Optimization of process parameters of direct metal laser sintering process using fuzzy-based desirability function approach

CL50WS material has been mainly used in tooling industries for making die, tool insert, mould or casting die. As the manufacturing of the CL50WS material parts from the DMLS machine differs from the conventional machining process, it is very essential to understand of DMLS behaviour and determine the proper optimal process parameter. Hence, the present study highlights the application of Box-Behnken method (BBD) of response surface methodology with fuzzy-based desirability function approach in order to optimize the multiple process parameters of direct metal laser sintering. The study also focused to investigate the effects of process parameters, viz. the laser power, scanning speed, layer thickness and hatch spacing, on the performance characteristics such as surface roughness, hardness and impact strength for the fabricated specimen using response surface plot. Fuzzy inference system has been applied in order to aggregate the aforementioned performance characteristics into a single objective response, i.e. multi-performance characteristic index. The optimum values of process parameters such as laser power 130 W, scan speed 550 mm/sec, layer thickness 0.03 mm and hatch spacing of 0.010 mm have been observed in the present study.