The effect of preheating the build platform (process) on the microstructure/defect structure (structure) as well as the tensile and fatigue behaviour (property) of the laser beam powder bed fused (LB‐PBF) 316L stainless steel (SS) is investigated. Preheating the build platform to 150°C (P150) affects the thermal gradient and cooling rate resulting in the reduction of the volumetric defects (i.e., gas‐entrapped pores and lack of fusion (LoF)) as compared with the condition where the build platform is non‐preheated (NP). The ductility of P150 LB‐PBF 316L SS is improved as compared with the NP counterpart, resulting from the less volumetric defects as well as the change in the crystallographic orientation of the grains in P150 condition. In addition, preheating the build platform is found to enhance the fatigue resistance of LB‐PBF 316L SS specimens. This is associated with fewer and smaller volumetric defects in P150 specimens as compared with the NP ones.

中文翻译：

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通过预热构建平台来提高增材制造的金属材料的延展性和疲劳强度

研究了预热构建平台（过程）对激光束粉末床熔合（LB-PBF）316L不锈钢（SS）的微观结构/缺陷结构（结构）以及拉伸和疲劳行为（性能）的影响。 。与构建平台相比，将构建平台预热到150°C（P150）会影响热梯度和冷却速率，从而减少体积缺陷（即，气体包裹的孔洞和缺乏熔合（LoF））。未预热（NP）。与NP同类产品相比，P150 LB‐PBF 316L SS的延展性得到了改善，这是由于在P150条件下，较少的体积缺陷以及晶粒的结晶取向变化所致。此外，预热构建平台可以增强LB‐PBF 316L SS试样的疲劳强度。