热等静压对激光粉末床熔融增材制造 GH3536 合金组织与缺陷演变的影响

Heat treatment is necessary for GH3536 components fabricated by laser powder bed fusion. However, its ability to regulate defects generated in additive manufacturing is limited, which restricts the fatigue life of the material. Therefore, it is essential to conduct post-processing research to synergistically control the defects, microstructure and properties. μ-CT was used to characterize the defects in the as-deposited, heat-treated, and hot isostatically pressed(HIP) states of the components in situ. The microstructure, tensile properties, and fatigue performance of the components in each state were also characterized. The results revealed that the porosity increased from 0.08% in the as-deposited state to 0.12% after heat treatment, while it decreased to 0.03% after HIP. Additionally, the fatigue crack growth rate was reduced, and the toughness improved due to enhanced grain boundary coordination and deformation capability. The mechanical properties at both room temperature and high temperature met the service requirements for aerospace hot-end components. Furthermore, post-processing effectively refined the grain size, with the average grain sizes of the as-deposited and HIP states being 35.9 μm and 24.3 μm, respectively. The complete additive manufacturing and post-processing process proposed in this study provides valuable guidance for the engineering application of GH3536 components.