In applications requiring large specific surface area, ultrathin walls fabricated by selective laser melting (SLM) have attracted wide attention. Understanding that the geometric characteristics of ultrathin walls are affected by process parameters is an important topic. To investigate the influence of SLM process parameters on geometric morphology, interlayer banding characteristics, and defects of the AlSi10Mg ultrathin walls, based on the normalized processing map, the multi-layers and single-track SLM tests under different energy density and interlayer cooling conditions were implemented. The ultrathin walls with the width between 100 μm and 450 μm were successfully fabricated in the range of single-track energy density between 5 and 30, and their geometric morphology and interlayer banding characteristics are not significantly affected by the interlayer cooling time. Except that the height of thin walls does not change significantly with the process parameters, the width, penetration depth, and cross-sectional area of molten pool all have a power function decreasing relationship with the scanning speed, and all have a linearly increasing relationship with the laser power and single-track energy density, respectively. The macroscopic banding distance decreases linearly with the increase of laser power and single-track energy density and decreases exponentially with the decrease of scanning speed. When the single-track energy density is about 5 and 25, it is easier to obtain a more uniform banding distance close to the standard preset layer thickness under high power (≥ 300 W) with lower scanning speed (≤ 0.589746 m/s). The process parameter combination of high laser power (≥ 300 W) and low energy density (E* = 5) contributes to obtaining ultrathin-walled structures with the narrowest width of about 100 μm. Within the range of single-track energy density of 10 to 20, the use of appropriate laser power and scanning speed can be expected to avoid “necking,” “keyhole pore,” and “cracking” defects. This work provides guidance for choosing reasonable SLM process parameters when fabricating ultrathin walls in practical engineering applications.

在需要大比表面积的应用中，通过选择性激光熔化 (SLM) 制造的超薄壁引起了广泛关注。了解超薄壁的几何特性受工艺参数的影响是一个重要的课题。为了研究 SLM 工艺参数对 AlSi10Mg 超薄壁的几何形貌、层间带状特征和缺陷的影响，基于标准化加工图，在不同能量密度和层间冷却条件下的多层和单道 SLM 测试是实施的。在5到30的单轨能量密度范围内成功制造了宽度在100μm和450μm之间的超薄壁，它们的几何形貌和层间带状特性不受层间冷却时间的显着影响。除薄壁高度随工艺参数变化不显着外，熔池的宽度、熔深深度、截面积均与扫描速度呈幂函数递减关系，均呈线性递增关系。分别为激光功率和单轨能量密度。宏观带距随着激光功率和单轨能量密度的增加呈线性减小，随着扫描速度的降低呈指数减小。当单轨能量密度约为 5 和 25 时，在高功率（≥ 300 W）和较低的扫描速度（≤ 0.589746 m/s）下，更容易获得接近标准预设层厚度的更均匀的条带距离。高激光功率（≥ 300 W）和低能量密度（E * = 5) 有助于获得最窄宽度约为 100 μm 的超薄壁结构。在10~20的单轨能量密度范围内，采用合适的激光功率和扫描速度，有望避免“颈缩”、“锁孔”、“开裂”等缺陷。这项工作为在实际工程应用中制造超薄壁时选择合理的 SLM 工艺参数提供了指导。