Influence of cold rolling ratio on the development of <001>β recrystallization texture component in a β-type Ti-Nb-Sn biomedical titanium alloy

초록

beta-type titanium alloys exhibit anisotropy of elastic modulus and the (001)(beta)//rolling direction (RD) texture greatly contributes to reducing the elastic modulus. This study investigates the influence of cold rolling (CR) reduction ratio (70%, 80%, 85%, and 95%) on the development of <001>(beta)//RD recrystallization texture in a beta-type Ti-15Nb-5.5Sn (at.%) biomedical titanium alloy. All solution-treated specimens exhibited a single beta phase at room temperature. EBSD inverse pole figure maps showed that as the CR ratio increased, the beta grains progressively transformed from a weak orientation to a dominant <001>(beta)//RD texture. The texture intensity increased sharply at CR ratios >85%, while grain size varied only slightly (34-46 & micro;m). These results demonstrate that a CR reduction ratio of higher than 85% is beneficial to develop a strong <001>beta//RD recrystallization texture. This work provides a processing route to tailor crystallographic texture for reducing elastic modulus in beta-type Ti-Nb-Sn alloys for biomedical applications.

키워드