为了研究激光选区熔化GH3536合金组织对零件力学性能的影响,采用不同批次粉末制备激光选区熔化GH3536合金,分析显微组织、测试室温拉伸性能和高温持久性能,并分析失效机理。结果表明,激光选区熔化GH3536合金显微组织主要为奥氏体相,在晶粒内部和晶界处析出M₂₃C₆碳化物。晶粒尺寸增大,晶界数量减少,导致室温拉伸强度降低,但高温持久性能得到提升。块状碳化物分布在晶界会降低激光选区熔化GH3536合金室温塑性和高温持久性能;链状碳化物能够强化晶界,使合金具有较高的室温塑性和高温持久性能。

This study aims to investigate the effect of microstructure on mechanical properties of the GH3536 alloy fabricated by selective laser melting (SLM) technology. Different powder batches are utilized to fabricate the specimens. The microstructures, room temperature tensile property, and high temperature endurance performance are then tested, and the invalidation mechanism is analyzed. The results show that the microstructure of the SLM GH3536 alloy is mainly austenitic phase with M23C6 inside the grain and at the grain boundary. The amount of grain boundary decreases with the increasing grain size, leading to an improvement of the high temperature endurance performance, but a degradation of the tensile property at room temperature. The massive carbide at the grain boundary will reduce the room temperature tensile property and the high temperature endurance performance of the SLM GH3536 alloy. However, the chain carbide at the boundary can improve the room temperature tensile property and high temperature endurance performance.