Abstract: The process validation is carried out by the study on the H13 die steel formed by selective laser melting,the density and microstructure of the samples were analyzed.The result shows that too high and too low linear energy is not benefit to improve the density.The density of the samples formed by selectire laser melting could reach the highest value 94.27% with laser linear energy of 0.45J/mm,the laser power of 180W and the scanning speed of 400mm/s.Laser power is higher than scanning space on the influence of density during the forming process.The unreasonable combination of process parameters could lead to uneven internal microstructure,micro cracks and pores,these phenomena could reduce the density of the sample.

Key words: selective laser melting, H13 die steel, density, microstructure