为了更好地计算纳米材料晶格畸变能的尺寸效应,基于原子键能与表面热力学理论,提出了一个热力学模型.研究发现,随着晶粒尺寸的变小,纳米材料的晶格畸变能是不断增大的,且在20 nm以下时,这种变化将变得十分显著.随后,对该模型进行了讨论与验证,结果表明:模型给出的结果与实验数据接近,能较好地解释晶格畸变的尺寸效应.
To better calculate the size effect of the lattice distortion energy of nanoparticle, based on the surface thermodynamics and atomic bond energy, a classic thermodynamic model is proposed. It is found that the lattice distortion energy of nanoparticle increases with the decrease of the grain size. Then, according to this model, the lattice constants, lattice distortion energy and grain size, and density of the grain are analyzed. Results show that the numerical results agree well with the experimental data.