Mechanical Fire Resistance of Aeronautical Composites

In the aeronautical industry, numerous studies show that around 50% of fatalities are due to fire situations. . The development of larger aircraft, incorporating new sources of propulsion (electric or H ₂ ), and lighter (with increased use of carbon-fiber-reinforced polymer matrix composite parts) raises several questions concerning on-board safety, particularly in terms of the behavior of materials and structures exposed to fire, depending on the nature of the flame (kerosene or hydrogen). Reducing this risk further involves developing structural materials that are increasingly resistant to fire. Organic matrix composites (OMCs) give structures excellent resistance to flame penetration in the event of fire, but at the cost of highly complex thermal, chemical and mechanical behavior. The – standards relating to the fire resistance of – materials imposed by certification authorities are among the most stringent. It is therefore essential to understand/predict the reaction to fire of composite materials, and ultimately of structures and assemblies.

To date, relatively few studies have investigated the influence of thermal aggression (temperature, heat flux, flame) on the structural properties of CMOs combining fibrous reinforcement (carbon, glass, aramid, etc.) and polymer matrix. . The main types of fire-induced damage within laminates have been identified: formation of a carbonaceous zone (char), softening and degradation of constituents (matrix and fibers), delamination and matrix cracking. Efforts to characterize the fire behavior of CMOs focus mainly on their ability to withstand mechanical loading at high temperatures, depending on the nature of the polymer...