The lightweight magnesium–aluminum alloys are extensively used in automotive and aerospace industries due to their high-specific strength and low alloying cost, Grain refining via alloying and hot deformation is known as a viable technique for the enhancement of mechanical properties of these alloys. Accordingly, in the present work, grain size refinement and improvement of tensile properties of Mg-10Al magnesium alloy ingot via strontium addition (up to 1 wt%) and hot working (extrusion process) were studied. It was revealed that the addition of Sr up to 0.05 wt% leads to grain refinement of Mg-Al-Sr alloys with the resulting best strength-ductility combination. The as-cast alloys were quite brittle with total elongations well below 5% and their ultimate tensile strength (UTS) values were below 200 MPa, which was attributed to the coarse as-cast structure with a high content of brittle intergranular β-Mg₁₇Al₁₂ phase. It was also found that the aspect ratio of the Al₄Sr particles increases by increasing strontium content, which contributes to the deterioration of tensile properties at high strontium contents. Homogenization treatment at elevated temperatures led to the dissolution of the β phase, while the thermally stable Al₄Sr particles remained undissolved. The extruded alloys showed remarkably higher strength and ductility compared to the as-cast ingots, which were related to the remarkable grain refinement induced by the recrystallization processes during the hot extrusion process, the disappearance of the deleterious network of the intergranular eutectic constituent, and providing high solute Al content. As a result, UTS of ~ 406 MPa and total elongation of ~ 24% were obtained for the extruded alloy with 0.05 wt% Sr.

轻质的镁铝合金由于具有较高的比强度和较低的合金化成本而广泛用于汽车和航空航天工业。通过合金化和热变形进行晶粒细化是提高这些合金机械性能的可行技术。因此，在本工作中，研究了通过添加锶（至多1wt％）和热加工（挤压工艺）来细化晶粒尺寸和改善Mg-10Al镁合金铸锭的拉伸性能。揭示了添加至多0.05wt％的Sr导致Mg-Al-Sr合金的晶粒细化，从而得到最佳的强度-延展性组合。铸态合金非常脆，总延伸率远低于5％，极限抗拉强度（UTS）值低于200 MPa，₁₇ Al ₁₂相。还发现，通过增加锶含量，Al ₄ Sr颗粒的长径比增加，这有助于在高锶含量下降低拉伸性能。高温下的均质处理导致β相的溶解，而热稳定的Al ₄Sr颗粒保持不溶。与铸态铸锭相比，挤压合金具有更高的强度和延展性，这与热挤压过程中重结晶过程引起的晶粒细化，晶间共晶有害网络的消失和提供有关。高固溶铝含量。结果，对于具有0.05 wt％Sr的挤压合金，获得〜406 MPa的UTS和〜24％的总伸长率。