运用原子-有限元法(FEAt)研究了裂纹在低温加载条件下的脆性解理扩展.原子模拟结果表明:在低温和一定外部载荷条件下,bcc-Fe中{100}<011>边界I型裂纹的扩展过程是一个裂尖原子键断裂与层错或孪晶扩展相伴随的过程.裂纹低温脆性解理扩展的最大速率可达到1 125 m/s,即约为0.6VR .相应的有限元分析表明,裂尖存在较大的能量和应力集中,这是导致裂尖原子键断裂及弹性孪晶形成的原因.
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