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<正> 非晶态合金往往具有高强度和高屈服韧性等优异的力学性质,而且像结构弛豫和结晶化过程会对它产生明显的影响。只是以往的研究对象主要为金属-非金属型合金。在此,我们报道由前、后过渡金属所组成的金属-金属型非晶态合金的结构弛豫和结晶化效应。基于分析力学性质问题的复杂性,还把显微硬度的变化与差分比热、电阻率、超导临界温度、X射线小角散射和中子小角散射等测量结果作对照,并结合结构弛豫和结晶化动力学进行讨论。 一、实验 非晶态样品的制备方法和条件,以及对它作非晶态特性的检验,在文献[7]中已作报道。 显微硬度测量在LEITZ DURIMET 2上进行。测量时,应保证凹坑深度在带总厚度的三分之二以内。由于非晶带各个方向的冷却速率有所差异,往往导致其硬度值因测量所选择的面不同

The dependence of microhardness on the Co or Ni concentration has been measured for amorphous Zr_(100-x)M_x (M=Co, 22 x≤53.4; M=Ni, 24.1 x≤63.8) alloys. It is shown that the microhardness increases systematically upon increasing the concentration of Co or Ni. The effect of structural relaxation on the microhardness has been investigated for Zr_(78) Co_(22) and Zr_(75.9)Ni_(24.1). The microhardness exihibits a minimum and, then, increases slowly during isothermal annealing at 250℃. For isochronous annealing at differe nt temperature the microhardness increases very sharply when the crystallization temperature is approached. Complementary experimental results of DSC, resistivity, superconducting-critical-temperature and X-ray-diffraction measurements are used for an analysis of the phenomena occurring during structural relaxation and crystallization.