Abstract Selective laser melting (SLM) is considered as an important additive manufacturing (AM) technology which can fabricate parts with complex geometry. However, it is difficult to predict the optimal SLM-parameters of metallic materials. In this study, orthogonal experiments were designed to study the influence of SLM-process parameters on the density and fabricated quality of Hastelloy X superalloy. Moreover, the relationship between microstructure evolution and performance of deposited microstructure was studied after heat treatment. The laser power, scanning speed and energy density have a significant effect on the density of the fabricated parts. The optimal parameters for determining Hastelloy X are 250 W laser power, 500 mm/s scanning speed, 100 μm hatch space, and 30 μmlayer thickness. The deposited microstructure is a lamellar microstructure in the horizontal direction and a columnar crystal in the longitudinal direction, and the microstructure is mainly martensite. After solid-solution and aging treatment, grain grows up. Martensite decomposes and the carbide M6C was precipitated during the aging process. The strength of the microstructure decreases slightly due to the growth of grain size.

中文翻译：

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选区激光熔化生产哈氏合金X的组织演变及力学性能

摘要 选择性激光熔化（SLM）被认为是一种重要的增材制造（AM）技术，可以制造具有复杂几何形状的零件。然而，很难预测金属材料的最佳 SLM 参数。在本研究中，设计正交实验来研究 SLM 工艺参数对哈氏合金 X 高温合金的密度和制造质量的影响。此外，研究了热处理后显微组织演变与沉积显微组织性能之间的关系。激光功率、扫描速度和能量密度对制造零件的密度有显着影响。确定 Hastelloy X 的最佳参数是 250 W 激光功率、500 mm/s 扫描速度、100 μm 孵化空间和 30 μmlayer 厚度。沉积组织为横向为层状组织，纵向为柱状晶，显微组织主要为马氏体。经过固溶和时效处理，晶粒长大。时效过程中马氏体分解，碳化物M6C析出。由于晶粒尺寸的增长，显微组织的强度略有下降。