激光粉末床熔融GH4169合金成形工艺快速优化及性能研究

Rapid Optimization of Forming Process and Performance Study for Laser Powder Bed Fusion of GH4169 Alloy

摘要: 采用正交实验 + 单因素实验、以致密度为评价指标的成形工艺快速优化方法，开展了激光粉末床熔融GH4169的成形工艺实验，使用优化后的工艺参数成形了GH4169试样，观测了GH4169的金相组织和微观组织，测试了GH4169的室温和650℃高温拉伸性能。结果表明：在一定范围内，当激光功率上升、扫描速度下降、扫描间距下降时，GH4169的致密度会呈现出先明显上升后略微下降的趋势；采用该成形工艺快速优化方法得到的工艺窗口，即激光功率305 W、扫描速度960 mm/s、单层厚度0.05 mm、扫描间距0.1 mm时，其室温和650℃高温下的力学性能均能达到国标GH4169合金的锻件要求。

Abstract: A rapid optimization method for forming processes was developed using orthogonal experiments combined with single-factor experiments, with density as the evaluation index, to carry out the forming process experiment of laser powder bed fusion (LPBF) of GH4169. GH4169 specimens were fabricated using optimized process parameters, followed by observations of their metallographic and microstructures, and tensile property tests at room temperatures and 650˚C. Results show that within a specific range, the density of GH4169 first significantly increases and then slightly decreases with the increase in laser powder, decrease in scanning speed, and decrease in scanning spacing. When using the process window obtained via this rapid optimization method for forming processes—laser powder of 305 W, scanning speed of 960 mm/s, single-layer thickness of 0.05 mm, and scanning spacing of 0.1 mm—the mechanical properties at both room temperature and 650˚C meet the requirements for forged parts of the national standard GH4169 alloy.