Molecular dynamics (MD) method was conducted on four types of symmetric tilt grain boundaries (GBs) in body-centered cubic (BCC) Fe–9Cr alloy. The formation energy and segregation energy of different types of defects (interstitial and vacancy) was firstly calculated in each system, and the GB energy and width were also calculated. It is found that the Fe interstitials have higher segregation energy than Cr interstitials for all GB systems, which can explain energetic drive of the defect behavior in GB systems. By analyzing the defect production in GB systems and comparing them with those in single crystal, it was found that more interstitials than vacancies disappeared due to the existence of GB. But the influence of GB varies between GB types. The migration of GB was only found in ∑25(430) possibly because of the temperature gradient during the cascade evolution.

对体心立方（BCC）Fe-9Cr合金中的四种对称倾斜晶界（GBs）进行了分子动力学（MD）方法。首先在每个系统中计算不同类型缺陷（间隙和空位）的形成能和偏析能，并计算GB能量和宽度。已发现，对于所有GB系统，Fe隙间的偏析能量均比Cr隙高，这可以解释GB体系中缺陷行为的能量驱动。通过分析GB系统中的缺陷产生并将其与单晶中的缺陷进行比较，发现由于GB的存在，间隙消失的数量多于空位。但是GB的影响因GB类型而异。