...
【24h】

Structural relaxation of Ti_(40)Zr_(25)Ni _8Cu_9Be_(18) bulk metallic glass

机译:Ti_(40)Zr_(25)Ni_8Cu_9Be_(18)大块金属玻璃的结构弛豫

获取原文
获取原文并翻译 | 示例
           

摘要

Ti_(40)Zr_(25)Ni_8Cu_9Be_(18) bulk metallic glass has a unique quenched-in nuclei/amorphous matrix structure. The crystallization of quenched-in nuclei, when the experimental isothermal annealing time is within its incubation time, may not disturb the enthalpy relaxation, which makes it have the accordingly common enthalpy relaxation behavior with amorphous materials. The alloy's annealing time dependence of recovery enthalpy follows a stretched exponential function with the mean relaxation time obeying an Arrhenius law. The equilibrium recovery enthalpy ΔHTeq, mean relaxation time τ and stretching exponent β are all dependent on the annealing temperature, and generally, a higher annealing temperature comes with a lower value of ΔH Teq, τ and a higher value of β. Two parameters, βg and τg, representing the stretching exponent and the mean structural relaxation time at the calorimetric glass transition temperature, respectively, are correlated with glass forming ability and thermal stability, respectively. For Ti_(40)Zr_(25)Ni _8Cu_9Be_(18) BMG, the high value of βg, which is much higher than 0.84 and approaches unity, reveals its good glass forming ability, while, on the other hand, the low value of τg indicates a worse thermal stability compared with typical BMGs.
机译:Ti_(40)Zr_(25)Ni_8Cu_9Be_(18)块状金属玻璃具有独特的淬火核/非晶基体结构。当实验等温退火时间在其孵育时间内时,淬灭核的结晶可能不会干扰焓弛豫,这使其具有与非晶态材料相应的常见焓弛豫行为。合金的恢复焓的退火时间依赖性遵循拉伸指数函数,平均弛豫时间服从阿伦尼乌斯定律。平衡恢复焓ΔHTeq,平均弛豫时间τ和拉伸指数β均取决于退火温度,通常,退火温度越高,ΔHTeq,τ的值越低,β的值越高。 βg和τg这两个参数分别代表在量热玻璃化转变温度下的拉伸指数和平均结构弛豫时间,分别与玻璃的形成能力和热稳定性相关。对于Ti_(40)Zr_(25)Ni _8Cu_9Be_(18)BMG,βg的高值远高于0.84,并且接近于1,表明其良好的玻璃形成能力,而另一方面,βg的值较低。 τg表示与典型BMG相比更差的热稳定性。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号