| Abstract Scope |
Metastable beta titanium alloys offer attractive properties given their ability to form refined microstructures. However, allotriomorphic alpha at the grain boundaries often limits the ductility in these alloys. A beta anneal slow cool age (BASCA) heat treatment is often used with Ti-5553. Ti-5Al-2Sn-2Zr-4Cr-4Mo (Ti-17) is also an excellent material to undergo a BASCA heat treatment as it is beta rich and has a relatively low beta transus. In this study, Ti-17 underwent a variety of different whole and partial BASCA heat treatments, mainly resulting in basketweave microstructures. The grain size, as well as the ratio of grain boundaries with and without allotriomorphic alpha, were evaluated with different heat treatment parameters, and it was found that higher cooling rates resulted in less alpha lathes on the grain boundaries. Scanning electron microscopy (SEM) in conjunction with back scattered electron (BSE) imaging was used to study the material after heat treatment. |