摘要
以激光选区熔化技术(SLM)成型TC4钛合金为研究对象,通过光学显微镜(OM)、扫描电镜(SEM)和电子万能试验机等测试分析方法,研究了热等静压处理温度对TC4钛合金材料微观组织和力学性能的影响。结果表明,SLM态TC4钛合金横截面微观组织由等轴状初生β晶粒组成,纵截面微观组织由呈外延生长的柱状初生β晶粒组成。晶粒内部以不同取向的针状α′马氏体相为主,纳米点状β相在初生马氏体间形核生长。在α+β两相区温度进行热等静压处理,TC4钛合金的组织由α相和β相组成。随着热等静压处理温度的升高,板条状α相粗化成短棒状,β相含量增加且发生一定粗化。随着热等静压处理温度的升高,材料的抗拉强度和屈服强度呈现降低的趋势,断面收缩率也呈下降趋势。热等静压处理工艺为910℃-110 MPa-2 h的TC4钛合金可获得最优的强韧性匹配。
Using optical microscope(OM), scanning electron microscope(SEM) and electronic universal testing machine, the effect of hot isostatic pressing(HIP) temperature on the microstructure and mechanical properties of the TC4 titanium alloy formed by laser selective melting(SLM) was investigated. The results show that the cross section microstructure of the TC4 titanium alloy by SLM is composed of equiaxed primary β grains, the longitudinal section microstructure is composed of columnar primary β grains with epitaxial growth. The inside of the grains is dominated by acicular α′ martensite phases with different orientations, nano-dot β phase nucleates and grows between the primary martensite. The structure of the TC4 titanium alloy is composed of α phase and β phase when HIP is performed at temperature of the α+β phase region. With the increase of HIP temperature, the lath α-phase coarsens into short rod, the content of β phase increases and coarsens, the tensile strength and yield strength of TC4 shows a decreasing trend, section shrinkage also shows a decreasing trend. When HIP at 910 ℃ with a pressure of 110 MPa for 2 h, the TC4 titanium alloy obtains the best matching of strength and toughness.
作者
吕周晋
李好峰
车立达
吴战芳
翟一多
崔晓敏
李向阳
LüZhoujin;Li Haofeng;Che Lida;Wu Zhanfang;Zhai Yiduo;Cui Xiaomin;Li Xiangyang(Cisri Hipex Technology Co.,Ltd.,Beijing 100081,China;China Iron&Steel Research Institute Group,Beijing 100081,China)
出处
《金属热处理》
CAS
CSCD
北大核心
2022年第6期138-142,共5页
Heat Treatment of Metals
关键词
热等静压
激光选区熔化
TC4钛合金
微观组织
力学性能
hot isostatic pressing
selective laser melting
TC4 titanium alloy
microstructure
mechanical properties
