中国激光, 2017, 44 (6): 0602006, 网络出版: 2017-06-08
半导体激光熔覆新型Co基合金耐擦伤性机制
Abrasion Resistance Mechanism of New Co-Based Alloy by Diode Laser Cladding
激光技术 激光熔覆 耐擦伤 Co基合金 微观组织 laser technique laser cladding abrasion resistance Co-based alloy microstructure
摘要
在316不锈钢表面进行激光熔覆Stellite 3、Stellite 21与新型Co基合金(Co-3)试验, 分析了熔覆层的显微组织及相成分, 研究了硬度分布和耐擦伤机理。试验结果表明, Co-3显微组织均匀、致密, 无裂纹与气孔, 其强化相主要为(Co,W)3C、Cr23C6、Cr7C3和Co3Mo。熔覆层的平均显微硬度约为624 HV0.2, 较基体提高3倍以上。Co-3的耐擦伤性能明显优于316基体的, 在载荷为0~150 N的情况下, 当划痕长度s≤3.3 mm时, 擦伤机理主要是塑性变形; 当划痕长度3.3 mm<s≤6.9 mm时, 擦伤机理主要是塑性变形引起的晶粒滑移与微裂纹形成; 当划痕长度s>6.9 mm时, 擦伤机理主要是裂纹扩展与塑性去除。
Abstract
Stellite 3, Stellite 21 and new Co-based alloy (Co-3) coatings are prepared on the 316 stainless steel surface by laser cladding. The microstructure and phase composition of the cladding layers are analysed and the microhardness distribution and abrasion resistance mechanism are also studied. The experimental results show that the microstructure of the Co-3 is homogeneous, compact, and without cracks and cavity, where the main phases consist of (Co,W)3C, Cr23C6, Cr7C3, and Co3Mo. The average microhardness of the cladding layer is about 624 HV0.2, which is more than 3 times higher than that of the substrate. The abrasion resistance performance of Co-3 is superior to that of the 316 substrate. Under the load of 0~150 N condition, when the scratching length s≤3.3 mm, the main scratch mechanism is plastic deformation; when the scratching length 3.3<s≤6.9 mm, the main scratch mechanism is grain sliding and crack formation caused by plastic deformation; when the scratching length s>6.9 mm, the main scratch mechanism is crack propagation and plastic removal.
吴国龙, 任方成, 姚建华, 毛伟, 李辉文. 半导体激光熔覆新型Co基合金耐擦伤性机制[J]. 中国激光, 2017, 44(6): 0602006. Wu Guolong, Ren Fangcheng, Yao Jianhua, Mao Wei, Li Huiwen. Abrasion Resistance Mechanism of New Co-Based Alloy by Diode Laser Cladding[J]. Chinese Journal of Lasers, 2017, 44(6): 0602006.