Effects of Co and W on the microstructure and wear behavior of NiCrAlMoTiFeNbX equimolar multicomponent-clad layers

Abstract

In this study, we used the gas tungsten arc welding (GTAW) process for cladding NiCrAlMoTiFeNbCo and NiCrAlMoTiFeNbW multicomponent alloys onto the surface of AISI 1020 low-carbon steel. The microstructures and the sliding wear resistance of the cladding layers were characterized. The experimental results indicated that a multiple-carbide particle composed of (Nb,Ti)C with a TiC-rich core and NbC shell, was synthesized in situ in both multicomponent cladding layers. The eutectic phase of Fe0.875Mo0.125 with the body-centered cubic structure (BCC) was present in the NiCrAlMoTiFeNbCo cladding layer, and the reinforcing phase of Fe2W with the hexagonal-closest-packed (HCP) structure was in the NiCrAlMoTiFeNbCW cladding layer. Wear test results revealed that the wear performance of the multicomponent cladding layers can significantly improve the wear resistance of the AISI 1020 low-carbon steel. The wear resistance of the NiCrAlMoTiFeNbW cladding layer exceeded that of the other cladding layer. The improvement in the wear resistance of the NiCrAlMoTiFeNbW cladding layer was attributable to the high hardness of the cladding layer and the Fe2W reinforcement in the cladding layer. The wear test results confirmed that the cladding layer with higher ratios of hardness to Young's modulus for both the matrix and the strengthening phase exhibited better wear resistance.