A single-layer single-pass laser cladding test on 7075 aluminum alloy substrate with AlSi10Mg alloy pow-der as the cladding material is designed.The influence of laser power,scanning speed and powder feeding rate on the molding of the cladding layer is investigated,for explaining the phenomena of higher dilution rate and lower po-rosity.Results show that the width of the cladding layer increases while the height decreases with the laser power increasing.When the laser power increases to a certain degree,the height and width of the cladding layer increase significantly with the increase of the powder feeding rate.The scanning speed exerts a minimal effect on the width and height of the cladding layer at low power feeding rates.When the laser power is higher,the substrate and pow-der are fused sufficiently and fewer bubbles are generated.At the same time,a smaller powder feeding rate leads to a lower height of the cladding layer,which is more favorable for bubbles to escape from the melt pool,and the po-rosity of the cladding layer is reduced to 0.07%.Therefore,a higher laser power coupled with a lower powder feed-ing rate results in a diminished cladding layer height,signifying an elevated overall dilution rate.Consequently,the result provides guidelines for the reduction of aluminum alloy laser cladding porosity defects.
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