The use of aluminum (Al) alloys for additive manufacturing (AM) has recently gained significant attention, specifically in the aerospace industry. This has been resulting in introducing new high strength Al alloys that are more compatible with the AM processes. However, it is critical to investigate the structural integrity of these newly developed Al alloys prior to being deployed in safety-critical load-bearing applications. This study investigates and compares the microstructure, porosity, and fatigue behavior of five different contemporary Al alloys fabricated via a laser beam powder bed fusion (LB-PBF) AM process. Vertically and horizontally built specimens out of AlSi10Mg, Scalmalloy, QuesTek Al, AD1, and AlF357 are fabricated to capture any effects of build orientation on the structural integrity of these alloys. Despite the variation in micro-/defect-structure of vertical and horizontal specimens, no significant build orientation dependency is observed on fatigue behavior of AlSi10Mg, Scalmalloy, and AD1 alloys. However, AlF357 and QuesTek Al show some anisotropic behavior in the high cycle fatigue regime. Among the LB-PBF Al alloys investigated, Scalmalloy and AD1 are found to have the highest fatigue resistance ascribed to their superfine microstructure.

铝 (Al) 合金在增材制造 (AM) 中的使用最近受到了广泛关注，特别是在航空航天工业中。这导致引入了与增材制造工艺更兼容的新型高强度铝合金。然而，在将这些新开发的铝合金用于安全关键的承重应用之前，调查其结构完整性至关重要。本研究调查并比较了通过激光束粉末床融合 (LB-PBF) AM 工艺制造的五种不同现代铝合金的微观结构、孔隙率和疲劳行为。由 AlSi10Mg、Scalmalloy、QuesTek Al、AD1 和 AlF357 制成的垂直和水平构建的试样用于捕捉构建方向对这些合金结构完整性的任何影响。尽管垂直和水平试样的微观/缺陷结构存在差异，但没有观察到明显的构建方向依赖于 AlSi10Mg、Scalmalloy 和 AD1 合金的疲劳行为。然而，AlF357 和 QuesTek Al 在高周疲劳状态下表现出一些各向异性行为。在所研究的 LB-PBF 铝合金中，发现 Scalmalloy 和 AD1 具有最高的抗疲劳性，这归因于它们的超细微观结构。