Evaluation of injection molded gas and water atomized 316l stainless steel powder properties

Abstract

This research investigates the features crucial to injection molding via the rheological behavior, injection molding, debinding, and sintering process of water and gas atomised 316L stainless steel powder utilizing a newly developed locally based binder system containing palm stearin. The critical powder loading for injection molding was 65vol% for gas atomisation and 62vol% for water atomisation. Due to the minimal interparticle friction and high packing density, the gas-atomised powder proved easier to shape. In contrast, the water-atomised powder has a high viscosity of the injection molding feedstock, a high interparticle friction, and a low packing density, all of which impede injection molding. The debinding of the binder was accomplished utilizing solvent and thermal methods. After debinding, samples were sintered in a high-temperature vacuum furnace at 1360 degrees Celsius. Results reveal that water-atomised powder can be sintered to 95% of its theoretical density, whereas gas-atomised powder can be sintered to near full density.