Dry Sliding Friction and Wear Behavior of WC/WC-Ni Particles Laser Cladding Reinforced by Nano TiC on Mold Steel Surface

Abstract

To reduced the defect of the layer cladding reinforced by WC/WC-Ni Particles, and to attained the effective handicraft to strengthen the properties of the mold surface, using laser cladding technique , nano TiC reinforced WC/WC-Ni composite cladding were fabricated on the surface of H13 steel substrates. The cladding microhardness was measured with Victoria-hardness tester, the cross-section microstructure of the claddings was observed with optical microscope. The fabrication of the composite claddings was investigated. The friction and properties were examined under dry sliding conditions with a WTM—1E type ball-on-disc tester. The wear tracks were observed with a JSM-5610 type scanning microscope. The wear mechanisms were discussed as well. The results showed that, owing to the NanoTiC fine-crystalline strengthening and dispersive strengthening, the Nano TiC/WC/WC–Ni composite cladding was very compact and good blinding with the substrate after laser remelting, and then sub-micro-fracture and adhesion wear of WC cladding were reduced. During the friction process, Nano TiC particles had a significant influence on the Friction and wear behavior of laser cladding: The friction coefficient reduced and wear-resistance strengthened of composites with increasing proportion of TiC. The wear mass loss of the 20% TiC composite cladding reduced to about 1/3 of those with 5% TiC cladding.