Boron Carbide Matrix Composites for Aircraft Friction Materials

Next generation aircraft braking materials need to improve the minimum dynamic friction coefficient and volumetric heat capacity as compared with state-of-the-art carbon/carbon braking materials. These improvements will allow more compact, lighter weightbraking systems to be developed for future aircraft. Additionally greater wear resistance is required to reduce the life cycle costs of the brake material. Ceramic matrix composites potentially address these needs. In particular a carbon fiberreinforced boron carbide matrix composite has been demonstrated to possess desirable thermal, mechanical and tribological behavior.The Phase I program fabricated carbon fiber reinforced boron carbide composites via chemical vapor infiltration (CVI). The resulting ceramic matrix composite exceeded the preliminary estimates of volumetric heat capacity as well as meeting targetedobjectives for other thermal and mechanical properties. The Phase II program will optimize the fabrication process of these materials as well as produce and test a full-scale military brake replacement. The resulting material properties and test resultswill be critically examined in collaboration with an industry consortium of brake system manufacturers.