Cai Gaoshen, Liu Hui, Peng Kai, Wang Bingxu, Hu Biao
School of Mechanical Engineering, Zhejiang Sci-Tech University, Hangzhou, 310018, Zhejiang, China.
Sci Rep. 2024 Aug 26;14(1):19776. doi: 10.1038/s41598-024-70883-9.
Lightweight thin-walled parts are widely used in the aviation and aerospace industries, and with the further increase in the complexity of their features, the traditional manufacturing process can no longer fully meet the high requirements of industrial component manufacturing. In this work, thin-walled parts are processed by Laser based powder bed fusion of metals (PBF-LB/M), and the effects of process parameters on residual stress, hardness, mechanical properties and microstructure of thin-walled parts are systematically investigated. The simulation results show that the maximum equivalent residual stresses are distributed in the combination of the solid and the substrate, and the minimum equivalent residual stresses are mainly distributed in the top two ends and the middle part of the solid, and the stress distribution is symmetrical. In addition, the maximum equivalent residual stress increases with the increase of laser power, and decreases with the increase of scanning spacing or scanning speed. The experimental results show that with the increase of laser energy density, the tensile strength and yield strength of thin-walled parts show a tendency of increasing first and then decreasing. Finally, high-quality thin-walled parts were successfully fabricated by the optimized process parameters, and their tensile and yield strengths were increased by 6.1% and 15.9%, respectively.
轻质薄壁零件在航空航天工业中广泛应用，随着其特征复杂性的进一步增加，传统制造工艺已无法完全满足工业零部件制造的高要求。在这项工作中，采用基于激光的金属粉末床熔融（PBF-LB/M）工艺对薄壁零件进行加工，并系统研究了工艺参数对薄壁零件残余应力、硬度、力学性能和微观结构的影响。模拟结果表明，最大等效残余应力分布在实体与基板的结合处，最小等效残余应力主要分布在实体的顶部两端和中部，且应力分布对称。此外，最大等效残余应力随激光功率的增加而增大，随扫描间距或扫描速度的增加而减小。实验结果表明，随着激光能量密度的增加，薄壁零件的抗拉强度和屈服强度呈现先增大后减小的趋势。最后，通过优化工艺参数成功制造出了高质量的薄壁零件，其抗拉强度和屈服强度分别提高了6.1%和15.9%。
