冷却速率对ZrCuAlNiNb块体金属玻璃室温塑性及断裂强度的影响

Effect of coolingrate on compressive plasticityof ZrCuAlNiNb bulk metallic glasses

通过水冷铜模吸铸法制备出了不同直径的Zr57Nb5Cu15.4Ni12.6Al10金属玻璃棒材,研究了冷却速率对该金属玻璃室温塑性及断裂强度的影响。结果表明,冷却速率从63K/s逐步增加至1000K/s,该金属玻璃室温压缩塑性却从0.41%显著增加到31.43%,其断裂强度也随之从1706MPa显著提高至2556MPa,两者均表现出对冷却速率有强烈依赖关系。差热分析揭示这种依赖关系归因于随着冷却速率的提高,该金属玻璃中自由体积显著增加。

The influence of cooling rate on the plasticity and fracture strength of Zr57 Nb5 Cu15.4 Ni12.6 Al10 was studied by using samples with the diameters of 2 mm,5 mm,and 8 mm which were prepared by the water-cooled copper mould.The experimental results indicated that the cooling rate while only gradually increased from 63 K/s to1000 K/s,the the room temperature compressive plasticity,jumped from 0.41%to 31.43%,the fracture strength has been significantly higher from 1706 MPa to 2556 MPa,both show a strong dependence on the cooling rate.The differential thermal analysis reveals that the dependence is attributed to the significant increase in the free volume of the Zr57 Nb5 Cu15.4 Ni12.6 Al10 as the cooling rate increases.