Thermodynamic modeling and experimental investigation of glass-forming magnesium alloys

开发一个包含所有可能的合金元素的可靠的Mg数据库是申请人的长期目标。这将通过计算热力学与DSC， XRD， SEM/EPMA和扩散偶技术的关键实验相结合来实现。事实证明，这减少了建立这种多组件数据库所需的时间和精力。目前的建议侧重于研究具有金属玻璃应用潜力的Mg三元体系。其中三种体系是Mg-Al-Y、Mg-Ni-Y和Mg-Cu-Y。镁基玻璃成形合金因其低密度、高强、优异的耐腐蚀性和高韧性而受到人们的特别关注。镁基金属玻璃具有较高的抗拉断裂强度，是传统镁基晶体合金最高强度的两倍以上。更重要的是，文献中提到，镁基合金具有生产最大体积金属玻璃的潜力。目前，国内外的研究主要集中在通过添加不同的合金元素来提高镁基合金的非晶形成能力。目前的建议旨在通过提供一个自一致的热力学数据库来促进这些努力，该数据库可用于识别具有最高玻璃形成能力的最有前途的mg合金成分。与目前的试错法不同，在拟议的研究中，有形成大块金属玻璃倾向的成分将使用该数据库进行识别。这可以通过识别表现出低洼液态表面的组合物来获得。值得注意的是，该策略将增加获得最适合大块金属玻璃应用的mg基合金的机会，而不是传统的经验试验和错误实验。此外，所提出的策略将能够预测玻璃形成能力的成分敏感性，这是基于原子尺寸分布的现有标准所不可能实现的。该项目将有利于加拿大的汽车和航空航天工业，并将为所有镁产品生产商提供新的机会。

Development of a reliable Mg database that contains all the possible alloying elements is the applicant's long term objective. This will be achieved through computational thermodynamics coupled with key experiments using DSC, XRD, SEM/EPMA and diffusion-couples techniques. This proved to reduce the time and effort necessary to establish such a multicomponent database. The current proposal focuses on investigating Mg ternary systems that have strong potential for metallic glass applications. Three of such systems are Mg-Al-Y, Mg-Ni-Y and Mg-Cu-Y. Mg-based glass-forming alloys have attracted special attention due to their low-density, high strength, excellent corrosion resistance, and high toughness. Mg-based metallic glasses exhibit high tensile fracture strength which is more than twice as high as the highest strength of conventional Mg-based crystalline alloys. More importantly, it is mentioned in the literature that Mg-based alloys have the potential to produce the largest bulk metallic glass. So far, the efforts worldwide are focussed on the improvement of the glass-forming ability of Mg-based alloys by additions of different alloying elements. The current proposal aims at contributing to these efforts by providing a self-consistent thermodynamic database that can be used to identify the most promising compositions for Mg-alloys that have the highest glass-forming ability. Unlike the current practice of trial and error method, in the proposed research, the compositions that have the tendency to form bulk metallic glasses will be identified using this database. This can be obtained through identifying the compositions that exhibit low lying liquidus surface. It is worth noting that this strategy will enhance the chance of obtaining the most suitable Mg-based alloys for bulk metallic glass applications instead of the traditional empirical trial and error experimentation. Further, the proposed strategy will enable predicting the composition sensitivity of the glass-forming ability which is not possible by the existing criteria that are based on atomic size distribution. This project will benefit Canadian automobile and aerospace industries and will provide new opportunities to all Mg products producers.