The evolution of structural and chemical heterogeneity during rapid solidification at gas atomization

[摘要] Gas atomization is a high-performance process for manufacturing superfine metal powders. Formation of the powder particles takes place primarily through the fragmentation of alloy melt flow with high-pressure inert gas, which leads to the formation of non-uniform sized micron-scale particles and subsequent their rapid solidification due to heat exchange with gas environment. The article presents results of computer modeling of crystallization process, simulation and experimental studies of the cellular-dendrite structure formation and microsegregation in different size particles. It presents results of adaptation of the approach for local nonequilibrium solidification to conditions of crystallization at gas atomization, detected border values of the particle size at which it is possible a manifestation of diffusionless crystallization.

[发布机构] Peter the Great St.-Petersburg Polytechnic University, Institute of Metallurgy, Mechanical Engineering and Transport, Saint-Petersburg; 195251, Russia^1

[效力级别] 计算机科学

[关键词] Cellular dendrites;Chemical heterogeneities;Crystallization process;Micro-segregation;Micron-scale particles;Non-equilibrium solidification;Powder particles;Results of computer modeling