Department of Materials Engineering and Convergence Technology, Gyeongsang National University, Jinju 52828, Republic of Korea.
3D Printing Materials Center, Korea Institute of Materials Science, Changwon 51508, Republic of Korea.
J Nanosci Nanotechnol. 2020 Nov 1;20(11):6807-6814. doi: 10.1166/jnn.2020.18792.
The correlation between microstructure and tensile properties of selective laser melting (SLM) processed STS 316L and Inconel 718 were investigated at various heights (top, middle and bottom) and planes and Columnar grains and dendrites were formed by directional growth during solidification. The average melt pool width and depth, and scan track width were similar in both specimens due to fixed processing parameters. SLM Inconel 718 has moderate tensile strength (1165 MPa) and tensile elongation (11.5%), whereas SLM STS 316L has outstanding tensile strength (656 MPa) and tensile elongation (75%) compared to other SLM processed STS 316L. Fine columnar diameter (0.5 m) and dense microstructures (porosity: 0.35%) in SLM STS 316L promoted the enhancement of tensile elongation by suitable processing condition. Fractographic analysis suggested that the lack of fusion pore with unmelted powder should be avoided to increase tensile properties by controlling processing parameters.
研究了选择性激光熔化（SLM）加工的 STS 316L 和 Inconel 718 的微观结构与拉伸性能之间的关系，分别在不同高度（顶部、中部和底部）和平面上进行了研究。在凝固过程中，通过定向生长形成柱状晶粒和树枝晶。由于固定的加工参数，两个试样的平均熔池宽度和深度以及扫描轨迹宽度相似。与其他 SLM 加工的 STS 316L 相比，SLM Inconel 718 具有中等的拉伸强度（1165MPa）和拉伸伸长率（11.5%），而 SLM STS 316L 具有出色的拉伸强度（656MPa）和拉伸伸长率（75%）。SLM STS 316L 中的细柱状直径（0.5μm）和密集的微观结构（孔隙率：0.35%）通过合适的加工条件促进了拉伸伸长率的提高。断口分析表明，通过控制加工参数，应避免因未熔粉末而产生的未熔合孔隙，从而提高拉伸性能。
