铝单晶中位错交割过程的分子动力学模拟

MOLECULAR DYNAMICS SIMULATION OF INTERSECTION OF DISLOCATIONS IN ALUMINUM

利用EAM势对含160万个原子的Al单晶中位错的交割过程进行了分子动力学模拟.结果表明,当处在不同滑移面上的两个位错相交后,有可能产生1/3空位或1/3间隙原子,它们是晶体中的最小点缺陷,可作为相交位错的节点而单独存在.也可由1/3空位列或1/3间隙原子构成扩展割阶.不同类型的位错相交后,在运动位错的后面可留下一列空位或一列间隙原子,但也可能不留下点缺陷.

The molecular dynamics method is used to simulate intersection of dislocations in aluminum containing 1.6 x 10(6) atoms by EAM potential. The results show that after the intersection of dislocations located on different slip planes, one-third vacancy or one-third interstitial can be generated, which is the smallest point defect in the crystal instead of unit vacancy or interstitial. The one-third vacancy or one-third interstitial can exist alone as a constriction of the intersection of dislocations; or a row of one-third vacancies or one-third interstitials composing an extended jog. Depending upon the type of the intersected dislocations there could be a trail of vacancies, interstitials, or nothing behind the moving dislocation.