热处理对新型医用Ti-3Zr-2Sn-3Mo-25Nb钛合金显微组织与力学性能的影响  

Effect of Heat Treatment on Microstructure and Mechanical Properties of a New Type of Ti-3Zr-2Sn-3Mo-25Nb Medical Titanium Alloy

作　　者：程军 于振涛[2,3] 牛金龙[2,3] 余森 王岚[4,5] 李思莹 

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西西安710072 [2]西北有色金属研究院,陕西西安710016 [3]陕西省医用金属材料重点实验室,陕西西安710016 [4]西安建筑科技大学冶金工程学院,陕西西安710055 [5]东北大学材料科学与工程学院,辽宁沈阳110819

出　　处：《稀有金属与硬质合金》2018年第1期49-55,共7页Rare Metals and Cemented Carbides

基　　金：陕西省工业科技攻关项目(2015GY152;2016SF237;2016SF105);陕西省重点科技创新团队计划(2016KCT-30);重大科技成果转化引导专项(2016KTCG01-04)

摘　　要：分析了不同热处理制度对新型医用Ti-3Zr-2Sn-3Mo-25Nb合金显微组织与力学性能的影响。结果表明:经(α+β)两相区固溶处理后,合金主要由初生α相和β相组成;初生α相尺寸短小,以颗粒状形式出现在晶粒内部和晶界附近。在实验参数范围内,升高固溶温度导致初生α相的体积分数降低,β相的体积分数增加。经β单相区固溶处理后,合金主要由单一β相组成;随着固溶温度升高,β相晶粒逐渐长大,晶粒尺寸约为25μm。经(α+β)两相区固溶+时效处理后,在β相基体上析出针状α相,尺寸细小,呈交叉排列。经β单相区固溶+时效处理后,在β相晶界附近和晶粒内部析出尺寸大小不一的细针状α相;晶界附近析出的α相具有一定的取向,晶粒内部析出的α相横纵交错,大小不均匀。经固溶处理后,合金获得中等水平的强度和较好的塑性;随着固溶温度的升高,合金的抗拉强度和屈服强度逐渐减小,塑性和弹性模量逐渐增加。经(α+β)两相区固溶处理后,合金的抗拉强度与屈服强度之差(Rm-Rp0.2)较β单相区固溶处理后的大。经(α+β)两相区固溶+时效处理后的合金强度增量高于β单相区固溶+时效处理后的合金强度增量。在相同时效条件下,随着固溶温度升高,合金的强度和模量逐渐减小,延伸率基本保持不变。经780℃/30min固溶空冷+480℃/6h时效空冷处理后合金的弹性模量达最小值(E=64GPa),最接近于人体自然骨骼等硬组织的弹性模量。The effect of different heat treatment systems on microstructure and mechanical properties of a new type of Ti-3 Zr-2 Sn-3 Mo-25 Nb medical titanium alloy was analyzed.The results show that the alloy is composed of primaryαphase andβphase after solution treatment in（α＋β）two-phase field.Primaryαphase has short and fine size,precipitated inside the grains and around the grain boundary in granular form.As the rise of the solution treatment temperature,the volume fraction of primaryαphases is decreasing and the volume fraction ofβphases is increasing.The alloy is composed of singleβphase after solution treatment inβfield.As the rise of the solution treatment temperature,the size ofβphase grains is increasing and it is about 25μm.Acicularαphase with fine size and cross arrangement is precipitated in theβphase matrix after solution treatment in（α＋β）two-phase field plus aging treatment.Fine acicularαphase with different sizes is precipitated around grain boundary and inside the grains after solution treatment inβfield plus aging treatment.Theαphase precipitated around grain boundary has a definite orientation.Theαphase precipitated inside the grains is crisscrossed and its size is nonuniform.The alloy obtains a medium strength and better ductility after solution treatment.As the rise of solution treatment temperature,tensile strength and yield strength of the alloy are decreasing,while the ductility and elasticity modulus are increasing.The difference value between tensile strength and yield strength（Rm-Rp0.2）is greater after solution treatment in（α＋β）field than that after solution treatment inβfield.Strength increment of the alloy is higher after solution treatment in（α＋β）field plus aging treatment than that after solution treatment inβfield plus aging treatment.Under the same aging conditions and as the rise of solution treatment temperature,the strength and modulus of the alloy are decreasing,and the elongation rate remains unchanged.The elastic modulus of the allo

关 键 词：医用材料 近Β型钛合金 Ti-3Zr-2Sn-3Mo-25Nb 热处理 显微组织 力学性能 

分 类 号：TG146.23[一般工业技术—材料科学与工程]