Additive Layer Manufacturing (ALM) processes like Selective Laser Melting (SLM) enable the conception of complex designs with a high precision and equal or enhanced mechanical properties compared to Conventionally Manufactured (CM) structures. Nevertheless, this process, which consists in melting metallic powders layer by layer with a laser beam, greatly influences the microstructure and therefore the mechanical properties. While some studies have considered the effects of the thickness and/or the building direction of 316L Stainless Steel (SS) specimens produced by SLM on the quasi-static mechanical behavior, the strain rate effect for crash or impact applications on these two parameters has not been fully investigated. To complete the actual knowledge, the present work proposes to analyze the mechanical behavior of 316L SS tensile specimens produced by SLM with different build orientations (0°, 45° and 90°) and thicknesses (0.5, 0.75, 1 mm) and submitted to dynamic loadings at various strain rates up to ${10}^3{\text{ s}}^{-1}$. In addition, the microstructure and the fracture surfaces are analyzed to give a more detailed comprehension of the mechanical tests. It results that the SLM 316L SS achieves better Yield Stress (YS), similar Ultimate Tensile Stress (UTS) and equal or lower failure strain compared to the CM material. This is mainly a result of microstructure refinement. Anisotropy is observed at the macroscopic level with higher tensile stress and lower failure strain for horizontal specimens, which is explained by the different shapes, orientation and size of the grains at the microscopic level. The mechanical properties greatly decrease as the thickness reduces from 1 to 0.5 mm, by 14% for the YS and 16% for the UTS for a quasi-static loading. A minimum thickness of 0.75 mm is advised to at least recover the mechanical properties of the CM 316L SS. A positive strain rate sensitivity, higher than the CM material, is observed for all configurations, with the exception of 0.5 mm thickness. For strain rates ranging from to ${10}^{-3}$ to ${10}^3{\text{ s}}^{-1}$, there is an increase of 20% of the UTS. The material anisotropy is not affected by the strain rate sensitivity whereas the latter increases with the thickness.

与传统制造 (CM) 结构相比，选择性激光熔化 (SLM) 等增材层制造 (ALM) 工艺可实现具有高精度和同等或增强的机械性能的复杂设计概念。然而，这一过程包括用激光束逐层熔化金属粉末，极大地影响了微观结构，从而影响了机械性能。虽然一些研究已经考虑了 SLM 生产的 316L 不锈钢 (SS) 试样的厚度和/或构建方向对准静态力学行为的影响，但碰撞或冲击应用中的应变率对这两个参数的影响尚未进行了全面调查。完成实际知识，${10}^3{\text{ s}}^{-1}$. 此外，还分析了微观结构和断裂表面，以更详细地了解机械测试。结果表明，与 CM 材料相比，SLM 316L SS 获得了更好的屈服应力 (YS)、类似的极限拉伸应力 (UTS) 和相等或更低的失效应变。这主要是微观结构细化的结果。在宏观水平上观察到各向异性，水平试样具有较高的拉伸应力和较低的破坏应变，这可以通过微观水平上晶粒的不同形状、取向和尺寸来解释。随着厚度从 1 毫米减小到 0.5 毫米，机械性能大大降低，对于准静态载荷，YS 降低 14%，UTS 降低 16%。建议最小厚度为 0.75 毫米，以至少恢复 CM 316L SS 的机械性能。除 0.5 mm 厚度外，所有配置均观察到高于 CM 材料的正应变率灵敏度。对于应变率范围从${10}^{-3}$ 到 ${10}^3{\text{ s}}^{-1}$，UTS 增加了 20%。材料各向异性不受应变率敏感性的影响，而应变率敏感性随着厚度的增加而增加。