The impact of laser shock peening(LSP)on the microstructure and oxidation behavior of the nickel-based single crystal superalloy was investigated.The samples underwent LSP treatment,fol-lowed by oxidation for 10 and 150 h at 980℃.The microstructure,microhardness,and oxidation morphol-ogy of this alloy without and with LSP treatment were comparatively examined.Finally,the mechanism by which LSP affects the oxidation behavior of this alloy was elucidated.The result shows that after a single impact,the surface of the specimen manifested some grid-like dislocations distribution,alongside an in-crement in microhardness from an initial value of 420 HV to 495 HV.After three impacts,the disloca-tions on the surface appeared more uniformly distributed with evident entanglement,culminating in an el-evation of surface microhardness to approximately 590 HV.Furthermore,the dislocations generated on the surface by LSP promoted the formation of diffusion pathways during the oxidation process,which fa-cilitated the early formation of a continuous protective oxide scale.It decreased the formation of poor Al pits,which resulted from the development of a protective oxide scale in the subsequent stages of oxida-tion,thereby reducing the spalling of the oxide scale.
关键词
激光冲击强化/微观演变/镍基单晶高温合金/元素扩散/氧化
Key words
laser shock peening/microstructural evolution/nickel-based single crystal superalloy/el-ement diffusion/oxidation
维普
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