Coaxial Test Fixture and Pulsed Power Supply for Contact Material Screening Testsa

Abstract

A coaxial test fixture and a pulsed power supply have been built to conduct high-current screening tests on candidate materials for contacts to be used in first wall connectors on fusion devices, particularly tokamaks. The fixture was operated with half-sine-wave pulses of less than or equal to 300 kA; it is designed for carrying currents of up to 600 kA for approximately 300 ms at a repetition rate of 1 pulse every 5 minutes. The fixture is built as a vacuum vessel and capable of testing specimens in an ambient temperature of 300/sup 0/C. Instrumentation is provided to measure the current pulse, contact voltage drop, contact pressure, the strain caused by contact pressure, and the operating temperature. The test fixture, its power supply and possible future upgrades are described.