Performance analysis of erosion resistant Mo2C reinforced WC-CoCr coating for pump impeller with Taguchi’s method

Abstract

Purpose This study aims to deal with development and performance analysis of high-velocity oxy-fuel (HVOF) thermally sprayed Mo2C-based WC-CoCr (tungsten carbine cobalt chrome) (Co-10% and Cr-4%) cermet coating deposited on the pump impeller steel 316 L. Design/methodology/approach In this work, a study was carried out by modifying the conventional WC-CoCr powder with a small addition of molybdenum carbide (Mo2C). Reinforcement was done by 1–4 wt.% addition of Mo2C feedstocks in WC-CoCr powder by using a jar ball mill process. The design of experiment was implemented for optimization of the percentage of Mo2C feedstock. L16 (4 × 4) orthogonal array was used to design the experiments for erosion output for the input parameters namely velocity, particle size, concentration and Mo2C proportion. Findings Results show that the Mo2C-based WC-CoCr coating provides better microhardness as compared to conventional WC-CoCr coating. The present study also reveals that the deposition of conventional WC-CoCr coating has improved the wear resistance of SS 316 L by 9.98%. However, the slurry erosion performance of conventional WC-CoCr coating was improved as 69.6% by the addition of 3% Mo2C. Practical implications WC-CoCr coatings are universally used for protecting the equipment and machinery from abrasion, erosion and corrosion. So, the 3% Mo2C-based WC-CoCr can be useful in power plants and various industries like mining, chemical, automobile, cementing and food processing industries. Originality/value A new HVOF coating has been developed by the addition of Mo2C feedstock in WC-CoCr powder (Co 10% and Cr 4%) and the percentage of Mo2C feedstock was optimized to improve the tribological behavior of WC-CoCr coating.