基于缺陷三维成像的电子束熔丝增材制造钛合金疲劳寿命模型  

Fatigue Life Model of Electron Beam Fusion Additive Manufactured Titanium Alloy Using 3D Defect Tomography

作　　者：方燕玲 谢成 吴圣川[2] 张杰 杨光 齐世文 李飞 FANG Yanling;XIE Cheng;WU Shengchuan;ZHANG Jie;YANG Guang;QI Shiwen;LI Fei(Chengdu Aircraft Industrial(Group)Co.,Ltd.,Chengdu 610092,China;State Key Lab of Traction Power,Southwest Jiaotong University,Chengdu 610031,China;AVIC Manufacturing Technology Institute,Beijing 100024,China)

机构地区：[1]航空工业成都飞机工业(集团)有限责任公司,成都610092 [2]西南交通大学,牵引动力国家重点实验室,成都610031 [3]中国航空制造技术研究院,北京100024

出　　处：《机械工程材料》2021年第4期72-80,共9页Materials For Mechanical Engineering

基　　金：国家自然科学基金大科学装置联合基金培育项目(U2032121);国家重点研发计划项目(2016YFB1100400);装备预研航空科学基金项目(6141B051506);国防基础科研计划项目(JCKY2018205B027)。

摘　　要：应用高分辨率同步辐射三维X射线成像技术获取电子束熔丝增材制造Ti-6Al-4V合金的特征参数,结合高周疲劳试验分析缺陷对合金疲劳性能的影响;考虑缺陷特征参数对已有Z参数疲劳寿命模型进行修正,提出了X参数疲劳寿命模型。结果表明:所制造Ti-6Al-4V合金存在气孔及未熔合缺陷;不同应力水平下合金的疲劳寿命均存在较大的离散性,50%存活率下合金的疲劳极限为679MPa,多数疲劳裂纹萌生于气孔、未熔合缺陷处;由X参数疲劳寿命模型得到的X参数-疲劳寿命曲线的线性拟合相关系数为08.785,比由Z参数疲劳寿命模型得到的提高了近20%,疲劳寿命离散性显著降低,模型的预测精度显著提高。The charcteristic parameters of defects in electron beam fusion additive manufactured Ti-6Al-4V alloy were obtained by high-resolution synchrotron radiation 3D X-ray tomography technique.Combining with high cycle fatigue tests,the influence of defects on fatigue properties of the alloy was analyzed.The Z-parameter fatigue life model was modified by considering defect characteristic parameters,and an X-parameter fatigue life model was proposed.The results show that there were porosity and incomplete fusion defects in the manufactured Ti-6Al-4V alloy.The fatigue life of the alloy had significant dispersion in different stress levels and the fatigue limit with 50% survival rate was 679 MPa.Most of the fatigue cracks originated at the porosity and incomplete fusion defects.The linear fitting correlation coefficient of X-parameter-fatigue life curve by X-parameter fatigue life model was 0.878 5,and was improved by nearly 20% compared with the Z-parameter fatigue life model,the dispersion of fatigue life significantly decreased,and the prediction accuracy of the model was significantly improved.

关 键 词：电子束熔丝增材制造 三维X射线成像 缺陷 疲劳寿命模型 

分 类 号：TG146.2[一般工业技术—材料科学与工程]