Anisotropic Tensile and Compressive Strengths of Al-4wt.%Cu Alloy Powder: Part 2—Effect of Dendritic Arm Spacings

Abstract

This investigation focuses on the effects of the compaction directions (i.e., transversal and longitudinal) and microstructural arrays (inside the powder utilized to constitute the specimens) on the anisotropic strengths. The initial powders are obtained from the as-cast Al-4 wt.% Cu alloys solidified in two distinct cooling rates, i.e., ~0.5 and 2.5 °C/s. The powder particles are compacted by using 300, 400 and 600 MPa and sintered at 540 °C for 1 h. The compressive and tensile strengths are carried out and the anisotropic strengths are determined. It is found that transverse samples exhibit higher UCS (ultimate compressive strength) and UTS (ultimate tensile strength) than the longitudinal samples. It is also found that the powder compacted in the transversal direction and utilizing powder with finer dendritic arm spacing provides better UCS and UTS results. The novelty in the study concerns the fact that is evidenced in the role of the dendrite spacings concatenated with the compaction pressure and direction upon the mechanical behavior. It is concluded that depending on the compaction level intended or demanded mechanical behavior, the planning in the compaction direction is preprogrammed. Since recycled powder particles from conventional machining, drilling and turning can potentially be utilized to constitute parts and components, the environmentally friendly aspects are associated, and hazardous stages in a manufacturing process are substantially reduced or eliminated.