Effect of annealing temperature on microstructure and mechanical properties of cold-rolled commercially pure titanium sheets  

退火温度对冷轧商业纯钛板材组织和力学性能的影响

作　　者：Shuai ZHAO Yang WANG Lin PENG Yuan-xiang ZHANG Rong RAN Guo YUAN 赵帅;王洋;彭琳;张元祥;冉蓉;袁国(东北大学轧制技术及连轧自动化国家重点实验室,沈阳110819;攀钢集团研究院有限公司,攀枝花617067)

机构地区：[1]State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110819,China [2]Pangang Group Research Institute Company Limited,Panzhihua 617067,China

出　　处：《Transactions of Nonferrous Metals Society of China》2022年第8期2587-2597,共11页中国有色金属学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China (No.52104372);the Fundamental Research Funds for the Central Universities,China (No.N2107001);the China Postdoctoral Science Foundation (No.2019M651129)。

摘　　要：The strength of traditional commercially pure titanium(CP-Ti) alloys often fails to meet the demand of structural materials. In order to enhance their mechanical properties, the cold-rolled CP-Ti alloys were annealed at different temperatures, and the recrystallization behavior and texture evolution were investigated. It was found that the bimodal microstructure(equiaxed and elongated grains) was formed after partial recrystallization, and the corresponding sample exhibited an excellent combination of ultimate tensile strength(702 MPa) and total elongation(36.4%). The recrystallization nucleation of CP-Ti sheets occurred preferentially in the high strain and the high-angle grain boundaries(HAGBs) regions. Meanwhile, the internal misorientations of the deformed heterogeneous grains increased and transformed into HAGBs, which further promoted the recrystallization nucleation. The main recrystallization texture was basal TD-split texture transformed from cold-rolled basal RD-split texture, and the oriented nucleation played a dominated role during recrystallization.传统的商业纯钛(CP-Ti)合金强度往往不能满足结构材料的需求。为了提高其力学性能,对冷轧CP-Ti合金在不同温度下退火,并详细研究其再结晶行为和织构演变。结果表明,部分再结晶形成的双态结构(等轴和拉长的晶粒)表现出极限抗拉强度(702MPa)和总伸长率(36.4%)的优异结合。CP-Ti板材的再结晶形核优先发生在高应变和大角度晶界区域。同时,变形不均匀晶粒的内部取向差增大并转变成大角度晶界,进一步促进再结晶形核。主要再结晶织构是由冷轧基面RD-分裂织构转变而来的基面TD-分裂织构,再结晶过程中定向形核起主导作用。

关 键 词：commercially pure titanium recrystallization nucleation bimodal microstructure mechanical properties TEXTURE 

分 类 号：TG156.2[金属学及工艺—热处理] TG146.23[金属学及工艺—金属学]