喷丸强度对DD6单晶高温合金表面完整性的影响  

Effect of shot peening intensities on surface integrity of DD6 single crystal superalloy

作　　者：盖鹏涛 武赟华 曹子文 魏大盛[3] 付雪松[2] GAI Pengtao;WU Yunhua;CAO Ziwen;WEI Dasheng;FU Xuesong(AVIC Manufacturing Technology Institute,Beijing 100024,China;School of Materials Science and Engineering,Dalian University of Technology,Dalian 116024,Liaoning,China;School of Energy and Power Engineering,Beihang University,Beijing 100191,China)

机构地区：[1]中国航空制造技术研究院,北京100024 [2]大连理工大学材料科学与工程学院,辽宁大连116024 [3]北京航空航天大学能源与动力工程学院,北京100191

出　　处：《航空材料学报》2025年第1期53-61,共9页Journal of Aeronautical Materials

基　　金：国家科技重大专项(J2019-Ⅳ-0012-0080)。

摘　　要：单晶涡轮叶片作为航空发动机关键部件,其服役寿命与表面完整性紧密相关,通常需要对其表面进行喷丸强化以满足性能需求。基于此,本工作采用表面轮廓仪、扫描电镜、显微硬度仪和应力测定仪等,系统研究了喷丸前和不同喷丸强度(0.15、0.2 mmA和0.25 mmA)处理对DD6单晶高温合金的表面形貌及粗糙度、近表层微观组织、硬度和残余应力等表面完整性指标的影响规律。结果表明:喷丸强化后的DD6单晶高温合金表面原始机加工痕迹减弱,合金表面粗糙度由0.15mmA试样的0.507μm增大到0.25mmA的0.883μm;在近表面产生了一层梯度塑性变形层,剧烈变形层深度由0.15 mmA试样的45μm逐渐增大到0.25 mmA的98μm;表面硬度值由原始机加工试样490HV逐渐增大到0.25 mmA的738HV,硬化层深度也达到260μm;合金在0.2 mmA喷丸强度下表面残余压应力达到最大,约为-821.2MPa。The service life of single crystal turbine blades,which serve as pivotal components in aero-engines,is intricately tied to their surface integrity.To fulfill performance standards,these blades typically undergo shot peening to meet for reinforcement.This study meticulously examines the impact of surface morphology and various surface integrity indicators—including roughness,near-surface microstructure,hardness,and residual stress—on DD6 single-crystal superalloy before and after undergoing shot peening treatments of varying intensities(0.15,0.2 mmA,and 0.25 mmA).Utilizing a surface profilometer,scanning electron microscope,microhardness tester,and stress tester,we comprehensively analyze these factors.The results show that shot peening diminishes the original machining marks on the DD6 superalloy’s surface,with surface roughness escalating from 0.507μm at 0.15 mmA to 0.883μm at 0.25 mmA.A gradient plastic severe deformation layer emerges near the surface,its depth progressively increasing from 45μm at 0.15 mmA to 98μm at 0.25 mmA.Furthermore,the surface hardness value rises steadily,from 490HV in the original specimen to 738HV at 0.25 mmA,with the hardened layer’s depth also augmenting,from 50μm initially to 260μm at 0.25 mmA.Notably,the alloy attains its peak residual compressive stress of approximately–821.2 MPa on the surface when subjected to a blasting intensity of 0.2 mmA.

关 键 词：DD6单晶高温合金 喷丸强化 表面完整性 残余应力 塑性变形 

分 类 号：V263.5[航空宇航科学与技术—航空宇航制造工程]