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采用分子动力学及镶嵌原子势模拟了包覆于Ni膜中的球形Ag粒子（含3055个原子）的熔化行为.发现Ag粒子与Ni膜可形成半共格界面,从而抑制了粒子的表面熔化,使其熔点升高至1330K,即相对Ag的平衡熔点（（1230±15）K）过热100K,而比相应的自由粒子的熔点约高290K.熔化以非均匀形核方式从有缺陷的局部界面处开始,并向粒子内部推进.采用热分析方法,在熔体激冷制备的Ag/Ni条带中观察到平均粒径为30nm的Ag粒子的过热度为70K.分析表明,用非均匀形核熔化理论可以很好地解释Ag粒子的过热行为.
The melting behavior of spherical Ag particles (containing 3055 atoms) coated in Ni film was simulated by molecular dynamics and inlaid atomic potential. It was found that the Ag particles and Ni film could form a semicontinuous interface and thus the surface melting of the particles was inhibited , Raising its melting point to 1330 K, ie overheating 100 K relative to the equilibrium melting point of Ag ((1230 ± 15) K), about 290 K higher than the melting point of the corresponding free particle. Melting occurs in a non-uniform nucleation fashion from the defective local The interface begins and advances to the interior of the particles.It is observed by thermal analysis that the superheat degree of Ag particles with the average particle size of 30nm is 70K in the melt quenched Ag / The theory of nucleation melting can explain the overheating behavior of Ag particles well.