Economic Value of Using CrWN Films and the Contribution of Using Control Chart for Process Stability

Abstract

Abstract-This study investigates the optimization of direct current reactive co-sputter deposition process parameters to achieve multiple performance characteristics (roughness, roundness, and flank wear) in the CrWN thin films by the Grey-Taguchi method. In the confirmation runs, when using grey relational analysis, improvement of 17.045% was obtained in surface roughness, 20.833% in roundness, and 28.354% in flank wear, respectively. Furthermore, control charts tell us when special causes of variation are impacting the direct current reactive co-sputter deposition process and product characteristics are stable over time.Keywords-CrWN;co-sputter; grey-taguchi method; control charts I. INTRODUCTION Chromium tungsten nitride (CrWN) thin films were deposited onto tungsten carbide tools substrates, by direct current (DC) reactive magnetron co-sputter at room temperature. The effect and optimization of CrWN thin films deposition parameters (DC reactive magnetron co-sputter parameters: Cr power, W power, N2/(Ar+N2) flow-rate ratios and deposition time) on the structure, roundness and flank wear in the turning operations were studied. To strengthen wear resistance in conventional tool materials, sputtering techniques (physical vapour deposition, PVD) have recently found increasingly wider use in such coating applications [1][2][3]. The morphological and properties of tool are the results of the effect of deposition parameters on the thin films (sputter power, substrate temperature, substrate rotate speed, substrate-to-target distance, base pressure and process pressure) [4][5][6]. In this study, the co-sputter process parameters (Cr DC power, W DC power, N2/(Ar+N2) flowrate ratios, and deposition time) were controlled to insert hard metal chromium tungsten nitride (CrWN) onto tungsten carbide tools for dry machining .Taguchi experimental design is a powerful approach for increasing experimental