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The present study examines the effect of processing parameters on the abrasive wear behaviour of WC-10Co-4Cr TIG cladding. A response surface methodology-based central composite design was used to predict the optimized process parameters. Microstructure of the claddings processed at different parametric conditions was investigated through field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction analysis. A pin-on-disk tribometer was used to assess the tribological behaviour of the claddings. The surfaces of worn-out claddings revealed that the SiC abrading particles removed the material by yielding and ploughing of soft CoCr matrix. This results in the loosening and pull out of WC grains from CoCr matrix. However, the cladding obtained at optimum processing condition exhibited the better wear resistance as compared to the other claddings due to the presence of a large number of partially melted WC grains. Improvement in the hardness and fracture toughness also lead to the enhancement in abrasive wear resistance of optimized TIG cladding.

This study examines the micro-hardness and abrasive wear resistance of WC-CoCr cladding produced by tungsten inert gas (TIG) welding process. The effect of argon flow rate and standoff distance on the microstructure and properties of the cladding was also investigated. The morphology of WC-CoCr powder and its corresponding claddings was examined by FE- SEM analysis. The tribological behaviour of cladding was analysed by using pin-on-disc wear tribometer. High hardness and wear resistance were observed at higher values of standoff distance and argon flow rate. Wear in the cladding is mainly due to pull out of tungsten carbide particles along with plastic flow caused by yielding and extrusion of CoCr binder.

The present research examines the wear performance and cost of developing the micrometric and nano-metric WC-10Co-4Cr GTA claddings. The claddings were developed at optimized parametric conditions using a fully automatic GTA welding machine. The microstructure, elemental compositions and phases present in the deposited claddings were characterized by using FE-SEM, EDS and XRD, respectively. Micro-hardness of the micrometric and nano-metric claddings were evaluated with the help of a Vickers hardness tester. A pin-on-disc tribometer was used for conducting the abrasive wear test. The experimental results revealed that the abrasive wear in nano-metric cladding reduces by 30.72 % compared to micrometric cladding. The average microhardness of nano-metric cladding has improved by 25.51 % than micrometric cladding. Microstructural examination of worn-out claddings shows that the material was removed from the claddings due to the eruption of CoCr binder matrix along with the pull-out of WC grains, caused by the sliding motion of SiC particles. However, the cost of fabricating nano-metric cladding per unit area (Rs 0.163/mm2) was higher than the micrometric cladding (Rs 0.107/mm2) owing to the higher material cost of nano-WC-10Co-4Cr powder.