Evaluation of TaC-Based Materials and Nozzle Concepts for Aluminized Solid Rocket Motors

Fielding of advanced missile defense interceptors is strongly dependent upon innovative concepts and technologies that can be applied across the Ballistic Missile Defense System to stay ahead of the threat, improve system capabilities and effectiveness, and lower life cycle costs. Tantalum carbide (TaC) based materials are being developed for potential employment as nozzle liners in axial thrust motors due to their ultra-high temperature capabilities. Plasma Processes, Inc. has optimized vacuum plasma spray (VPS) techniques to fabricate dense TaC based components. Although, property and microstructural studies of VPS Ta4HfC5 and Ta55C45 appear very promising, basic relationships between microstructure, processing and mechanical behavior are still poorly understood. In order to elucidate these basic relationships and offer insights for tunable microstructure deformation property control, additional detailed analytical microscopy studies are warranted. Previous manufacturing efforts have demonstrated the survivability of subscale nozzles consisting of a thin VPS TaC-based liner with a VPS rhenium (Re) support jacket. Alternatives to Re, such as Ta10W, are needed to reduce costs, however further studies are needed to increase the manufacturing readiness level of VPS Ta10W. Although significant progress has been achieved, continued studies are imperative to the progression of VPS Ta4HfC5 and Ta55C45 chemistries and nozzle designs for current and future missile defense interceptors.