Designing Cu-Zr System Metallic Glass Based On The Law Of Modulus

Metallic glass is a new kind of amorphous alloy material, which has a long-range disordered atomic structure with a lot of free volume. The special structure leads to super high strength and elasticity of metallic glasses. On the other hand, the disordered atomic structure always generates global fragile fracture at the room temperature, hindering the broad application potential of the metallic glass. In this paper, we use elastic modulus law to design Cu Zr-based metallic glass system, for obtaining the excellent glass forming ability and good mechanical properties.Based on the relationship of elastic moduli and mechanical properties of metallic glass, one can design the composition of metallic glass system. Elastic moduli can be related to the atomic structure, thermodynamic stability, glass transition temperature, which factors also determine the relationship of glass forming ability and elasticity. The ratio of Young modulus and Volume modulus E/K can indicate the glass forming ability. So, obtaining bigger E/K will get excellent metallic glass with good glass forming ability. On the other hand, elastic properties have an intimate link with other mechanical properties. Previous research work has proved that the bigger Possion’s ratio, the more plastic deformation in metallic glass. Therefore, through the modulus law, optimizing the composition of glass forming alloy, it is possible to get both excellent glass forming ability and good mechanical properties.The results of designing metallic glass from modulus law, it is discovered that the binary alloy of Cu₅₀Zr₅₀ has best glass forming ability, and CuxZr100-x,（Cu Zr）100-xAlx systems with good mechanical properties. At first, we use modulus law to optimize binary Cu Zr alloy and obtain the composition with excellent glass forming ability and mechanical properties, and fabricate the samples of the alloy. Then, on the basis of binary alloy, we use modulus law to design the ternary metallic glass system for further improvement. At last, by four component addition, one can get the great increase of glass forming ability and mechanical properties.According to the reduced glass transition temperature Trg, the critical dimension tmax, and the critical cooling rate, we check the glass forming ability of the designed metallic glasses, and summarize the connection of modulus law and traditional empirical rule. Through the comprehensive mechanical performance test, the data of plasticity, strength, hardness, and elastic moduli are gotten, which can be helpful to value the designing process of modulus law in metallic glass system. The whole experimental results show that the law of modulus has good applicability to design metallic glass system with excellent glass forming ability and good mechanical properties.