Ductility and High Cycle Fatigue Behavior of Boron-Modified Orthorhombic Titanium Alloys

摘要：

The grain sizes of two kinds of orthorhombic alloys, namely (O+B2)-type Ti-22Al-llNb-2Mo-lFe and (O+α2)-type Ti-27. 5Al-13Nb, were successfully reduced by the minor addition of boron (B) (less than 0. 1 weight ％). For example, the grain size in the B2 solution-treated condition was reduced from 1 mm for B-free alloys to 80 μm by the addition of 0. 1％ B,and accordingly, the colony size within the grains was greatly reduced. The tensile elongation at room temperature and higher, and the room temperature high cycle fatigue (HCF) strength of these two B-modified alloys increased remarkably compared to the B-free alloys. Careful SEM observation revealed that the fatigue crack initiated neither from the TiB/matrix interface nor from the TiB itself but rather from the shear fracture across the colony. Therefore,the reduced colony size, which corresponds to the shorter slip length, was thought to be responsible for the significantly higher HCF strength exhibited by the B-modified alloys.

关键词： Orthorhombic titanium alloy boron addition colony refinement tensile elongation high cycle fatigue fatigue crack initiation

作者: M. Hagiwara T. Kitaura Y. Ono T. Yuri T. Ogata

作者单位: Kyushu Institute of Technology, 2-4 Hibikino, Wakamatsu-ku ,Kitakyushu 808-0196, Japan National Institute for Materials Science, 1-2-1 Sengen, Tsukuba,Ibaraki 305-0047, Japan

会议类型: 国际会议

会议名称: The 12th World Conference Titanium(第十二届世界钛会 Ti-2011)

会议地点: 北京

会议语种:英文

页码: 892-895

在线出版日期: 2011-06-19（万方平台首次上网日期，不代表论文的发表时间）