(1. 江蘇理工學(xué)院 江蘇省先進(jìn)材料設(shè)計(jì)與增材制造重點(diǎn)實(shí)驗(yàn)室，常州 213001；
2. 中南大學(xué) 材料科學(xué)與工程學(xué)院，長(zhǎng)沙 410083)
摘 要: 基于Miedema模型及其相關(guān)物性參數(shù)研究合金元素在Mo中的活度和溶解度，并將預(yù)測(cè)結(jié)果與第一性原理計(jì)算及其他經(jīng)驗(yàn)方法的結(jié)果進(jìn)行比較。結(jié)果表明：合金元素在Mo中的活度隨著溫度及合金元素濃度的增加而增大；在相同濃度條件下，主族元素Ge、Al和Si在Mo中的活度較小，過(guò)渡族元素Ti、Hf、Nb、Zr和Re等活度較大，后者往往成為鉬基合金的主要合金化元素。溶解度研究表明，合金元素在Mo中的溶解度受到原子尺寸因素、電子密度因素和電負(fù)性因素的影響，而合金元素在Mo中的溶解熱則是后兩個(gè)因素的綜合反映。以溶解熱和原子尺寸參數(shù)為橫縱坐標(biāo)建立Miedema-Alonso圖發(fā)現(xiàn)，其與Mo原子尺寸差異小于15%，且在Mo中溶解熱在-20~20 kJ/mol之間的合金元素有望在Mo中獲得較大的溶解度。
關(guān)鍵字: 鉬；活度；溶解度；Miedema模型；第一性原理
（1. Jiangsu Key Laboratory of Advanced Materials Design and Additive Manufacturing, Jiangsu University of Technology, Changzhou 213001, China;
2. School of Materials Science and Engineering, Central South University, Changsha 410083, China）
Abstract:The activity and solubility of alloying elements in Mo were investigated by using Miedema’s model and its related physical parameters, and these results were compared with the results predicted by the first-principle calculations and other’s empirical approach. These results show that the activity of alloying elements in Mo increases with the increasing temperature and alloying concentration. Under the same concentrations, the activities of main group elements Ge, Al and Si in Mo are small, and the activities of transition elements Ti, Hf, Nb, Zr, and Re are relatively large, which the latter should be chosen as the main alloying elements of Mo-based alloys. The solubility results also point out that the solubility of alloying element in Mo is influenced by atomic size factor, electron density factor, and electronegativity factor. And the solution heat of alloying elements in Mo is a comprehensive reflection of the last two factors. Furthermore, Miedema-Alonso plot was established by using the solution heat of alloying elements in Mo and atomic size parameters as the horizontal and vertical coordinates, respectively. It is found that the alloying element, which its atomic difference from Mo is smaller than 15% and its solution heat in Mo lies in the rang from -20 to 20 kJ/mol always has large respectively solubility limit in Mo.
Key words: Mo; activity; solubility; Miedema’s model; first-principle
