Effect of the metastable b.c.c phase from undercooled Fe-30 at.% Co alloy on mechanical and magnetic properties

Abstract

Abstract The mechanical and magnetic properties of Fe-30 at.% Co alloy solidified at various undercoolings were measured to investigate the effect of the metastable b.c.c phase and the microstructure on alloy properties. The analysis indicates that alloy solidified at a low undercooling is brittle, thus leading to a lower toughness and tensile strength. With undercoolings below the critical undercooling temperature for the formation of the metastable ‘b.c.c’ phase from the melt, the toughness and strength of the alloy increased accordingly, which may be attributed to the impediment of the movement of dislocations and the reduced microsegregation. Undercooling of the alloy has little effect on the initial magnetization curve but considerably influences the kinetic magnetic loss, due to different microstructures, resulting in a significant change in the distribution of magnetic domains. The initial magnetization curve and the kinetic loss were analyzed from the viewpoint of the effect of the dendrite cores on the magnetic domains, which is of significance in dissipating the energy.