Investigation of the properties of Al-Sn alloy powders produced by gas atomisation

In this study, Al-20Sn-3Si, Al-15Sn-1Cu ve Al-15Sn-4Si-1,5Cu alloy powders were produced by using Dumlupınar University Gas Atomistion Unit and the properties of the alloy powders were investigated. An electrical resistance furnace was designed and produced in order to melt the alloys. Alloys were prepared in the curicible placed in the furnace by adding pure aluminium, tin, copper and Al-Si master alloys and the alloy powders were atomised by nitrogen gas. The produced powders were sieved by using 200 microns mesh and stored in the plastic bags. Powder size analysis, microstructure investigations, hardness measurements, and XRD analysis were made. Powder size of the alloys were between 42,40 and 60,30 microns. It is observed that, powder size was reduced by increasing the both atomisation pressure and gas/melt mass flow ratio. Powder surfaces are clean and mostly spherical in shape. Some satellite formation by colliding of the small powders to the big powders was observed. The big powders have cellular and dendritic solidification structure on the surface. Aluminium and tin phases were determined in all of the alloy powders.