Advanced Fabrication Techniques for High Precision Rotors

An advanced fabrication technique is proposed to improve producibility, performance, and reliability of low vibration turbo-Brayton cryocoolers. The fabrication process will improve dimensional control in sub-miniature, high-speed precision rotors,allowing for further reductions in size without compromising the basic advantages of the turbo-Brayton cooler. During Phase I test rotors will be fabricated, inspected, and tested to establish the important parameters of the process and the feasibility ofthe approach. In Phase II the process will be used in fabricating a sub-miniature cryogenic turboalternator. The machine will be tested to verify the performance and reliability gains. The successful completion of this project will result in improvedcryocooler performance, higher reliability, reduced system mass, and reduced development costs for these devices. Implementation of this process will improve the producibility, reliability, and durability of reverse-Brayton cryocoolers. It will alsoresult in the necessary tools for extending the application of turbo-Brayton coolers to a broader range of temperatures and cooling loads. The primary applications include those where long life, high reliability, low power, and low mass are critical, suchas providing cryogenic cooling to space-based sensors and instruments.