Cu-Zr-Ti块体非晶合金的形成及其力学性能

在Cu-Zr-Ti的三元合金系中发现了具有高非晶合金形成能力的Cu₆₀Zr_40-xTi_x(x=5%~27.5%,x为原子数分数)合金,采用铜模铸造法制备了块体非晶合金,其过冷液体温度区间为38~65?K.在该合金系中具有最高非晶形成能力的成分范围为Cu₆₀Zr_40-xTi_x(x=7.5%~12.5%),其非晶形成临界直径为5?mm,是Cu-Zr-Ti三元非晶合金中迄今为止非晶形成能力最高的合金.Cu₆₀Zr_40-xTix(x=7.5%~12.5%)块体非晶合金的杨氏模量、压缩断裂强度、压缩塑性应变和硬度分别为80~114?GPa,1?730~1?865?MPa,0.3%~1.5%和Hv 693~Hv 824,并随Ti含量的增加而提高.同时具有高非晶形成能力、高强度及显著塑性变形能力的铜基块体非晶合金的发现对非晶合金的基础研究和高性能结构材料的开发具有重要意义.

Formation and mechanical properties of Cu-Zr-Ti bulk glassy alloys

Cu-base bulk glassy alloys with high glass-forming ability were fabricated in Cu-Zr-Ti ternary system by copper mold casting. The critical diameter for glass formation was 5?mm for Cu₆₀Zr_40-xTi_x(x=7.5%, 10%, 125%) alloys, 4?mm for Cu₆₀Zr₂₅Ti₁₅ alloy and 3?mm for Cu₆₀Zr_40-xTi_x(x=15%, 17.5%, 22.5%, 25%) alloys. The glassy alloys exhibited distinct glass transition together with supercooled liquid region in the range of 38~65?K. The Young’s modulus, compressive fracture strength, plastic strain and Vickers hardness of the bulk glassy alloys are in the range of 80~114?GPa, 1?730~1?865?MPa, 0.3%~1.5% and Hv 693~Hv 824, respectively, and increase with increasing Ti content in the alloys. The finding of the Cu-based bulk glassy alloys with high glass-forming ability, high fracture strength and distinct plastic strain indicates a possibility for subsequent development of glassy alloys with new compositions which can be used for structural materials.