Influence of laser power and scan speed on the microstructure and properties of GH4169 alloy prepared by selective laser melting

Abstract

In this work, GH4169 alloy prepared by selective laser melting (SLM) used the domestic SLM equipment, the effects of different laser power and scan speed on the density, microstructure and mechanical properties of GH4169 alloy were systematically studied. The results showed that the density and hardness of SLM products increased with the increase of laser power. When the laser power was 300 W, The microstructure of alloy was uniform, and the density and Vickers hardness of alloy were 8.19 g/cm³ and 345.6 HV, respectively. The laser transferred energy decreased with the increase of scan speed, which cause more holes and cracks in the alloy. The smaller scan speed, the larger width and smaller height of ichthyoid microstructure. When the scan speed was lower than 1400 mm/s, the L and H were about 110 μm and 50 μm respectively, and the solidified structure was uniform and dense.