合金元素对锆合金相变温度影响的价电子结构参数分析

Valence Electron Structure Parameter Analysis on Effect of Alloying Elements on Phase Transformation Temperature of Zirconium Alloys

摘要:

基于固体与分子经验电子理论（余氏电子理论），采用自洽键距差法计算了表征合金相性质的价电子结构参数，并利用该参数讨论了合金元素（Al、Sn、Ti、Hf、V、Mo、Nb、Cu、Fe、Cr、Ni、Pd、Re等）对锆合金相变温度的影响。结果表明：合金元素对锆合金相变温度的影响可以用α和β相的结合能之和（）与结合能之差（）来表征。溶入锆基体后结合能之和较小的Cr、Al、Sn、Fe、Cu、Ni、Ti等元素会抑制α→β相转变，提升相变温度；而溶入锆基体后结合能之和较大的Hf、V、Mo、Pd、Nb、Re等元素会促进α→β相转变，降低相变温度。在锆合金相变过程中，具有正结合能之差的元素（Al）将促进β→α相转变，提升相变温度；具有负结合能之差的元素（Cr、Sn、Fe、Cu、Ni、Ti、Hf、V、Mo、Pd、Nb、Re等）将抑制β→α相转变，降低相变温度。α相稳定元素（Al）和β相稳定元素（Mo、Nb、Re、V、Pd）可用和来解释，但是β相稳定元素（Cr、Fe、Cu、Ni、Ti）主要通过来解释；此外，α相稳定元素（Sn、Hf）可以用较小的来描述。

Abstract:

According to the self-consistent bond length difference (SCBLD) method based on the empirical electron theory of solids and molecules, namely the Yu Ruihuang electron theory, the valence electron structure parameters (VESPs) were calculated to characterize the properties of alloy phases, and to investigate the influence of alloying elements (Al, Sn, Ti, Hf, V, Mo, Nb, Cu, Fe, Cr, Ni, Pd, and Re) on the phase transformation temperature of zirconium alloys. The results show that the sum of cohesive energy () and the cohesive energy difference () of α and β phases can be used to characterize the effect of alloying elements on the phase transformation temperature of zirconium alloys. After dissolution into the zirconium matrix, the alloying elements (Cr, Al, Sn, Fe, Cu, Ni, and Ti) with smaller can inhibit the α→β phase transformation and increase the phase transformation temperature. However, the elements dissolved into the zirconium matrix, such as Hf, V, Mo, Pd, Nb, and Re, can promote the α→β phase transformation and reduce the phase transformation temperature because of the larger . In the phase transformation process of zirconium alloys, the element (Al) with positive accelerates the β→α phase transformation and increases the phase transformation temperature; the elements (Cr, Sn, Fe, Cu, Ni, Ti, Hf, V, Mo, Pd, Nb, and Re) with negative Δ′_C hinders the β→α phase transformation and decreases the phase transformation temperature. The α-stabilizers (Al) and the β-stabilizers (Mo, Nb, Re, V, Pd) can be explained by both the and , whereas the β-stabilizers (Cr, Fe, Cu, Ni, and Ti) can only be explained by . In addition, the α-stabilizers (Sn and Hf) can only be explained by .