摘要
采用扫描电镜、能谱分析、X射线衍射仪以及显微硬度等表征手段,分析TiB_2-ZrB_2涂层与TiB_2-ZrB_2/Ni涂层电极点焊镀锌钢板时的失效过程。研究发现,无论是ZrB_2-TiB_2涂层还是ZrB_2-TiB_2/Ni涂层,在一定程度上均具有阻碍钢板镀层与点焊电极基体产生合金化反应的能力。ZrB_2-TiB_2、ZrB_2-TiB_2/Ni涂层电极失效过程存在些许不同,前者由于涂层与基体间结合力差,且涂层内塑性相相对较少,导致在点焊热和力的作用下,涂层逐渐脱落,点焊电极最终在合金化及塑性变形作用下发生失效。后者由于具有一定塑性,且涂层与基体结合力较好,点焊过程中涂层不会出现完全脱落现象。涂层作用一直持续至电极失效,电极失效形式主要表现为塑性变形。
Scanning electron microscopy,energy dispersive spectroscopy,X-ray diffractometer and microhardness are used to analyze the degradation process of TiB2-ZrB2 coated electrode and TiBz-ZrBJNi coated electrode in spot welding of galvanized steel sheet. The results show that both ZrB2-TiB2 coating and ZrB2-TiB2/Ni coating have a certain degree of ability to hinder the alloying reaction between the cladding of steel plate and spot welding electrode substrate. The degradation processes of ZrB2-TiB2,ZrB2-TiB2/Ni coating electrodes are a little different. For the former,due to its poor bonding force between the coating and substrate,and relatively small plastic phase in the coating,the coating gradually falls off under the action of heat stress of spot welding,the spot welding electrode degradation finally occurs under the influence of alloying and plastic deformation. For the latter,due to its certain plasticity and good bonding force between the coating and substrate,the coating partly falls off in the process of spot welding. The effect of coating lasts until the electrode degradation and the degradation mode is mainly plastic deformation.
出处
《电焊机》
2017年第6期7-13,共7页
Electric Welding Machine
基金
国家自然科学基金(51375150)
博士科研启动基金(BSQD2015015)
绿色轻质材料与加工湖北工业大学协同创新中心开放基金(201611A07)
