Research on hole inhibiting mechanism of 5A06 aluminum alloy during laser oscillating fuse deposition forming

• Published in: Optics and laser technology Vol. 164; p. 109530
• Main Authors: Song, Yongda, Yuan, Chengwei, Huang, Wenhao, Zhao, Yun, Jia, Yazhou
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.09.2023
• Subjects: Additive manufacturing; Circular oscillation; Laser fuse; Molten pool flow; Numerical simulation; Porosity; Circular oscillation; Numerical simulation; Additive manufacturing; Porosity; Molten pool flow; Laser fuse
• ISSN: 0030-3992; 1879-2545
• DOI: 10.1016/j.optlastec.2023.109530

•Numerical simulation and experimental comparative analysis of material increment manufacturing with oscillating laser fuse.•The oscillating laser increases the possibility of air discharging from the small holes, effectively reducing porosity.•After adding the swing, the workpiece surface finish and flatness are better and the forming height is higher.•High-frequency circular swing will be more effective than low-frequency circular swing in inhibiting porosity. To meet the requirements of aerospace components integration and lightweight, it is urgent to improve the forming and manufacturing technology for lightweight materials. Laser fuse material increasing technology can satisfy the integrated forming of large and complex components, but due to the high energy of the laser, pore appears in aluminum alloy after rapid cooling after heat melting, which leads to the high porosity of formed components and poor overall deposition performance. This paper proposes the effect of reducing workpiece porosity by adding laser oscillation in laser fuse material increasing technology. The research simulates the deposition process of laser fuse material increasing under different process parameters, compares and analyses the experiment and simulation results of laser swing fuse material increasing, and summarizes the influence of swing parameters on laser fuse forming by combining the experiment overall forming morphology, section morphology and simulation results. The results show that during the manufacturing process of laser fuse material increasing, due to the heating and impact of the laser, depressions are formed at the front of the melting pool, and the contact surface between the depression and air layer is blocked by the melting pool, then small holes are formed so that the air inside the small holes can not escape completely and then form pores. When adding a laser circular swing, the shallower the orifice position, the faster the pressure diffusion inside the molten pool, the higher the possibility of the orifice discharging air, and the smaller the number and size of the pore. The surface finish and flatness of the workpiece are also better than those without a swing. High-frequency circular oscillation increases the possibility of hole wall breakage, makes the air inside the hole exhaust longer, and suppresses the pore better. The research is helping to improve the understanding of the deposition process in laser-oscillating augmentation manufacturing of aluminum alloy, to reduce the pore problems encountered in laser-fused augmentation of aluminum alloy, and to provide the selection of corresponding process parameters.