超高强钴基块体非晶合金的组成设计

块体非晶合金是一类具有高强度、高硬度和大弹性极限的无序金属材料,其优异的力学性能是目前先进金属材料领域研究热点之一,如何提高材料的强度是材料研究领域永恒的主题。系统地总结了已知具有超高强度的一类块体非晶合金材料——钴基块体非晶合金的成分、热学稳定性及力学性能;同时研究了不同非晶合金的断裂强度与其弹性常数、硬度和特征温度的关联。研究结果表明：在非晶合金体系中杨氏模量、维氏硬度、玻璃转变温度与断裂强度之间都存在较好的线性变化关系。基于以上结果,本课题组提出了超高强钴基块体非晶合金的组成设计方法,即选取具有强共价键特性的非金属元素和高模量、高熔点过渡金属元素与钴元素进行组合。

Alloy Design of Ultrahigh Strength Co-Based Bulk M etallic Glasses

Bulk metallic glasses （ BMGs） are a kind of disorder metal materials with high strength, high hardness and large elastic limit.The development of these materials is one of the most attractive topics for advanced metal materials . How to improve the strength of materials is an eternal topic for material scientists .In this paper, we summarized alloy compositions, thermal stability and mechanical properties of typical Co-based BMGs as the best candidates to design ultra-high strength BMGs due to their excellent mechanical properties .Possible relationships between the mechanical properties and other physical parameters, like elastic moduli, hardness and characteristic temperature in various kinds of BMG sys-tems are investigated.The Young’ s modulus, the Vickers hardness or the glass transition temperature shows a linear de-pendence on the fracture strength.According to the above results, the design method of element constitution for the ultra-strong Co-based BMGs was presented.The metalloid element（s） with the characteristics of strong covalent bond and the transition metal element（ s） with high elastic moduli and high melting temperature should be adopted to be great beneficial for the development of ultrahigh strength Co-based BMGs.