通过选区激光熔化技术制备了GH3536镍基高温合金,并在900 ℃不同保温时间下(0.5,1.0,1.5,2.0,2.5 h)进行热处理。利用光镜、X射线衍射、电子背散射衍射、纳米压痕和维氏硬度分析了沉积态和不同热处理态的微观组织和力学性能。结果发现,沉积态组织内部存在细小枝晶,经热处理后部分消失,部分转变为再结晶晶粒。沉积态横截面(Z面)晶粒主要沿着(111)面和(001)面生长,热处理后的晶粒主要沿着(101)面生长。沉积态硬度为303 HV0.5,杨氏模量为218 GPa,经热处理后杨氏模量基本不变,但硬度显著降低,为273 HV0.5左右。
GH3536 nickel-based superalloy was fabricated by selective laser melting technology (SLM) and heat treated at 900 ℃ for different holding times (0.5 h, 1.0 h, 1.5 h, 2.0 h, 2.5 h). Optical microscopy, X-ray diffraction, electron backscatter diffraction, nanoindentation and Vickers hardness were used to analyze the microstructure and mechanical properties of the deposition and different heat treatment states. The results show that there are fine dendrites in the deposited microstructure, some of them disappear after heat treatment, while some of them change into recrystallized grains. Grains of horizontal plane (Z plane) in the deposited state mainly grow along the (111) plane and (001) plane. After heat treatment, the grains mainly grow along the (101) plane. The hardness of the deposited sample is 303 HV0.5, and Young's modulus is 218 GPa. After heat treatment, Young's modulus is basically unchanged, but the hardness significantly decreases to about 273 HV0.5.