Optimization of Process Parameters for ESR Waspaloy Superalloy by Numerical Simulation

Abstract

A transient numerical simulation method is used to investigate the temperature field, velocity field, and solidified field of large-size Waspaloy superalloy during the electroslag remelting (ESR) process. The effects of melting rate, filling rate, and thickness of the slag layer on the molten pool shape and dendrite arm spacing evolution have been discussed. The temperature in the slag pool is high and relatively uniformly distributed, the temperature range is 1690–1830 K. The highest temperature of the melt pool appears in the center of the slag–metal interface, 1686 K. There are two pairs of circulating vortices in the slag pool, the side vortices are caused by the density difference caused by the buoyancy of the slag, the center vortices are the result of the combined action of electromagnetic force and the momentum of the falling metal droplets. The molten pool depth and dendrite arm spacing increase with the increase of melting rate, but the slag layer thickness and electrode filling rate have little effect on the molten pool morphology and dendrite arm spacing if the droplet effect is not taken into account. Considering the morphology and depth of the molten pool as well as the size and distribution uniformity of the dendrite arm spacing, it is appropriate to maintain the melting rate at 5.8 kg/min for the industrial scale ESR process with the ingot diameter of 580 mm.

Morphology Control of Metal Pool and Eutectic Carbides in Electroslag Remelted M2 HSS with an External Axial Static Magnetic Field

“…Nevertheless, with increasing ESR ingot diameter, the cooling capacity of the baseplate and mold progressively decreases. The cooling effect is insufficient, particularly in the ESR ingot's core, while the metal pool's depth increases [20,21]. Consequently, segregation and other metal metallurgical defects, as well as coarse ECs, tend to happen for large M2 HSS ESR ingots, a problem that has yet to be resolved in the industrial sector.…”