Processing of Fe-Al-C-Ce alloys through air induction melting with flux cover (AIMFC) and electroslag remelting (ESR)

Abstract

The effect of process parameters on recovery of reactive element, cerium, during air induction melting with flux cover (AIMFC) and electroslag remelting (ESR) of Fe-10.5 wt% Al-0.8 wt% C-(0.1 and 0.3) wt% Ce alloys and also the effect of melting techniques on hot workability, structure and tensile properties (at room temperature and at 873 K) of Fe-10.5 wt% Al-0.8 wt% C-0.3 wt% Ce alloy have been investigated. Good recovery of cerium was obtained by AIMFC. While conventional fluxes were found to be unsatisfactory, modified flux containing CeO2 gave better recovery of cerium during ESR. The best recovery of cerium was achieved by using calcium as a deoxident during ESR. The combination of AIMFC and ESR yields a sound ingot of Fe-Al-C-Ce quaternary alloys free from gas and shrinkage porosity with very low oxygen, nitrogen and sulphur contents. Processing of AIMFC ingots through ESR has resulted in improved hot-workability. The ESR processed and hot-rolled alloy exhibited superior tensile elongation as compared to hot-rolled AIMFC alloy. This may be attributed to the comparatively sound, homogeneous and clean ingot, with a refined microstructure and fine uniform distribution of precipitates observed in hot-rolled ESR ingots.