Investigation of mechanical failure and abrasive wear behaviour of FeCoCrNiMo HEA cladding deposited on AISI 1050 steel by the TIG welding process

Abstract

High-entropy alloy (HEA) claddings are being actively considered to improve the mechanical and wear performance of engineering steels. Still, little is known about their mechanical failure and abrasive wear behaviour when deposited using cost-effective TIG welding. In this paper, the mechanical response, failure modes or wear behaviour of FeCoCrNiMo HEA claddings deposited on AISI 1050 steel are studied. Three HEA-cladded samples (specimens 1, 2 and 3) produced under varying TIG welding conditions were selected based on earlier work by the authors and carefully examined to gain insight into how changes in processing parameters affect mechanical and abrasive wear behaviour. Under varying TIG welding conditions, three clad samples with maximum, optimum and minimum hardness were prepared and tested using three-point bending tests, dry sand rubber wheel abrasion tests and detailed microstructural characterisation using SEM, EDS, XRD and 3D surface profilometry. The flexural strength of the optimised sample was a maximum of 1234.12 at 3.78% strain, and the volume loss was a minimum of 71.76 mm³ at 3.78% strain. The volume loss was the lowest, at 71.76 mm³, attributed to the homogeneous microstructure and a balanced, ductile hardness. Contrastingly, flexural strength and severe abrasive damage in the low-hardness sample were reduced by 31.9 per cent, due to the low interfacial bond strength and microstructural flaws. The fractographic and wear analysis showed that the common failure and wear mechanisms are crack initiation, crack deflection, micro-grooving, ploughing and delamination. The findings reveal that with adequate control of doublet TIG welding parameters, it is possible to produce FeCoCrNiMo HEA claddings with high mechanical integrity and wear resistance, suitable for challenging surface engineering tasks.