Optimization of process parameters in micro-plasma transferred arc deposition process for cobalt-based alloy

Abstract

This paper presents optimization of process parameters in micro-plasma transferred arc deposition (µ-PTAD) process for cobalt-based alloy. Pilot experiments were conducted to find feasible range of values of six important process parameters, followed by 27 main experiments varying three process parameters of µ-PTAD for single-layer single track deposition. Deposition height, deposition width and percentage of dilution were measured as well as predicted using the regression model by varying three process parameters as micro-plasma power, travel-speed of nozzle and deposition powder feed rate. Percentage errors were also computed between measured values and predicted values. Microstructural analysis, elemental composition analysis using energy dispersive X-ray spectroscopy (EDS and measurement of micro hardness values were also done for deposition materials. Results of microstructural and EDS analysis revealed that deposition of Cobalt-based alloy consist of two-phase matrix namely Cobalt-rich matrix and carbides (Cr23C6, Cr7C3 and W2C) -phase matrix. Micro-hardness analysis revealed that the values of micro-hardness increases with decrease in micro-plasma power. This above work proves that Cobalt-based alloy deposition using µ-PTAD process has a competence to extend an economical and suitable explanation for good quality deposition for various industrial applications.