Today’s aerospace industry is moving towards reusable launch vehicles and innovative technologies to optimize production and promote sustainability in space. This drive includes advanced approaches such as assisted retro propulsion and sustainable composite design, reflecting a more efficient and innovative future for space.
Amorim Group: origin and evolution
Rooted in the cork industry since 1870, the Amorim Group has become the world leader in cork materials. Focused on sustainable growth, the Group has diversified its activities, vertically integrating the cork business in the 1960s with the creation of Amorim Cork Composites. Maintaining its family character, the Amorim Group has a consolidated position in various sectors on five continents.
Amorim Group, is renowned for innovation and sustainability. With significant investment in research, it offers a portfolio of high-quality products, focusing on performance and contributing to the conservation of cork oak forests. As a model of a sustainable economy, Amorim Group achieves a harmonious balance between economic success, social responsibility, and environmental protection.
Cork: an exceptional raw material
Cork is the outer bark of the cork oak tree (Quercus Suber), a completely natural plant tissue that wraps around the trunk and branches of the tree. Its honeycomb structure is made up of microscopic cells filled with an air-like gas and coated mainly with suberin and lignin, with up to 40 million cells in one cubic centimetre of cork. Often referred to as “nature’s foam” due to its honeycomb cell structure, cork has a closed cell configuration that makes it:
- lightweight
- Impermeable to liquids and gases
- Resistant to friction
- Vibration isolator
- Thermal and acoustic Insulator
Cork is sustainably harvested by specialised professionals without damaging the trunk, allowing the tree to produce a new layer of outer bark for future harvesting. During the long average life of a cork oak, which is around 200 years, cork can be harvested around 17 times. This characteristic makes cork not only a natural raw material, but also a renewable and recyclable resource that has played a crucial role in the history of launch vehicles, especially in the early years of space exploration, due to its low thermal conductivity and its ablative and insulations properties.
Why cork is important for thermal insulation on space missions
Thermal Protection Systems (TPS) insulation materials play a critical role in the successful launch and operation of manned and unmanned spacecraft. During launch and return to the Earth’s atmosphere, the structure of the rocket or spacecraft is exposed to extreme temperatures that can lead to carbonisation. Thanks to a unique cork compound, TPS materials lead the way in providing thermal protection shields that have successfully withstood many decades of space travel. Amorim Cork Composite’s high-quality solutions for the aerospace industry position them as ideal thermal protection materials with excellent ablation and insulation properties.
Cork-based ablative materials work by absorbing large amounts of heat through a phase change. During the phase change, a char layer is formed which acts as an insulator, protecting the inner material and slowing down the thermal degradation of the shield while maintaining its geometry.
Besides being an ablative material with remarkable thermal protection performance, it is generally less expensive than other materials used in the aerospace market, easy to handle and, as a natural material, the sustainability of cork TPS materials remains high, while available with short lead times.
Amorim Cork Composites in spacecraft – Case Studies
Amorim Cork Composites has been a global supplier to the aerospace industry, offering sheet or molded materials and specially graded cork granules. The use of cork in spacecraft and rockets dates back to the Apollo XI mission, marking the beginning of its integration in various programmes such as Titan, Delta, Mars Rover and Atlantis.
- In the 1960s and 1970s, cork was used extensively in the command modules of space capsules, particularly in the Apollo programme. It formed part of a thermal insulation system, along with materials such as polyurethane foam and Kapton, to protect astronauts from extreme temperatures during atmospheric re-entry.
- In 2012, Amorim Cork Composites’ technical products played a crucial role in the launch of the European Space Agency’s (ESA) Vega rocket. The rocket, designed for payloads between 300 and 1500 kilometers, utilized cork composite Thermal Protection Systems (TPS) to prevent overheating during launch. Cork’s natural attributes, including thermal and vibrational insulation and fire resistance, were key factors contributing to the mission’s success.
Amorim Cork Composites in European Funded Projects
RETALT
Starting in 2019, Amorim Cork Composites was part of an European Consortium within the project RETALT, which had as main objective to investigate launch system re-usability technology of VTVL vehicles.
For Amorim Cork Composites, the main goal was the development of a new TPS, possible of being applied in-situ, in complex shapes/geometries, for the base plate of the vehicle.
TPS05, the name for the new trowelable TPS (currently at TRL 4), was composed by a resin matrix, filled with cork granules, that ensured the thermal insulation during ablation, keeping the structure and reducing the recession during L2K plasma tests, when compared with typical cork ablative TPS.
SALTO
Since 2023, Amorim Cork Composites has been integrating HORIZON EUROPE project SALTO Consortium, leaded by Ariane Group, where a new concept of TPS has been developed. The continuous need of increasing the sustainability and the reusability of launchers, led the company to develop a 100% bio-content TPS material, which is composed by cork granules agglomerated with a bio-resin. In addition to that, in direct partnership with iD-Services, the new TPS will be applied in replaceable tiles, which will allow to easily substitute the damaged TPS after each mission.
Author of the article Lorenzo Iacopino
Lorenzo Iacopino is currently pursuing his Master’s degree in Aerospace Engineering at the esteemed University of Bologna. His academic pursuits are driven by an unwavering passion for spacecraft and astronomy, fueling his commitment to exploring the vast frontiers of these disciplines. Beyond his scholarly endeavors, Lorenzo finds great satisfaction in contributing to the advancement and popularization of scientific knowledge. He is eager to learn from the space sector leaders and share his insights and expertise fellow scholars and the broader audience.