Impact of atomization methods on aluminum alloy powder characteristics and 3D printing performance in laser directed energy deposition process

Abstract

A comparative study on the performance of gas atomized (GA) and rotating-disk atomized (RDA) aluminum alloy powders produced on industrial scale for laser directed energy deposition (L-DED) process was carried out. The powder characteristics, the printing process window, and the quality, microstructure, and mechanical properties of printed parts were taken into account for comparison and discussion. The results demonstrate that the RDA powder is superior to the GA powder in terms of sphericity, surface quality, internal defects, flowability, and apparent density, together with a larger printing process window during the L-DED parts fabrication. Besides, the resultant parts from the RDA powder have higher dimensional accuracy, lower internal defects, more uniform and finer microstructure, and more favorable mechanical properties than those from the GA powder.