(1. 湖南文理學(xué)院 物理與電子科學(xué)系, 常德 415000;
2. 湖南大學(xué) 應(yīng)用物理系, 長沙 410082)
摘 要: 采用改進(jìn)分析型嵌入原子方法(MAEAM)， 對(duì)鈮、 鎢晶體的(001)面預(yù)熔和熔化過程進(jìn)行分子動(dòng)力學(xué)模擬。 通過計(jì)算不同溫度的原子位置、 層原子密度、 層結(jié)構(gòu)因子、 徑向分布函數(shù)等物理量， 研究(001)面的微觀結(jié)構(gòu)隨溫度的變化。 結(jié)果表明， (001)面在低于其完整晶體的熔化溫度出現(xiàn)預(yù)熔。 另外， 通過將該面預(yù)熔摩爾分?jǐn)?shù)對(duì)溫度進(jìn)行擬合發(fā)現(xiàn)， 可以近似地預(yù)測(cè)(001)面的預(yù)熔過程。
關(guān)鍵字: 鈮； 鎢； 熔化； 預(yù)熔； 改進(jìn)分析型嵌入原子法(MAEAM)； 分子動(dòng)力學(xué)(MD)
（1. Department of Physics and Electronics, Hunan University of Arts and Science, Changde 415000, China;
2. Department of Applied Physics, Hunan University, Changsha 410082, China）
Abstract: Using the modified analytic embedded-atom method (MAEAM), the molecular dynamics (MD) simulation was performed to study the premelting and melting behavior of (001) plane of niobium and tungsten. The physical properties including the atomic positions, the layer atomic density and the layer structure factor were calculated to disclose the relations between their microstructures and temperature. The results indicate that there are some quasiliquid layers on plane (001) at some temperature below the melting points of the prefect crystals. In addition, the premelting mole fraction of the surface of these two metals is fitted with the corresponding temperature to obtain a relational expression which is able to forecast the disordering progress of this surface.
Key words: niobium; tungsten; melting; premelting; modified analytic embedded-atom method (MAEAM); molecular dynamics (MD)
