Optimization of Surface Micro Hardness and Tool Life in Face Milling of AISI 52100 Alloy Steel using TGRA

AISI 52100 is high carbon chromium alloy steel, mostly used for making ball screws, roller bearings, and shafts because of its high strength, wear-resistance, and corrosion resistance properties. The mechanical properties of this material make its machining difficult due to the rise in tool wear and reaching a high-temperature during machining, which effects the micro hardness of the material. The tool needs to maintain its strength and hardness at elevated temperatures, resulting due to high cutting speed. Milling process parameters have effects on micro hardness and tool life during face milling of AISI 52100 alloy steel. The main aim of this study is to find the optimum process parameters for achieving a longer tool life and surface micro-hardness. Taguchi L18 orthogonal arrayis used with grey relational analysis (GRA). The process parameters used for studying are tool material-uncoated&coated carbide, cutting velocity, feed per tooth, and axial depth of cut. Cutting velocity is a highly influencing factor during machining. The optimum parameters with higher mean grey relational grade value are, coated tool, cuttingvelocity of 120 mm/min, feed rate of 0.120 mm per tooth, and 1.1 mm axial depth of cut.