应用光学和电子显微镜及显微硬度计研究了铸造ＡｌＳｉ合金经激光表面熔融处理后的组织和性能。指出，组织分熔化区、过度区和基体三层。在熔化区中树枝状先共晶α相的平均宽度由原始组织的２０～４０μｍ细化到２～３μｍ，同时共晶组织也被大大细化。这些变化使显微硬度值由６７４提高至１０９～１１５ The microstructure and properties of the cast AlSi alloy after laser surface melting were studied by using optical and electron microscopy and microhardness tester. Pointed out that the organization sub-melting area, over the area and the substrate three. The average width of the dendritic eutectic α phase in the melting zone is refined from 20-40 μm to 2-3 μm in the original structure, and the eutectic structure is also greatly refined. These changes increase the microhardness value from 67.4 to 109-115