This study aims to further the understanding of support structures and the likely impacts on maraging steel MS1 parts fabricated by selective laser melting (SLM) at 45°, 60° and 75° building angles.,Two groups of samples, one group with support structures and the other group without support structures, were designed with the same specifications and printed under the same conditions by SLM at 45°, 60° and 75° building angles. Differences in dimensional accuracy, surface roughness, Vickers microhardness, residual stress and microstructure were compared between groups.,The results showed that with support structures, more accurate dimension and slightly higher Vickers microhardness could be obtained. Larger compressive stress dominated and was more uniformly distributed on the supporting surface. Without support structures, the dimension became more precise as the building angle increased and alternating compressive and tensile stress was unevenly distributed on the supporting surface. In addition, the surface roughness of the outer surface decreased with the increase of the built angle, regardless of the support structures. Furthermore, whether the building angle was 45°, 60° or 75°, the observed microstructures revealed that the support structures altered the orientation of the molten pool and the direction of grain growth.,This paper studies the influence of support structures on the workpieces printed at different building angles. Support structures affect the residual stress distribution, heat dissipation rate and microstructure of the parts, and thus affecting the printing quality. Therefore, it is necessary to balance the support strategy and printing quality to better apply or design the support structures in SLM.

中文翻译：

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支撑结构对不同构建角度激光选区熔化马氏体时效钢 MS1 零件的影响

本研究旨在进一步了解支撑结构及其对选择性激光熔化（SLM）在 45°、60° 和 75° 构建角度制造的马氏体时效钢 MS1 零件的可能影响。,两组样品，一组带有支撑结构另一组没有支撑结构，采用相同规格设计，并在相同条件下由 SLM 以 45°、60° 和 75° 构建角度打印。比较各组在尺寸精度、表面粗糙度、维氏显微硬度、残余应力和显微组织方面的差异。结果表明，采用支撑结构可以获得更精确的尺寸和稍高的维氏显微硬度。较大的压应力占主导地位，并且在支撑面上分布更均匀。没有支撑结构，随着建筑角度的增加和交替的压缩和拉伸应力在支撑面上的分布不均匀，尺寸变得更加精确。此外，无论支撑结构如何，外表面的表面粗糙度都随着建造角度的增加而降低。此外,无论构建角度是45°、60°还是75°,观察到的微观结构表明支撑结构改变了熔池的取向和晶粒生长的方向。,本文研究了支撑结构对工件的影响打印在不同的建筑角度。支撑结构影响零件的残余应力分布、散热率和微观结构，进而影响打印质量。所以，