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In order to produce high-quality SAC305 alloy spherical powder, we studyed the effects of operating parameters: rotating speed, melt feed rate, shape and size of atomizer, and oxygen content in the atomizer chamber on the performance to produce Sn-3.0Ag-0.5Cu powder by rotary centrifugal atomization. It was evidenced from the experimental results that the median size of the atomized powders became smaller with increasing rotating speed（6000-60000rpm）, decreasing melt feed rate(30-60kg/h the ), and use of larger atomizer（30-50mm）, the experiment value of n is 1.65，the CFD value of n is 1.65. A cup shaped atomizer was able to give approx. 8% finer powder compared to that from a flat-disk shaped one. SEM micrographs revealed that the oxygen content of the atomization chamber decreased, the powder sphericity factor approached 1. When the oxygen content in the atomization chamber was less than 400 ppm, the oxygen content on the powder surface was less than 100 ppm. The surface quality is the best when the superheat of the atomization chamber and the melt is 230℃, the atomization parameters control the particle size and sphericity of the powder. SAC305 powder particle size and sphericity are mainly controlled by the process, and the powder surface quality is related to the cooling efficiency and collection technology.