Oxidation Process of High-Alloy Steel Powders During Melt Atomization with Water

摘要

This study analyzes the influence of chemical composition and production conditions on the oxidation process of stainless-steel powder particles during melt atomization under high-pressure water. It also investigates the compositions of oxide films formed at the surface of particles during atomization according to the content of various components in the metal and the degree of influence of their protective properties on the oxidation process. Quantitative dependence of the oxygen content in the powder on the concentrations in the silicon or aluminum melt, which can form protective films, has been established.The effect of oxidation potential of the gas phase in the atomization chamber on the powder oxidation has been investigated. Powder oxidation has been established to do not exceed 0.2 when the oxygen content in the chamber atmosphere is less than 2. The dependence of oxygen content in the stainless- steel powder on the melt temperature, distance to the water level in the atomization chamber, and particle size is obtained. We determine that at optimal ratio of all parameters, oxygen content in the stainless-steel powder at 0.12–0.13 level can be obtained.