Effect of Print Method Based on SLM Technology on the Microstructure and Property of 316L Stainless Steel

Abstract

Samples of 316L stainless steel were fabricated by focus print and defocus print under the similar other process parameters with the scanning power, interval and speed of 450 W, 0.05 mm and 2000 mm/s, respectively. The microstructures and defects were observed by optical microscope and scanning electron microscope. Meanwhile, the density, hardness and tensile mechanical property were tested. The results show that only few micro-cracks exist in the microstructure of the focus-printed sample with density of 95.54%, however some holes do in the microstructure of the defocus-printed sample with density of 92.21%. The focus-printed sample exhibits the better comprehensive mechanical property, where the hardness, tensile strength, yield strength and elongation reach 206 HV, 645 MPa, 560 MPa and 45.0%, respectively. While they are 195 HV, 625 MPa, 545 MP and 38.0% for the defocus-printed sample, respectively.