激光与光电子学进展, 2018, 55 (8): 081405, 网络出版: 2018-08-13
激光增材制造薄壁结构件工艺及性能的研究 下载: 689次
Study on Process and Properties of Thin-Walled Structure Part by Laser Additive Manufacturing
激光技术 激光增材制造 薄壁结构件 粉末负离焦 显微组织 力学性能 laser technique laser additive manufacturing thin-walled structure part negative defocusing of powder microstructure mechanical properties
摘要
利用激光增材制造技术成形了薄壁结构件,采用粉末负离焦的方法解决了薄壁结构件成形过程中两端塌陷的问题,并分析了薄壁结构件的显微组织和力学性能。结果表明,当激光功率为1400 W,扫描速率为0.6 m·min-1,送粉速率为9.5 g·min-1时,获得了理想的单道熔覆层形貌。当单层提升量为0.57 mm时,薄壁结构件的表面无粘粉,无氧化色。熔覆层的高度和粉末利用率随粉末正负离焦量的增大而减小。薄壁结构件的显微组织主要为外延生长的树枝晶,离基体较近部位的枝晶较为粗大,而顶部为等轴晶组织。薄壁结构件的硬度高于基体的,且离基体较近部位的硬度较小。
Abstract
Based on the laser additive manufacturing technology, the thin-walled structural parts are formed. The method of negative defocusing of powder is adopted to solve the both-end collapse problem in the forming process of thin-walled structural parts. The microstructure and mechanical properties of thin-walled structural parts are analyzed. The results show that the ideal morphology of single track cladding layer is obtained at laser power of 1400 W, scanning speed of 0.6 m·min-1 and feeding speed of 9.5 g·min-1. The surface of the thin-walled structural part is free of powder and has no oxidation color when the lifting capacity of single layer is 0.57 mm. The height of cladding layer and the using efficiency of powder decrease with the increase of positive and negative powder defocusing. The microstructure of the thin-walled structural part is mainly dendrites growing epitaxially and the dendrites near the substrate are relatively coarse, however at the top is equiaxed grain structure. The hardness of the thin-walled structural part is higher than that of the substrate, and the hardness near the substrate is relatively smaller.
肖鱼, 路媛媛, 郭溪溪, 王涛, 杜锦铮, 刘德健. 激光增材制造薄壁结构件工艺及性能的研究[J]. 激光与光电子学进展, 2018, 55(8): 081405. Xiao Yu, Lu Yuanyuan, Guo Xixi, Wang Tao, Du Jinzheng, Liu Dejian. Study on Process and Properties of Thin-Walled Structure Part by Laser Additive Manufacturing[J]. Laser & Optoelectronics Progress, 2018, 55(8): 081405.