High pressure hydrogen effect on creep-rupture properties of superalloys

摘要: The automotive Stirling engine, being developed by the United States Department of Energy and NASA, uses highpressure hydrogen as working fluid. longterm effects at high temperature on properties alloys are relatively unknown. most critical component in engine is heater head, which consists cylinders, tubings, regenerator housing. Candidate for these parts must meet property requirements be low cost application. Wrought tubing cast cylinders housings were tested air 15 MPa 650° to 925 °C. This paper evaluates results wrought alloy 19-9DL CRM-6D. Six specimens evaluated creeprupture simultaneously H2 under constant initial stress conditions, creep extensions monitored with transducers placed internally. Air data analyzed using Orowan-Sherby-Dorn relationship. In both CRM-6D, did not significantly affect level 3500- hour rupture life, design limits 28 870 °C tube 119 775 CRM-6D housing met. However, had a deleterious effect ductility alloys, development way.