Superplasticity and Characterization of TIMETAL~®54M Sheets

摘要

TMETAL~®54M (Ti-5Al-4V-0.75Mo-0.5Fe) or Ti-54M is an alpha/beta titanium alloy developed by TMET. Earlier technical publications have confirmed that laboratory scale Ti-54M sheets exhibit superior SPF capabilities compared to Ti-6Al-4V (Ti-64), in terms of flow stress, temperature and strain rate. Various gauges of these sheets, ranging from 0.64mm to 4.57mm, were produced on a production scale using TMET patented process. Coupon tests were performed in accordance to ASTM E2448 and the results confirmed that the SPF capability of these sheets at a temperature as low as 774℃, which is a significant cost benefit in the SPF fabrications. The present paper discussed basic properties of Ti-54M sheets along with SPF coupon tests results showing lower temperature superplasticity. The low temperature superplasticity of Ti-54M is due to the combined effect of alloying elements and finer primary alpha particle size.