Year: 2024
Type: article
Abstract: This work investigates the influence of tungsten (W) on the microstructure of alloys in the system Fe–C–B–Cr. The main goal is to examine the effect of W-additions on the microstructure and especially the potential stabilization of primary or eutectic borides in alloys with the compositions of Fe–0.4C–1B–2.5Cr + W. Thermodynamic equilibrium and Scheil–Gulliver calculations are performed to identify microstructurally significant alloy-compositions which are also devoid of borocarbides at austenitizing temperature. Accordingly, laboratory melts are cast, samples are swaged, austenitized, quenched and tempered. Additionaly, a near-equilibrium state is created by a diffusion annealing step to validate the equilibrium calculation. The resulting microstructures are characterized by X-ray diffraction, scanning electron microscopy. It is shown that swaging can effectively convert the eutectic network into a powder-metallurgical-like spherical and isotropic hard phase dispersion without introducing microscopic or macroscopic defects. W-additions lead to the stabilization of eutectic FeWB and B-rich M23(B,C)6 carboborides as opposed to C-rich M23(C,B)6 formed in the quarternary Fe–C–B–Cr system. Thus, the chemical binding of B in M23(B,C)6 leads to a significant destabilization of the M2B-type borides FeWB and (Fe,Cr)2B. The results show that W-addition strongly influences the solidification reaction of Fe–Cr–C–B–W alloys and thus the present phases, even after diffusion annealing.
Institutions: Ruhr University Bochum, University of Wuppertal
Language: English
Subfield: General Materials Science
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,790
OpenAlex ID: W4405709242