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采用激光闪光法确定Al86Gd6TM8(TM=Cu,Ni,Co,Fe,Mn,Cr,Ti,Zr,Mo,Ta)非晶合金在300~880 K时的热扩散系数、比热容和导热系数。利用差示扫描量热法确定合金放热和吸热反应温度。在氦气保护下采用传统的电弧熔炼法制备合金。所有合金的液相线过冷度高达80 K,这表明它们具有很好的非晶形成能力。在温度为350~550 K时,除Al86Cr8Gd6和Al86Zr8Gd6合金外,其它合金的比热容都符合Dulong–Petit定则。合金的热扩散系数和导热系数值都远低于纯铝的。同时发现在铝基体中添加14%(摩尔分数)的过渡元素(Gd+ТM)会大大降低晶态合金热扩散系数和导热系数的绝对值。合金组份间化学键强烈影响非晶Al86Gd6TM8合金的导热系数。
The thermal diffusivity, specific heat capacity and thermal conductivity of Al86Gd6TM8 (TM = Cu, Ni, Co, Fe, Mn, Cr, Ti, Zr, Mo and Ta) amorphous alloys at 300-880 K were determined by laser flash method. Determination of exothermic and endothermic reaction temperature by differential scanning calorimetry. The alloys were prepared by conventional arc melting under helium protection. The liquidus undercooling of all alloys is as high as 80 K, indicating that they have good amorphous formability. When the temperature is 350-550 K, the specific heat capacities of all the alloys except the Al86Cr8Gd6 and Al86Zr8Gd6 alloys are in accordance with the Dulong-Petit rule. Alloy thermal diffusivity and thermal conductivity values are far lower than the pure aluminum. It is also found that the addition of 14% (mol fraction) of transition element (Gd + ТM) to the aluminum matrix greatly reduces the absolute value of thermal diffusivity and thermal conductivity of the crystalline alloy. The chemical bonds between the alloy components strongly affect the thermal conductivity of amorphous Al86Gd6TM8 alloy.