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利用HREM和纳米束衍射技术证实了在Zr52.5Cu17.9Ni14.6Al10Ti5块体金属玻璃中存在1-3 nm大小亚稳F-Zr2Ni型和稳定四方晶系的Zr2Ni型结构的短程有序区.在此基础上发展了化学短程有序畴(CSRO)结构的概念,建立了计算CSRO摩尔分数和含CSRO熔体热力学状态函数的模型和方法.计算了Ni-Zr,Cu-Zr,Al-Zr,Al-Ni,Zr-Ni-Al和Zr-Ni-Cu合金系中各CSRO摩尔分数,并得到了这些合金的△GCSRO,△HCSRO和T△SCSRO等热力学参数,根据最大△GCSRO原则预测了上述合金系的最佳玻璃形成能力(GFA)的成分范围.这些计算结果与已有的Ni-Zr和Cu-Zr系非晶晶化激活能和Zr-Ni-Al系△Tx的实验数据相吻合,与Zr-Ni-Cu薄带的X射线衍射结果也符合得很好.基于CSRO模型的动力学计算表明,在最佳GFA成分范围内,Zr-Ni-Cu基合金的非晶形成临界冷却速度为～100K/s量级,符合目前制备块体非晶的实际冷却速度水平.
The short-range order region of Zr2Ni-type structure with 1-3 nm size metastable F-Zr2Ni and stable tetragonal Zr3.5Nu14.6Al10Ti5 bulk metallic glass was confirmed by HREM and nano-beam diffraction. Based on this, the concept of chemical short range ordered domains (CSROs) was developed and models and methods for calculating the CSRO molar fraction and the thermodynamic state function of the CSRO melt were established.Ni-Zr, Cu-Zr, Al-Zr, Al-Ni, Zr-Ni-Al and Zr-Ni-Cu alloys, and obtained the thermodynamic parameters △ GCSRO, △ HCSRO and T △ SCSRO of these alloys. According to the maximum △ GCSRO principle, Alloy system.The results of these calculations are consistent with the experimental data of the existing amorphous activation energies of Ni-Zr and Cu-Zr amorphous alloys and the △ Tx of Zr-Ni-Al alloys , Which is also in good agreement with the results of X-ray diffraction of Zr-Ni-Cu ribbon.The kinetic calculations based on the CSRO model show that the amorphous formation of Zr-Ni-Cu-based alloys under the optimal GFA composition forms critical cooling The speed is on the order of ~ 100K / s, which is in line with the actual cooling rate of the currently prepared bulk amorphous.