激光与光电子学进展, 2019, 56 (10): 101401, 网络出版: 2019-07-04
基于选区激光熔化的316L不锈钢的裂纹形成规律及机理 下载: 1383次
Crack Formation Law and Mechanism in Selective Laser Melting of 316L Stainless Steels
激光技术 选区激光熔化 线能量密度 裂纹 气泡 孔隙 缺陷分析 laser technology selective laser melting line energy density crack bubble pore defect analysis
摘要
采用选区激光熔化(SLM)技术制备了316L不锈钢,分析了激光功率、扫描速度和扫描间距与成形件裂纹的变化规律,研究了裂纹形貌、化学成分、析出相种类和晶粒尺寸,获得了不同位置处裂纹的组织结构和形成机理。结果表明,裂纹主要为微孔聚集形裂纹、气泡聚集形裂纹和热裂纹。随着线能量密度的增大,微孔聚集形裂纹和气泡聚集形裂纹数目先增加后减少,热裂纹单向逐渐增多。优化工艺参数(线能量密度为222.2 J/m, 激光功率为200 W, 激光扫描速率为900 mm/s)下,获得了无裂纹、无气泡、少量孔隙的成形件。
Abstract
Selective laser melting (SLM) is used to prepare 316L stainless steels. Further, the effects of laser power, scanning speed, and scanning spacing on the formation of cracks are studied in detail, the morphologies, chemical compositions, types of the precipitated phases, and grain sizes of the cracks are discussed, and the microstructures and formation mechanism of the cracks at different positions are presented. The results denote that the cracks mainly include micropore aggregation cracks, bubble aggregation cracks, and hot cracks. With the increase of linear energy density, the numbers of micropore aggregation cracks and bubble aggregation cracks are observed to initial increase and subsequent decrease; however, the number of hot cracks is observed to unidirectional increase. Under the optimal process parameters (a linear energy density of 222.2 J/m, a laser power of 200 W, and a laser scanning speed of 900 mm/s), the samples containing a small number of pores but no lacking cracks and no bubbles are obtained.
潘露, 张成林, 王亮, 刘麒慧, 王刚. 基于选区激光熔化的316L不锈钢的裂纹形成规律及机理[J]. 激光与光电子学进展, 2019, 56(10): 101401. Lu Pan, Chenglin Zhang, Liang Wang, Qihui Liu, Gang Wang. Crack Formation Law and Mechanism in Selective Laser Melting of 316L Stainless Steels[J]. Laser & Optoelectronics Progress, 2019, 56(10): 101401.