Experimental investigation and optimization of the effects of SLM parameters on surface quality,geometric tolerances,microstructure and mechanical properties of CoCrMo dental alloys
Restricted accessResearch articleFirst published online May, 2026
Experimental investigation and optimization of the effects of SLM parameters on surface quality,geometric tolerances,microstructure and mechanical properties of CoCrMo dental alloys
Determining the optimum selective laser melting (SLM) parameters in the production of CoCrMo alloy, which is widely used in medical and dental applications due to its biocompatible structure, is of great importance both in terms of increasing part quality and ensuring production efficiency. Therefore, in this study, the effects of production parameters on surface quality, microstructure properties, mechanical behaviors, dimensional and geometric tolerances were investigated in the production of CoCrMo alloy using the SLM method. It is also aimed to simultaneously optimize the production parameters for the output parameters using Taguchi-based Gray Relational Analysis method. The results show that laser power and scanning speed have a decisive effect on all outputs. In particular, it was determined that high laser power and low scanning speed improve mechanical properties such as surface quality, hardness and density, but excessive volumetric energy density (VED) can increase geometric errors. The optimum manufacturing parameters for achieving the best values of all dimensional and geometric tolerances were determined to be a scanning distance of 0.055 mm, a laser power of 155 W and a scanning speed of 550 mm/s. A scanning distance of 0.055 mm, combined with a laser power of 185 W and a scanning speed of 450 mm/s, yielded the lowest measured surface roughness of 8.82 µm. Maximum relative density (99.468%) and hardness (36.9 HRC) values were obtained at the combination of 0.055 mm scanning distance, 185 W laser power and 450 mm/s scanning speed. It was observed that changes in VED have critical effects on both microstructure homogeneity and dimensional accuracy. As a result of the gray relationship analysis, the most suitable experimental conditions were determined as 0.055 mm scanning distance, 155 W laser power and 550 mm/s scanning speed.
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