退火时间对Ti-6.0Al-3.0Zr-0.5Sn-1.0Mo-1.5Nb-1.0V钛合金组织及力学性能的影响  

Effect of annealing time on microstructure and mechanical properties of Ti‒6.0Al‒3.0Zr‒0.5Sn‒1.0Mo‒1.5Nb‒1.0V titanium alloy

作　　者：丁平 肖寒[1] 陈磊 刘开元 黄海广[1,2] 余堃 周荣锋 DING Ping;XIAO Han;CHEN Lei;LIU Kai-yuan;HUANG Hai-guang;YU Kun;ZHOU Rong-feng(Faculty of Materials Science and Engineering,Kunming University of Science and Technology,Kunming 650093,China;Yunnan Titanium Industry Co.,Ltd.,Chuxiong 651209,China)

机构地区：[1]昆明理工大学材料科学与工程学院,昆明650093 [2]云南钛业股份有限公司,楚雄651209

出　　处：《工程科学学报》2022年第1期50-58,共9页Chinese Journal of Engineering

基　　金：云南省重大科技专项计划资助项目(202002AB080001-3);国家重点研发计划资助项目(2016YFB0301202)。

摘　　要：针对近α型Ti‒6.0Al‒3.0Zr‒0.5Sn‒1.0Mo‒1.5Nb‒1.0V新型钛合金,在退火温度740℃的基础上,研究了退火时间对其组织与力学性能的影响.结果表明:经过3次真空自耗电弧炉熔炼,三火热轧后得到的板材组织由初生α相基体及β转变组织组成的部分再结晶组织和加工态组织等组成.随着退火时间的增加,退火板材的显微组织均以初生α相为主,且α相所占的比例从81.73%逐渐增加至85.61%,组织中长条状α相逐渐破碎球化,等轴α相开始均匀化、粗化.随着退火时间的增加,退火板材的延伸率逐渐增加,抗拉强度先降低再增加然后又降低,屈服强度先增加后降低,显微硬度先增加后降低.退火时间为1 h时,板材的断口由滑移带、涟波、小等轴韧窝组成,断裂方式为韧性断裂,退火时间大于等于2 h时,板材的断口完全由等轴韧窝组成,断裂方式为韧性断裂.最佳退火工艺为740℃退火2 h,此时板材的抗拉强度、屈服强度、延伸率和显微硬度分别为:984 MPa、941 MPa、15.27%、HV 347.67.研究结果对高强耐蚀钛合金退火工艺的制定有指导作用,为解决钛合金在实际生产中遇到的问题提供了科学依据.The effect of annealing time on the microstructure and mechanical properties of Ti‒6.0Al‒3.0Zr‒0.5Sn‒1.0Mo‒1.5Nb‒1.0V new titanium alloys were studied based on the optimum annealing temperature of 740℃.Results show that after smelting thrice by vacuum consumable arc furnace and thrice hot rolling processes,the microstructure of the sheet is the partial recrystallization structure composed of the primaryαphase,structure ofβtransformation,and the processing status structure.With increased annealing time,the microstructure of the annealed sheet is mainly composed of the primaryαphase,with the proportion of theαphase being gradually increased from 81.73%to 85.61%.The strip-shapedαphase in the microstructure is broken and spheroidized gradually,and an equiaxialαphase begins to be homogenized and coarsened.With the increase of annealing time,the elongation of annealed sheets increases greatly;the tensile strength initially decreases,increases,and then decreases again;and the yield strength and the microhardness first increase and then decrease.When the annealing time is 1 h,the fracture of the sheet has a ductile fracture mode and is composed of slip bands,ripple appearance,and small equiaxial dimples.When the annealing time is more than or equal to 2 h,the fracture exhibits a ductile fracture mode and is completely composed of equiaxial dimples.The optimal annealing process is achieved at 740℃for 2 h,in which the tensile strength,yield strength,elongation,and microhardness of the alloy plate is 984 MPa,941 MPa,15.27%,and HV 347.67,respectively.The main results from this paper can guide the formulation of the annealing process of high-strength corrosion-resistant titanium alloy and provide a scientific basis for solving problems encountered in the actual production of titanium alloy.

关 键 词：钛合金 轧制 退火时间 微观组织 力学性能 

分 类 号：TG146.23[一般工业技术—材料科学与工程]