Multi performance optimization in machining of EN31‑535A99SS with interchangeable straight cemented tungsten carbide‑cobalt mixed (WC–Co) insert grade (CSTC—K20) using Taguchi coupled grey relational analysis

摘要

EN31-535A99 SS is an advanced and high carbon chromium-molybdenum alloy steel offering a high degree of compressivestrength and abrasion resistance. Best suitable for machined components subjected to abrasive wear, swaging dies,press tools, roller bearings which do not merit a more complex quality. However, its machining is one of the challengingfields in the metal cutting industries due to the high hardness which results in low productivity and high manufacturingcost. In this paper a new interchangeable two phases straight cemented tungsten carbide-cobalt mixed (WC–Co)insert grade (CSTC—K20) tool has been introduced to obtain the optimal turning parameters for the multi-performancecharacteristics in the turning process by Taguchi coupled grey relational analysis. The flank wear (Vbc) and surface finish(Ra) were considered as the performance characteristics while the cutting speed (V), feed rate (F) and depth of cut (D)as the controllable process parameters. Experiments were planned as per Taguchi L16 orthogonal array taking threeprocess parameters at four levels. The results revealed that the optimal parametric settings for multi-response becomescutting speed of 75 m/min, feed rate of 0.05 mm/tooth and depth of cut as 0.25 mm respectively. At this stage the surfaceroughness (R_a) reduced from 0.132 to 0.061 μm while tool flank wear (V_(bc)) reduced from 0.89 to 0.69 mm and the greyrelational grade enhanced up to 0.2867. The polynomial regression model presented higher R~2value as compared tolinear regression model. It is recommended that metal cutting industries could use these optimum approaches to reducethe material waste, manufacturing cost and increase productivity while machining of EN31-535A99 SS.