Thermal Spray Forming of Refractory Sample Ampoule Carbridges for Single Crystal Growth Space Furances

摘要

A thermal spray proces is being used to build up refractory metals and ceramics into a containment cartridge for high temperature, single crystal semi-conductor growth experiments. This process uses high energy plasma inside a low pressure (100-200 torr) inert environment to apply layers of material onto a removable mandrel. A variety of materials are being characterized and evaluated against a demanding set of requirements, including high service temperature (1700 deg C), oxidation resistance, and resistance to liquid metal attack. Techniques to spray form refractory metals (tungsten, molybdenum, niobium, tantalum) and ceramics (alumina, boron nitride) are being developed in the Plasma Spray Cell at Marshall Space Flight Center.