激光冲击波对单晶合金抗热腐蚀性能的影响  

Effect of laser shock wave on thermal corrosion resistance of single crystal alloy

作　　者：胡宪亮 乔红超[1,2] 赵吉宾 陆莹[1,2] 吴嘉俊[1,2,3] 杨玉奇 HU Xianliang;QIAO Hongchao;ZHAO Jibin;LU Ying;WU Jiajun;YANG Yuqi(State Key Laboratory of Robotics,Shenyang Institute of Automation,Chinese Academy of Sciences,Shenyang 110016,China;Institutes for Robotics and Intelligent Manufacturing,Chinese Academy of Sciences,Shenyang 110169,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院沈阳自动化研究所机器人学国家重点实验室,沈阳110016 [2]中国科学院机器人与智能制造创新研究院,沈阳110169 [3]中国科学院大学,北京100049

出　　处：《航空学报》2022年第4期496-507,共12页Acta Aeronautica et Astronautica Sinica

基　　金：国家自然科学基金(51875558);国家基金委-辽宁省联合基金(U1608259)。

摘　　要：针对镍基单晶高温合金叶片服役时受高温腐蚀工作环境影响极易疲劳断裂问题,研究了不同激光冲击次数下激光冲击强化对单晶合金抗热腐蚀性能的影响。利用显微硬度仪测量激光冲击前后合金纵截面的显微硬度;借助扫描电子显微镜(SEM)和能谱仪(EDS)观察和分析腐蚀层表面及纵截面的微观组织,并结合X射线衍射仪(XRD)确定腐蚀层表面相结构。实验结果表明:经激光冲击强化后,合金表面显微硬度和截面硬度影响层深度均随激光冲击次数的增加而增大;在短时热腐蚀实验中,当激光冲击次数增加到1次、2次、3次后,合金腐蚀最大单位面积增重量分别从未冲击合金的2.87mg·cm^(-2)降低到2.17、1.81、1.10mg·cm^(-2),腐蚀层深度分别从91μm降低到65、41、27μm,且表面腐蚀坑的尺寸、深度和数量明显下降,保护性氧化膜致密性得到提高。所得结果表明激光冲击强化能有效提高900℃/75%Na_(2)SO_(4)-25%NaCl盐膜条件下单晶合金的抗热腐蚀性能。Nickel-based single crystal superalloy blades are prone to fatigue and fracture in the high-temperature corrosion working environment during service.The effect of laser shock processing on the thermal corrosion resistance of single crystal alloy with different number of laser shock was studied.The microhardness of the longitudinal section of the alloy before and after laser shock was measured by using the microhardness tester.The microstructures of the surface and longitudinal section of the corrosion layer were observed and analyzed by using the Scanning Electron Microscope(SEM)and Energy Dispersive Spectrometer(EDS),and the surface phase structure of the corrosion layer was determined by using the X-Ray Diffraction(XRD).The experimental results show that after the alloy was strengthened by laser shock,the surface microhardness and section hardness influence layer depth of the alloy both increase with the increase of the number of laser shock.During the short-term thermal corrosion experiment of the alloy,when the number of laser shock increased to 1,2,and 3 times,the maximum weight gain per unit area of corroded alloy decreased from the value of alloy without laser shock 2.87 mg·cm^(-2)to 2.17,1.81,1.10 mg·cm^(-2);the corrosion layer depth reduced from 91μm to 65,41,27μm;the size,depth and number of surface corrosion pits were significantly reduced,and compactness of the protective oxide film was improved.The results show that laser shock processing can effectively improve the thermal corrosion resistance of single crystal alloy under the condition of 900℃/75%Na_(2)SO_(4)-25%NaCl salt film.

关 键 词：激光冲击强化 单晶合金 短时热腐蚀 显微硬度 显微组织 

分 类 号：V216.8[航空宇航科学与技术—航空宇航推进理论与工程]