Flow Stress Determination for Metals at Forging Rates and Temperatures

Abstract

In this study, the uniform compression test is used to determine the flow stress of 403 stainless steel, Waspaloy, Ti-6Al-2Sn-4Zr-2Mo, Inconel 718, Ti-8Mo-8V-2Fe-3Al, and, AISI 4340 at various forging temperatures. The ring-compression test is used to determine the flow stress of 6061 aluminum, Ti-7Al-4Mo, 403 stainless steel, Waspaloy, 17-7 PH stainless steel, Ti-6Al-4V, Inconel 718, Ti-8Al-1Mo-V, 7075 aluminum, and Udimet 700 alloy at forging temperatures. All the tests were conducted, at practical deformation rates encountered in forging, on an instrumented high-speed forging press. For the same material and at similar temperature and deformation-rate conditions, the data obtained from the uniform-compression and ring-compression tests were compared. It was found that the results obtained with rings 3-in. O.D., 1.5-in. ID and 1 in. high were practically identical to those obtained from the isothermal uniform-compression tests conducted with samples 1-in. dia and 1.5 in. high.