Deformation behaviors of as-built and hot isostatically pressed Ti-6Al-4V alloys fabricated via electron beam rapid manufacturing

摘要

The deformation behavior of as-built and hot isostatically pressed(HIP)Ti-6Al-4V alloys fabricated using electron beam rapid manufacturing(EBRM)were investigated in this work.The deformation characteristics were characterized using a laser scanning confocal microscope and electron back-scattered diffraction(EBSD).In the as-built sample,prismatic slip was the main mode of deformation,as well as a small amount of basal slip and cross-slip.Some planar slip lines with large length scales were observed across severalαlamellae.After hot isostatical pressing,prismatic and basal slip were the main mode of deformation,accompanied by abundant cross-slip and multiple slip,and most of the slip lines were blocked within an a lamellae.These differences in deformation behavior were associated with the coarsening of a laths and the more retained p phase after HIP compared to the as-built alloy.More cross-slip and multiple slip can lead to superior elongation-to-failure and a greater strain hardening effect in the HIP alloy compared to the as-built sample.