固溶时间对Inconel 718合金叶片组织及硬度的影响

Effect of Solid Solution Time on Microstructure and Hardness of Inconel 718 Alloy Blades

以选区激光熔化成型Inconel 718合金叶片为研究对象,利用扫描电子显微镜和显微硬度计对沉积态及热处理态叶片模型进行微观组织和硬度分析。分析结果表明:沉积态叶片主要由不规则晶粒组成,晶粒内部均为胞状亚结构,胞状亚结构的胞壁处富含Nb、Mo元素,合金硬度约为HV300;沉积态叶片经1065℃/2 h/FC热处理后,晶界清晰可见,晶粒内部的胞状亚结构基本消失,合金硬度上升至HV435;进一步延长热处理时间(4 h)后,晶粒内部出现退火孪晶界,合金硬度值略有降低,约为HV415。

Taking the selective laser melting of Inconel 718 alloy blades as the research object,the microstructure and hardness analysis of the blade model in the deposition state and heat treatment state were carried out by scanning electron microscope and microhardness tester.The analysis results show that the sedimentary leaves are mainly composed of irregular grains,the inside of the grains are all cell-like substructures,the cell walls of the cell-like substructures are rich in Nb and Mo elements,and the alloy hardness is about HV300.After heat treatment of 1065℃/2h/FC,the grain boundaries were clearly visible,the cyto-like substructure inside the grains basically disappeared,and the alloy hardness increased to HV435.After further extending the heat treatment time(4h),annealed twin boundaries appear inside the grain,and the alloy hardness value is slightly reduced(about HV415).