机械喷丸+激光冲击复合表面改性TC4钛合金表面完整性研究  

Surface Integrity Research of TC4 Titanium Alloy Treated by Laser Shock Peening and Shot Peening

作　　者：安宏亮 刘梦金 牛志强 付雪松[1,3] 盖鹏涛 周文龙 陈国清[1] AN Hong-liang;LIU Meng-jin;NIU Zhi-qiang;FU Xue-song;GAI Peng-tao;ZHOU Wen-long;CHEN Guo-qing(School of Materials Science and Engineering,Dalian University of Technology,Liaoning Dalian 116024,China;AVIC Manufacturing Technology Institute,Beijing 100024,China;Dalian Technology(Yingkou)Advanced Material Engineering Center Co.,Ltd.,Liaoning Yingkou 115004,China)

机构地区：[1]大连理工大学材料科学与工程学院,辽宁大连116024 [2]中国航空制造技术研究院,北京100024 [3]大连理工(营口)新材料工程中心有限公司,辽宁营口115004

出　　处：《失效分析与预防》2024年第5期337-345,共9页Failure Analysis and Prevention

基　　金：国家自然科学基金(51975084);国家科技重大专项(J2019-Ⅳ-0012-0080);辽宁省自然科学基金(2022-YKLH-04)。

摘　　要：为提升航空发动机钛合金叶片性能,采用机械喷丸、激光冲击及复合强化对TC4钛合金表面进行改性处理,并研究复合强化顺序及参数对钛合金表面完整性的影响。结果表明:复合喷丸强化钛合金的表层残余压应力场具有单独机械喷丸、激光冲击的耦接特征,近表面残余应力场接近机械喷丸,近基体区域的残余应力场接近激光冲击,即整体残余应力场深度大、表面应力值高。复合强化顺序影响残余应力层中间段的应力值分布,先激光冲击后机械强化的残余应力相对更高。机械喷丸强度较低时,强化顺序对表面粗糙度影响不大;机械喷丸强度较高时,强化顺序对表面粗糙度影响大。机械喷丸强化后的试样近表面组织内形成小角度晶界和少量孪晶,激光冲击强化试样近表面仅形成小角度晶界,但没有观测到孪晶,而先激光冲击的复合强化试样产生孪晶较多。In order to study the composite shot peening strengthening to improve the performance of aero-engine titanium alloy blades,the surface modification of TC4 titanium alloy was carried out by mechanical shot peening and laser shock peening.The effects of surface treatment sequence and process parameters on the surface integrity of titanium alloy were studied.The results show that the residual compressive stress field on the surface of composite shot peening strengthened titanium alloy has a coupled characteristic of separate mechanical shot peening and laser shock.The residual stress field feature near the surface is close to mechanical shot peening,and the residual stress field feature near the substrate is close to laser shock peening.The depth of the overall residual stress field is large and the surface stress value is high.The order of composite strengthening affects the distribution of stress values in the middle section of the residual stress layer.The residual stress after the first laser shock and then mechanical strengthening is relatively higher.When the mechanical shot peening strength is low,the process sequence has little effect on the surface roughness.When the mechanical shot peening intensity is high,the sequence has a great influence on the surface roughness.After the mechanical shot peening strengthening,the small angle grain boundaries and a little twinning formed in the near surface of the sample.Laser shock strengthening only resulted in small angle grain boundaries near the surface of sample,but no twinning was observed.The composite strengthening sample with the laser shock first produced more twinning.

关 键 词：TC4钛合金 机械喷丸 激光强化 复合强化 表面完整性 

分 类 号：TG668[金属学及工艺—金属切削加工及机床]