火焰喷焊G302合金粉末涂层的组织和性能

Microstructure and mechanical properties of G302 alloy powder clad coating by flame spray

采用G302合金粉末在调质处理的27SiMn钢基体表面进行火焰喷焊,利用金相显微镜观察了喷焊层的截面组织;利用SEM能谱分析仪分析了喷焊层表面的成分分布;利用显微硬度计和磨粒磨损试验机分别分析测试了喷焊层的截面硬度和耐磨损性能,并与镀铬层进行对比。结果表明:喷焊涂层与基体结合良好,喷焊层合金成分均匀,组织为细小的枝状晶和等轴晶。性能与镀铬层相比,喷焊层的耐磨粒磨损性能约为镀铬涂层的1.1倍。

The coating on quenched and tempered 27SiMn steel was prepared by flame spray welding technique with G302 self-fluxing alloy powder. Cross-section microstructure of the coating was observed by OM. The surface composition distribution of the coating was observed by EDS. The cross-section hardness distribution and wear resistance of the flame spray welding coating and chromium plated coating were measured by mierohardness tester and abrasion tester respectively. The results show that the metallurgical bonding layer formed between the coating and substrate is good, and the composition distribution is homogeneous. The mierostructure is fine and consists of dendritic crystal and equiaxial crystals. Abrasive wear resistance of the coating is about 1.1 times of that of the chromium plated coating.