Precipitation Behavior and Microstructural Evolution of α Phase during Hot Deformation in a Novel β-Air-Cooled Metastable β-Type Ti-B12 Alloy

Metals

Jinyong Zhang¹  Zhaoxin Du²  Fuyu Dong³  Jun Cheng⁴  Sen Yu⁴  Xiaoyong Zhang⁵  Jinyang Gai⁵  Jinshan Li⁶ 

[1] School of Material Science and Engineering, China University of Mining and Technology, Xuzhou 221008, China;School of Materials Science and Engineering, Inner Mongolia University of Technology, Hohhot 010051, China;School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, China;Shaanxi Key Laboratory of Biomedical Metal Materials, Northwest Institute for Nonferrous Metal Research, Xi’an 710016, China;State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China;

关键词: metastable β-type Ti alloy;    isothermal compression;    precipitation behavior;    variant selection;    thermal-mechanical asymmetric coupling;   

DOI  :  10.3390/met12050770

来源: DOAJ

【 摘 要 】

The precipitation behavior and microstructural evolution of α phase in a novel metastable β-type Ti alloy, Ti-10Mo-6Zr-4Sn-3Nb (wt.%), during isothermal compression are investigated in this study through the use of SEM (scanning electron microscope), TEM (transmission electron microscope) (HRTEM) (high-resolution transmission electron microscopy) and EBSD techniques. The results show that some finer α precipitates are randomly distributed within the β matrix during hot deformation. The morphological characteristics of α precipitates are distinctly different from those of α precipitates during the same solution-plus-aging treatment. The volume fraction of α precipitate gradually increases with increased true strain. A large proportion of precipitated α phases are prone to be precipitated at HAGBs (high-angle grain boundaries) and LAGBs (low-angle grain boundaries) during isothermal deformation. On the contrary, only a small amount of spherical α phases is precipitated within the β grain. The crystallographic orientation relationships for most spherical α precipitates formed at LAGBs and within the β grains are similar, whereas the crystallographic orientation relationships for α precipitates at grain boundaries are significantly different. The precipitation behavior of α phase in the Ti-B12 alloy during hot compression is considerably influenced by the density of dislocations.

【 授权许可】

Unknown