Al基合金对304不锈钢腐蚀变化的研究

Researches on the change of Al alloy corrosion of 304 stainless steel

针对热镀锌内加热器的需求,研究制备陶瓷/Al基中间层/铁基合金层状结构复合材料.通过改变加热温度、保温时间测试304不锈钢在Al基合金中的腐蚀情况,来确定合适的连接工艺.通过金相显微镜、扫描电镜、能谱仪、X射线衍射仪等检测方法对腐蚀后的金属横断面进行分析.研究发现,Al基合金熔液与304不锈钢发生了反应,在850℃时反应剧烈,时间越长,腐蚀越严重.反应生成了致密的金属间化合物Fe_2Al_5相和块状的FeAl_3相.304不锈钢与Al基合金在750℃,保温30 min时结合最佳.

For the requirement of the heater in hot dip galvanized, one kind of composite material with ceramic/Al-based/ Fe-based alloy layer structure was investigated. Change the heat temperature and time, test the corrosion of stainless steel in Al alloy to find the best join process. The cross section of alloy after corrosion was investigated by OM, SEM, EDS and XRD. The results showed that Al-based alloy react with 304 stainless steel. The violent reaction will become at 850 ℃. The longer, the more serious corrosion. And finally a reaction layer which mainly consists of the intermetallic compounds Fe2Al5 and FeAl3 has been formed. The joining of 304 stainless steel to Al alloy was best at 750 ℃ for 30 min.