Al-Si gradient material with silicon content changing gradiently from 70% to 100% using 1050 aluminium alloy as the matrix was successfully prepared by laser cladding technology. Microstructure and properties of laser cladding layer were investigated. The results show that the most primary silicon with the largest size are distributed in the outer layer of the inner structure. From the surface of the cladding layer to the substrate,the volume fraction and size of the primary silicon decrease gradually,showing a gradient change. The morphology of silicon particles were changed from long-shaped to polyg-onal-shaped. As approaching the substrate,the particles tend to be disc-shaped. The different morphology of silicon particles is caused by the different temperature gradient and solidification speed,which is related to the size of molten pool and residence time. The hardness distribution of Al-Si gradient material is that the hardness of the outermost layer is higher. From the outside to the inside,the hardness decreases gradually,showing a gradient change.
aluminum alloylaser claddingaluminum-silicongradient material