Patel Md Saad, Rahaman Ariful, Immanuel R Jose
School of Mechanical Engineering, Vellore Institute of Technology, Vellore, 632014, Tamil Nadu, India.
Advanced Materials Development and Characterization Group, Department of Mechanical Engineering, Indian Institute of Technology Bhilai, Kutelabhata, Durg, 491001, Chhattisgarh, India.
Sci Rep. 2025 Aug 20;15(1):30669. doi: 10.1038/s41598-025-16145-8.
Magnesium (Mg) alloys, owing to their lightweight, have gained substantial attention in industries such as aviation and automotive. Researchers are continuously working on different strategies to improve the performance of Mg alloys, among which alloying is of prime importance. However, care has to be taken so as to avoid over alloying of Mg as that would degrade the lightweight advantage of Mg. Addition of gadolinium (Gd) and yttrium (Y) to magnesium holds promise for improving mechanical performance, but a detailed comprehension of their synergetic effect on alloy's microstructure and deformation behaviour is crucial, which forms the basis of this study. Mg alloys with varying percentage of Gd and Y are developed in this study using gravity casting method. Microstructural assessment revealed a complex interplay of phases, including the presence of eutectic structures among other strengthening precipitates. Distribution and morphology of these microconstituents are studied in detail through electron microscopic techniques. Mechanical performance of the materials is assessed through tensile testing. Results indicated that the incorporation of Gd and Y influenced critical resolved shear stress (CRSS) values, affecting the activation of specific slip systems and twin systems. Post-deformation analysis preformed through fractography provided valuable information on the fracture modes and failure mechanisms, contributing to a comprehensive understanding of the alloy's reliability. Mechanisms leading to a typical microstructure and a resultant mechanical performance for Mg-Gd-Y alloy is discussed in detail.
镁（Mg）合金因其轻质特性，在航空和汽车等行业备受关注。研究人员不断探索不同策略以提升镁合金性能，其中合金化至关重要。然而，必须注意避免镁过度合金化，因为这会削弱镁的轻质优势。向镁中添加钆（Gd）和钇（Y）有望改善力学性能，但详细了解它们对合金微观结构和变形行为的协同作用至关重要，这构成了本研究的基础。本研究采用重力铸造法制备了不同钆和钇含量的镁合金。微观结构评估揭示了各相之间复杂的相互作用，包括共晶结构以及其他强化析出相的存在。通过电子显微镜技术详细研究了这些微观成分的分布和形态。通过拉伸试验评估材料的力学性能。结果表明，钆和钇的加入影响了临界分切应力（CRSS）值，进而影响了特定滑移系和孪晶系的激活。通过断口分析进行的变形后分析提供了有关断裂模式和失效机制的宝贵信息，有助于全面了解合金的可靠性。详细讨论了导致Mg-Gd-Y合金形成典型微观结构和最终力学性能的机制。
