Integrated 3D CMC-C/C Composites for Hypersonic Leading Edges

Hypersonics programs require durable, lightweight, cost-effective hot structures that can be manufactured in large sizes. Fiber-reinforced ceramic matrix composites (CMC) with enhanced interlaminar and through-thickness mechanical properties for operation at 1500-3000C are potential enablers for hypersonic vehicles. In previous work, Ultramet demonstrated the fabrication of carbon fiber-reinforced refractory carbide CMCs for missile and railgun projectile nosetip and aeroshell applications using a rapid melt infiltration process. These CMCs have undergone extensive testing under laser and arcjet heating and exhibited no erosion at nearly 2900C. They have also exhibited high toughness and thermal shock resistance. Ultramet has also demonstrated the fabrication of two-dimensional fiber-reinforced CMC-lined carbon/carbon (C/C) components, combining the benefits of the CMC with the reduced weight and cost of C/C. Such structures were produced as aeroshells with insulating aerogel-filled structural foam cores. In this project, to produce structures with enhanced properties for operation at 1500-3000C, Ultramet will combine modified melt infiltrated CMC-C/C processing with three-dimensional fiber reinforcement to optimize interlaminar and through-thickness properties while maintaining acceptable in-plane properties. Base effort development will focus on mechanical properties, both as-fabricated and following high temperature exposure. The option task will assess performance in a laboratory-scale thermal environment.