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0-75at％Co的Fe-Co合金,具有一系列的物理性质。运用新建立起来的固溶体综合理论,对此作出了较为满意的解释。原子态主要受最近邻〈F.N.N〉原子的影响。设i元素的原子状态以F.N.N中溶质原子个数j标记,则j特征原子态特征参量可表为Q_(ij);相应的状态浓度为c_(ij),它服从随机分布规律: c_(1j)=(j!/(J-j)!j!)(1-c)~(J-j+1)c~j c_(2j)=(j!/(J-j)!j!)(1-c)~(J-j)c~j合金相应的平均参量Q=∑c_(ij)Q_(ij)称之为特征参量相加定律。根据Fe-Co合金实验规律,并利用上述定律,确定了Fe,Co原子的特征态以及与之相应的特征参量;再代入同一公式,算出了无序合金α-c,m-c理论曲线。认为有序化过程中,各特征原子态的价电子结构不变,只是状态浓度发生变化,导致合金性质改变。利用有序度的概念,以及根据统计学观点,导出了Fe,Co特征原子态浓度计算式: c_(Fsj)=(J!/(J-j)!j!){(1/2)(c+η/2)(1-c+η/2)~(j-i)(c-η/2)~j+(1/2)(c-η/2)~(j+J)(1-c-η/2)~(J-j)} c_(Coj)=(J!/(J-j)!j!){(1/2)(1-c-η/2)(c-η/2)~j(1-c+η/2)~(J-j) +(1/2)(1-c+η/2)(c+η/2)~(J-j)}计算结果,最大有序度合金与无序合金的α-c曲线在38at％Co处相交,这与实验结果极为一致;有序合金的平均原子磁矩均比无序的大,亦与实验规律相吻合。将特征参量相加定律应用于合金平均结合能E_c计算中,对该合金比热特性作出了解释。计算结果表明,有序→无序转变,是结合能高〈即努阱深〉的态向势阱浅的态之转变过程,从而,出现正常比热峰;正常比热峰温度T_(NS)-C曲线与E_c-c理论曲线有类似的变化规律,说明T_(NS)高低应由有序合金结合能决定。当加热有序合金至一特定温度T_(as)时,发生部分有序→无序转变,这是势阱很深的态向势阱浅的态之转变过程,需要很高的激活能,出现正的反常峰;当加热无序合金时,情况将与上述相反,故将出现负的反常峰。此外,认为相互转变的两态间特征结合能差值愈小,则激活能愈小,转变量愈大,比热峰愈高。以此解释了反常比热峰温度T_(as)以及峰高与Co含量的关系。
0-75at% Co Fe-Co alloy, with a series of physical properties. Using the newly established theory of solid solution synthesis, a more satisfactory explanation has been made. The atomic states are mainly affected by the nearest neighbor atoms. Suppose the atomic state of element i is marked by the number j of solute atoms in FNN, then the characteristic parameter of j-state atomic states can be expressed as Q_ (ij); the corresponding state concentration is c_ (ij), which follows the rule of random distribution: c_ (1j ) = (j j / j j!) (1-c) ~ (J - j + 1) c ~ j c ~ (2j) = ~ (Jj) c ~ j alloy corresponding to the average of the corresponding parameters Q = Σc_ (ij) Q_ (ij) called the sum of the law of characteristic parameters. According to the experimental rule of Fe-Co alloy and using the above law, the characteristic states of Fe and Co atoms and the corresponding characteristic parameters were determined. Then the same formula was used to calculate the theoretical curve of α-c and m-c. It is considered that in the process of ordering, the valence electron structure of each characteristic atomic state remains the same, only the state concentration changes and the properties of the alloy change. Based on the concept of degree of order, and according to the statistical point of view, the formula for calculating the atomic concentration of Fe and Co is derived as follows: c_ (Fsj) = (Jj / Jj) η / 2 1 - c + η / 2 ~ ji c - η / 2 ~ j + 1/2 c - η / 2 ~ j + J 1 - c - η / 2) ~ (Jj)} c_ (Coj) = (J! / (Jj)! J!) {(1/2) (1-c-? / 2) (c-? / 2) -c + η / 2) ~ (Jj) + (1/2) (1-c + η / 2) (c + η / 2) ~ (Jj) The α-c curves intersect at 38at% Co, which is in good agreement with the experimental results. The average atomic magnetic moments of the ordered alloys are larger than those of the unordered ones and agree well with the experimental rules. The law of sum of characteristic parameters was applied to calculate the average binding energy E_c, and the specific heat characteristics of the alloy were explained. The results show that the transition from ordered to disorder is the transition from the shallow state with the high potential energy well, which leads to the normal specific heat peak. The normal specific heat peak temperature T_ (NS) -C curve and E_c-c theoretical curve have similar changes, indicating T_ (NS) level should be determined by the order of the alloy binding energy. Partial sequence → disorder transition occurs when the ordered alloy is heated to a specific temperature T_ (as), which is a transition from a shallow potential well to a shallow potential state, requiring a high activation energy to appear Positive anomalous peak; when heating the disordered alloy, the situation will be opposite to the above, so a negative anomalous peak will appear. In addition, the smaller the activation energy is, the larger the transition is, the higher the heat transfer peak is. In order to explain the anomalous specific heat peak temperature T_ (as) and the relationship between peak height and Co content.