原子有序度对Zr55Al10Ni5Cu30非晶合金等温晶化过程的影响

通过改变母合金铸锭的重熔次数和熔体冷却速率获得3种具有不同原子有序度的Zr55Al10Ni5Cu30块体非晶合金,并采用差示扫描量热仪研究了原子有序度对该合金等温晶化过程的影响。结果表明,在等温晶化条件下,原子有序度的增加使Zr55Al10Ni5Cu30块体非晶合金孕育期明显减小;对晶化相的形核和长大机制几乎没有影响,均为形核速率随时间增加的扩散控制的三维长大;使Avrami指数出现一定程度的减小。

Effect of Atomic Order Degree on Isothermal Crystallization Process of Zr55Al10Ni5Cu30 Bulk Metallic Glass

The Zr55Al10Ni5Cu30 bulk metallic glasses with different atomic order degrees were obtained by changing the melting time of master alloy ingots and melt cooling rate, and the effect of atomic order degree on the crystallization process of Zr55Al10Ni5Cu30 bulk metallic glass was investigated by differential scanning calorimeter. The results show that the increase of atomic order degree of Zr55Al10Ni5Cu30 bulk metallic glass results in an obvious decrease of the incubation period but has no obvious effect on the mechanism of nucleation and growth of crystallization phase, which is diffusion-controlled three-dimensional growth and nucleation rate increasing with the time increasing. In addition, the increase of atomic order degree causes a decrease of Avrami exponent?to a certain extent.