中国激光, 2008, 35 (11): 1830, 网络出版: 2008-11-17
2Cr13不锈钢粉末激光直接堆积成形的组织与性能研究
Research on Microstructure and Properties of 2Cr13 Stainless Steel Parts Made by Laser Direct Metal Deposition
激光技术 快速成形 组织与性能 激光直接金属堆积 2Cr13不锈钢 laser technique rapid forming microstructure and property laser direct metal depositiob 2Cr13 stainless steel
摘要
为说明激光直接金属堆积(DMD)成形件的组织与性能特点,进行了2Cr13不锈钢粉末的直接成形实验研究。检测了不同工艺参数组合下单道熔覆、多道搭接和多层堆积的显微组织形貌,测试了2Cr13零件的硬度、耐磨损、拉伸和残余应力等性能。研究表明,单道熔覆的典型组织有柱状、胞状枝晶和等轴晶三种,其相互转化由温度梯度和凝固速率所决定; 由于粉末实时供给,搭接区与预置熔覆有很大不同; 多层堆积枝晶生长表现出一定倾斜性,受扫描方式影响较大; 不同工艺参数下,熔覆层平均硬度为300~550 HV0.2; 当组织为细化的树枝晶时,成形件耐磨损性能可比调质态2Cr13提高一倍以上; 成形件的平均抗拉强度比调质态2Cr13提高30%; 直薄壁墙零件不同位置处残余应力不同,但残余应力水平较低。
Abstract
Direct forming 2Cr13 parts were studied experimentally for explaining the performance of laser direct metal deposition (DMD) forming. The microstructure of single track cladding, multiple tracks overlapping cladding, and multi-layer deposition were observed. The mechanical properties of specimens, such as hardness, anti-abrasive, tensile and residual stress distribution, were tested. The experimental results showed that the typical patterns of single track had cellular dendritic, column dendritic, and equiaxed crystals. The patterns depended on the temperature gradient and the solidification rate of cladding. The overlapping zone of DMD specimen was different from that of powder preset cladding. The grains of multi-layer deposition specimen showed the characteristic of orientated growth which was influenced greatly by scanning path. Under different technological parameters, the average hardnesses of specimens changed from 300 HV0.2 to 550HV0.2. When the microstructure was thin dendritic crystal, the anti-abrasive property increased one time than that of 2Cr13 substrate which was quenched and tempered. The average tensile strength increased by 30%. The residual stresses were different at different positions, but all of them were small.
张伟, 姚建华, 彭伟, 董辰辉, 汤晓丹. 2Cr13不锈钢粉末激光直接堆积成形的组织与性能研究[J]. 中国激光, 2008, 35(11): 1830. Zhang Wei, Yao Jianhua, Peng Wei, Dong Chenhui, Tang Xiaodan. Research on Microstructure and Properties of 2Cr13 Stainless Steel Parts Made by Laser Direct Metal Deposition[J]. Chinese Journal of Lasers, 2008, 35(11): 1830.