High strength and high work hardening rate in oxygen gradient Ti-15Mo alloy  

作　　者：Zhixin Wang Kai Yao Binkai Du Suyun He Xiaohua Min Shewei Xin Shijian Zheng 

机构地区：[1]Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology,School of Materials Science and Engineering,Hebei University of Technology,Tianjin 300130,China [2]School of Materials Science and Engineering,Dalian University of Technology,Dalian 116024,China [3]Northwest Institute for Non-Ferrous Metal Research,Xi'an 710016,China

出　　处：《Journal of Materials Science & Technology》2024年第31期56-62,共7页材料科学技术(英文版)

基　　金：financially supported by the National Natural Science Foundation of China(No.52301144);the Hebei Province High Education Science and Technology Research Project(No.QN2023101);the Natural Science Foundation of Hebei Province(No.E2023202124);the Central Guidance on Local Science and Technology Development Fund of Hebei Province(No.226Z1012G).

摘　　要：The low work hardening is a prominent deficiency for high-strength titanium(Ti)alloys.The gradient design of oxygen content was adopted to realize the coupling deformation of{332}<113>twinning and dislocation slip in the Ti-15Mo alloy.This oxygen gradient alloy exhibited an optimal balance of yield/tensile strength(700 and 848 MPa)and elongation(25%),with remarkable work hardening behavior.The dominated dislocation slip deformation and the solution strengthening of oxygen atoms in the oxygen-rich region resulted in a remarkable increase in yield strength.The successive formation of{332}<113>twins and piled-up geometrically necessary dislocations around the twin boundaries in the oxygen-free region induced remarkable back stress strengthening,maintaining the high work hardening rate,which resulted in a stable increase in strength.The twins and dislocations formed at the crack tips effectively hindered the cracking behavior,avoiding premature necking.The present study provides a novel idea for designing oxygen layer-distributed Ti alloys,which further improves the strength-ductility tradeoff.

关 键 词：Titanium alloys Oxygen gradient Work hardening Heterogeneous material DUCTILITY 

分 类 号：TG1[金属学及工艺—金属学]