摘要
在灰铸铁表面用专用的合金焊丝进行堆焊试验。借助光学显微镜、扫瞄电子显微镜、能谱仪对堆焊层及热影响区显微组织进行观察与分析,得知堆焊层显微组织特征是分布在FeNi基体上的树枝状V8C7,热影响区组织为细的莱氏体,多层堆焊层与基体结合良好。通过显微硬度计测试了堆一层的显微硬度为HV900-1200,堆两层的为HV700-900,说明堆焊层数增加,结合牢固,裂纹倾向减少。
A laser overlaying welding experiment was performed on the surface of gray cast iron by using the special alloy wire. The microstructure of the overlaying layer and heat-affected zone was observed and analyzed by optical microscope, SEM and XRD. The results showed that the dendritic V8C7 distributed on FeNi matrix in laser overlaying layer, and thin ledeburite distributed in the heat-affected zone. The overlaying multi-layer had excellent metallurgical bonding with the matrix. The microhardness of one surfacing layer was HV900-1200 and that of two surfacing layers was HV 700-900. From the research, we can concluded that with the increasing of surfacing layer, the bonding strength was much better, and the trend of cracking was reduced.
出处
《科技通报》
2005年第4期448-452,共5页
Bulletin of Science and Technology
关键词
灰铸铁
激光堆焊
显微组织
性能
裂纹
gray cast iron
laser overlaying welding
microstructure
properties
cracking
