电磁铸造5182铝合金锭的组织与性能研究

采用电磁铸造技术铸造了易拉罐用5182变形铝合金，采用光学显微镜和扫描电镜分析了其显微组织，而且对其进行了均匀化处理和对比实验。结果表明，电磁铸造锭有更加良好的内部组织和优良的力学性能，电磁铸造试样的硬度大约是普通连续铸造试样的两倍，疲劳性能是普通连续铸造铸锭的3倍，电磁铸造铸锭还有良好的耐磨性，电磁铸造锭的优良性能得宜于电磁搅拌的作用使整个铸锭获得均匀细小的晶粒组织，电磁铸造技术是一种无模铸造技术，它依靠电磁力约束液体金属成型，液体金属不与铸模接触，铸锭表面光滑如镜；相反，普通连续铸造锭表面因存在振动痕和亚表面偏析等铸造缺陷，力学性能大大降低。

Microstructure and mechanical properties of aluminum alloy 5182 ingot cast by electromagnetic casting

In this paper the 5182 type aluminum alloys were cast by electomagnetic casting technology (EMC). The microstructure was analyzed by optical microscop and scanning electron microscop and compared with that of direct chill casting (DCC) , before and after the homogenizing treatment. Results show that the EMC ingots have better microstructure and excellent properties compared to the DCC ones. The hardness of EMC specimens increases twice to that of DCC ones and the fatigue life is three times higher as DCC ones in as-cast state, the EMC specimens also expresses a good wear resistance. All these results are indaced by the homogeneous microstructure over the entire cross section due to the electromagnetic stirring during the EMC process. Electromagnetic casting is a non-mold casting technology, which depends on the electromagnetic force to prevent the melt from touching the mold, so the ingot surface is very smooth. On the contrary, the surface imperfections, such as oscillation and subsurface segregation etc, found in DCC ingot, cause the mechanical properties drop largely.