元素偏析对TB6钛合金微观组织和力学性能的影响规律  

The influence law of elemental segregation on the microstructure and mechanical properties of TB6 titanium alloy

作　　者：徐平安 刘向宏[2] 康家瑞 赵宁 孙上清 王凯旋[2] 史蒲英[2] 王涛[2] XU Ping’an;LIU Xianghong;KANG Jiarui;ZHAO Ning;SUN Shangqing;WANG Kaixuan;SHI Puying;WANG Tao(AVIC Changhe Aircraft Industry(Group)Co.,Ltd.,Jingdezhen 333002,Jiangxi,China;Western Superconducting Technologies Co.,Ltd.,Xi’an 710018,China)

机构地区：[1]昌河飞机工业(集团)有限责任公司,江西景德镇333002 [2]西部超导材料科技股份有限公司,西安710018

出　　处：《有色金属科学与工程》2025年第2期255-263,共9页Nonferrous Metals Science and Engineering

基　　金：秦创原引用高层次创新创业人才项目(QCYRCXM-2023-003);西安市博士后创新基地资助项目(2023-8)。

摘　　要：稳定元素偏析缺陷(β斑)对近β型钛合金的力学性能具有显著影响。为揭示TB6钛合金中的β斑对TB6钛合金力学性能的影响规律,分别对含有β斑和不含有β斑的TB6钛合金进行室温力学性能测试,并通过原位拉伸试验测试力学性能,采用扫描电子显微镜(SEM)和能谱仪(EDS)分析显微组织,通过显微组织演变分析β斑对力学性能的影响机理。结果表明:含有β斑的试样具有更高的抗拉强度和屈服强度,分别为1170 MPa和1 107 MPa,相比于无β斑缺陷试样分别增加3.90%和3.79%;含有β斑试样的延伸率和断面收缩率分别为5.20%和15.00%,相比于无β斑缺陷试样降低了66.67%和22.58%。由于TB6钛合金中Fe元素的富集,导致β斑区域内等轴α相含量相对较低而片层α相含量较高,因此含β斑的TB6钛合金具有更高的拉伸强度。通过缺口原位拉伸试验发现,不含β斑的试样在加载力达到1937 N后观察到明显裂纹,含β斑的试样在加载力达到1760 N时即可观察到明显裂纹,伴随力的加载,裂纹进一步拓展直至断裂,表明β斑对TB6钛合金的强塑性具有显著影响。stable element segregation defects(β fleck) significantly impact on the mechanical properties of near-β-type titanium alloys.In order to reveal the influence of β flecks on the mechanical properties of TB6 titanium alloy,TB6 titanium alloys with and without β flecks were subjected to mechanical testing at room temperature.In situ tensile tests,scanning electron microscopy(SEM),and energy dispersive spectroscopy(EDS) were used to analyze the microstructure and the evolution of microstructure to investigate the mechanism of β flecks' influence on mechanical properties.The specimens with β flecks had higher tensile strength and yield strength,1170 MPa and 1107 MPa,respectively,showing an increase of 3.90% and 3.79% compared to those without β flecks defects.The elongation and cross-sectional shrinkage of the specimens with β flecks were 5.20% and 15.00%,respectively,reduced by 66.67% and 22.58% compared to those without β flecks.Due to the enrichment of Fe element in the TB6 titanium alloy,the content of equiaxed α phase in the β fleck area was relatively low and the content of lamellar α phase was high,leading to the higher tensile strength for TB6 titanium alloy with β flecks.The in-situ notch tensile test showed that apparent cracks were observed in the samples without β flecks when the loading force reached 1 937 N,and obvious cracks were observed in the samples containing β flecks when the loading force reached 1760 N.As the force increased,the cracks further expanded until fractured,indicating that β flecks significantly affected on the strength and ductility of TB6 titanium alloy.

关 键 词：TB6钛合金 β斑 原位拉伸 

分 类 号：TG314[金属学及工艺—金属压力加工]