Experimental investigation of process parameters on layer thickness and density in direct metal laser sintering: a response surface methodology approach

Direct metal laser sintering is an additive manufacturing method which allows manufacturing of complex parts without using dies in short time. In the present study, direct metal laser sintering of steel 316 powder has been studied. Response surface methodology has been used for the design and analysis of experiments. Nd:YAG laser with a maximum power of 75 W has used to sinter the powder. The effect of current, scan speed and laser frequency has been investigated on layer thickness and density of fabricated samples. In addition, by using multi response optimisation; appropriate setting to maximise layer thickness and density and also minimise applied energy was suggested. It can be seen that increases in current and frequency lead to increases in thickness and density of samples. Also increasing scan speed decreases layer thickness and density of samples.