Redesigning a Reaction Control Thruster for Metal-Based Additive Manufacturing: A Case Study in Design for Additive Manufacturing

Abstract

Prior research has shown that powder bed fusion additive manufacturing (AM) can be used to make functional, end-use components from powdered metallic alloys, such as Inconel® 718 super alloy. However, these end-use products are often based on designs developed for more traditional subtractive manufacturing processes without taking advantage of the unique design freedoms afforded by AM. In this paper, we present a case study involving the redesign of NASA’s existing “Pencil” thruster used for spacecraft attitude control. The initial “Pencil” thruster was designed for, and manufactured using, traditional subtractive methods. The main focus in this paper is to (a) review the Design for Additive Manufacturing (DfAM) concepts and considerations used in redesigning the thruster and (b) compare it with a parallel development effort redesigning the original thruster to be manufactured more effectively using subtractive processes. The results from this study show how developing end-use AM components using DfAM guidelines can significantly reduce manufacturing time and costs while introducing new and novel design geometries.