Low Cost, Lightweight Pintle Design for Divert and Attitude Control Systems

Current missile divert and attitude control system designs employ pintles in the nozzle throat to achieve controlled thrust propulsion. The pintle materials must be able to withstand high gas temperatures (>3000 ¿F) and severe thermal/mechanical shockenvironments without excessive erosion. Current divert valve pintles are machined from solid rhenium, which is extremely heavy and very expensive to produce. In order to reduce weight, cost and lead time while maintaining thermal and structuralperformance, an improved design and manufacturing approach is proposed herein to replace the current machined solid rhenium pintle with a thin wall rhenium outer shell electrodeposited over a lower cost, lightweight core material. The primary focus of thePhase I research will be on the design and analysis of a light weight pintle and preliminary demonstration of an Electroforming process to produce multiple pintle components. Design trade studies will be performed to establish the rhenium coating thicknessand to evaluate different graphite and carbon/carbon core materials and geometries using finite-element analyses. A final demonstration component design will be developed and produced for future hot-gas testing in Phase II. The proposed Phase I programwill directly support research and development and production programs for controlled thrust solid rocket motor and missile divert and attitude control system applications. The most immediate commercial application of the proposed technology is forcommercial spacecraft attitude control systems