基于微观结构计算晶体宏观弹性应变场

基于晶体的微观结构提出了一种计算晶体宏观弹性应变场的方法,将该方法应用于金属晶体Fe，得到的应变场与连续介质理论预测结果吻合地很好，从而证明了该方法的准确性.以该方法为基础，进一步考虑无限小应变与有限应变的差值，发现应变差值在晶体剧烈变形区域内较强，对金属晶体Cu位错应变场的计算表明这种应变差异可以用来描述位错的运动状态和芯域结构.该方法可为评估晶体缺陷附近应变状态提供依据.

Elastic strain calculation in the macro-scale based on the crystal structure in the micro-scale

A new method for calculating elastic strains in the macro-scale is proposed based on the crystal structure in the micro-scale. This method is validated by analyzing the elastic strain field of a metal crystal Fe in body-centered-cubic structure, since the calculating results are consistent with predictions from continuum theory very well. Infinitesimal strain and finite strain are further discussed. Results show that there is almost no difference between the two strain fields, except in the area severely deformed. Thus, the strain states in the regions around a crystal defect can be estimated by this new method. As an example, the core structure of dislocation can be described by the strain difference, according to the strain calculation of Cu dislocation.