Abstract: Specimens of 316 stainless steel were prepared by selective laser melting additive manufacturing technology under different laser powers. The crystallographic characteristics and hardness of the steel specimens were analyzed by means of OM, EBSD and Vickers hardness tester. The results show that with the decrease of laser power, the amount of precipitated phase decreases, but the input energy during manufacturing is low, the cooling rate of molten pool is high, the critical nucleation radius of dendrite is small, the nucleation rate and the number of nucleation are high during solidification, which is conducive to the grain refinement and the formation of equiaxial crystal, showing a high hardness value. The steel shows fiber texture with high degree of orientation under high laser power, while cube texture with low degree of orientation under low laser power. The main texture of the steel under laser power of 320 W is {110}<110> and {112}<111>, that under laser power of 290 W is {112}<110> and {112}<111>, and that under laser power of 260 W is {001}<110>.

Key words: additive manufacturing, 316 stainless steel, laser power, electron backscattered diffraction