Effects of stress state on texture and microstructure in cold drawing-bulging of CP-Ti sheet  

纯钛板拉胀成形中应力状态对织构和微观组织的影响(英文)

作　　者：李宏伟[1] 张下陆[1] 陈甲元[1] 李金山[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室,西安710072

出　　处：《Transactions of Nonferrous Metals Society of China》2013年第1期23-31,共9页中国有色金属学报（英文版）

基　　金：Project(2010CB731701) supported by the National Basic Research Program of China;Projects(50805121,51175428) supported by the National Natural Science Foundation of China;Project(50935007) supported by the National Natural Science Foundation of China for Key Program;Project(NPU-FFR-JC20100229) supported by the Foundation for Fundamental Research of Northwestern Polytechnical University in China;Project(2011-P06) supported by the Foundation of the State Key Laboratory of Materials Processing and Die & Mould Technology,Huazhong University of Science and Technology;Project(B08040) supported by Program of Introducing Talents of Discipline to Universities("111"),China

摘　　要：Three different stress states of the combination of tensile（t） stress and compressive（c） stress,t t,t c and t c c,exist in the deformed commercially pure titanium（CP-Ti） sheet during cold drawing-bulging.The textures and microstructures in the different stress state regions were investigated by means of XRD and TEM analysis.Similar development of texture and microstructure is achieved with less thickness strain under multiaxial stresses in drawing-bulging than in cold rolling.The results show that texture and microstructure are much sensitive to multiaxial stresses.Twinning is more easily activated under compressive stress than tensile stress.Prism a slip is heavily affected by tensile stress,resulting in a remarkable change of the intensity of（0°,35°,0°） texture,while pyramidal c＋a slip,forming（20°,35°,30°） texture,weakens with the increase of thickness strain in spite of stress state.纯钛板拉胀成形中不同部位存在3种不同的应力状态:拉拉、拉压、拉压压。分别在这3种应力状态部位取样,采用XRD和TEM方法研究这些样品的织构和微观组织。结果表明,在纯钛板冷轧过程中需要较大应变量才出现的织构和微观组织在纯钛板拉胀成形的很小厚向应变下就出现了,表明织构和微观组织对多向应力状态十分敏感;孪晶在压应力状态下比在拉应力状态下更容易激活;拉应力对棱柱型a滑移影响显著,导致(0°,35°,0°)织构强度明显变化;而形成(20°,35°,30°)织构的锥型c+a滑移随着厚向应变量的增加而减弱,且与受到的应力状态无关。

关 键 词：titanium alloy TEXTURE twinning MICROSTRUCTURE DRAWING stress state cold rolling drawing-bulging 

分 类 号：TG146.23[一般工业技术—材料科学与工程]