good friends at the National Composites Centre. This marks an exciting and significant step for us as a business.

HTMS Move to a New Facility in Bristol

We're delighted to announce that we have moved in to our new facility!

We have moved the HTMS team in to a customised facility in Bristol, just a few minutes up the road from our good friends at the National Composites Centre. This marks an exciting and significant step for us as a business.

Co-founder, Danilo Di Salvo commented:
"I'm proud of the whole team - this has been a massive job for us. We needed to find a facility that ticked many boxes and we have located the perfect place for us to scale our CMC products at pace. This new facility will allow us to control our manufacturing environment whilst significantly increasing our R&D pace. I'm absolutely delighted."

Co-founder, Richard Grainger remarked:
"Safety and our environment have always been paramount for us at HTMS. Our new lab ensures that we can work in a safer environment and gives us the space to grow through equipment purchases and increasing our staffing levels. The team have done a thorough and fantastic job."


UK-based advanced materials company High Temperature Material Systems (HTMS) has successfully closed its £300,000 pre-seed funding round. The round was led by SFC Capital, with participation from BBI Investments and a leading UK based angel investor. The funding will be used to accelerate go-to-market and expand the product into a number of other industries.

HTMS Funding Announcement

UK-based advanced materials company High Temperature Material Systems (HTMS) has successfully closed its £300,000 pre-seed funding round. The round was led by SFC Capital, with participation from BBI Investments and a leading UK based angel investor. The funding will be used to accelerate go-to-market and expand the product into a number of other industries. 

HTMS was established in 2021 by two of the UK’s leading composite engineers, DrDanilo Di Salvo and Dr Richard Grainger. The company specialises in producing ceramic matrix composites (CMC) that have historically been used in the aerospace and defence industries, and are now expanding their use case to a number of novel industries including space, nuclear, automotive and energy. CMCs, which were previously underutilised in the UK market, are now generating interest within the advanced materials business as high temperature operation requirements become more apparent. HTMS has created new, low-cost, multi-functional oxide-based CMC materials that allow systems to run at substantially higher efficiency.

HTMS was backed in 2022 by MBDA, one of Europe’s largest defence companies, through winning the Ceramic Matrix Composite Airframe Technology Challenge competition. As a result, HTMS has steadily been building its technology capability as well as commercial partners, which now include the UK’s National Composites Centre. The company has also recently partnered with the UK Atomic Energy Authorityopening up the realms of oxide-based CMCs.

The company is also recently joined by Luke Logan FREng, who worked with Rolls-Royce for over 20 years and was the chief engineer behind the Airbus A380 engine (Trent 900). The company has now developed a strong team to develop its capabilities for the coming years ahead. 

Danilo Di Salvo, CEO at HTMS, commented “We are delighted to have SFC Capital invest in the business and we look forward to working and learning together with one of the UK’s largest investors. HTMS is at the forefront of advanced materials development and we are excited to expand into a wider range of industries over the coming months”.

Adam Beveridge, Investment Associate at SFC Capital added “HTMS are leading the way in the UK in advanced materials development, proven by their previous work with MBDA. Building on its deep tech abilities, we are looking forward to seeing their development within and outside the UK very soon”.


November 2022 marked the end of our very first project.We presented our work to a panel at MBDA in Stevenage highlighting one of our novel high temperature multifunctional Ceramic Matrix Composite systems. We are very proud to have received excellent feedback and we look forward to enhancing our relationship with MBDA further in 2023.

HTMS Complete First Customer Project

November 2022 marked the end of our very first project.

We presented our work to a panel at MBDA in Stevenage highlighting one of our novel high temperature multifunctional Ceramic Matrix Composite systems. We are very proud to have received excellent feedback and we look forward to enhancing our relationship with MBDA further in 2023.

We are grateful to MBDA and the National Composites Centre for creating such an exciting project that has allowed us to launch in to this sector. As we continue to explore the capability of our material systems, we find more and more possibilities in diverse areas.


Thought leadership articles on the world of Ceramic Matrix Composites and the role they play in the world.

Welcome to HTMS Insights

Fibres for Oxide-based Ceramic Matrix Composites

Fire-Resistant Materials for Lithium Battery Enclosure

The Emergence and Impact of Oxide/Oxide Ceramic Matrix Composites (CMCs)

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