The molecular dynamics (MD) simulation is performed to obtain the mechanical properties and plastic deformation mechanism of bicrystal structural tungsten (BS W) with equilibrium grain boundaries (EGBs) and non-equilibrium grain boundaries (NEGBs) under tension at different strain rates. The BS W with NEGBs has shown excellent comprehensive mechanical properties, and its yield strength is only about 1.5 Gpa (~10%) lower than that of the BS W with EGBs. The yield strain of BS W with NEGBS is about double than that with EGBs. The micro-deformation mechanisms for BS W with NEGBs under tension are dislocation emission and movement, GBs interaction, and phase transition. However, the failure modes of BS W with EGBs are intergranular brittle fracture of crack near the GBs, and the strain rate has little effect on the fracture. The phase transition mechanism for BS W with NEGBs under the tension loading strain rate of 0.0001 ps⁻¹ is atomic slippage, but that of 0.001 ps⁻¹ is stress concentration induced quasi-reconstructive phase transition. At the loading strain rate of 0.0001 ps⁻¹, dislocation emission and movement to the GBs would form the non-slippable crack dislocations for crack initiation. However, at the loading strain rate of 0.001 ps⁻¹, the crack propagation is considered as a zigzag-shaped form on account that the phase transition induced stress relaxation. The NEGBs could improve plasticity without sacrificing strength, providing a theoretical method for nano-structure design, material modification, and sustainable material plain.

进行了分子动力学（MD）模拟，获得了在不同应变速率下，具有平衡晶界（EGBs）和非平衡晶界（NEGBs）的双晶结构钨（BS W）的力学性能和塑性变形机制。带有NEGB的BS W已显示出优异的综合机械性能，其屈服强度仅比带有EGB的BS W低约1.5 Gpa（〜10％）。使用NEGBS的BS W的屈服应变约为使用EGBs的BS W的屈服应变。带有NEGBs的BS W的微变形机制为位错发射和运动，GBs相互作用和相变。然而，带EGB的BS W的破坏模式是GBs附近的裂纹的晶间脆性断裂，应变速率对断裂的影响很小。^-1是原子滑移，但0.001 ps ^-1的滑移是应力集中引起的准重构相变。在0.0001 ps ^-1的加载应变速率下，位错发射和向GBs的移动将形成用于裂纹萌生的不可滑动裂纹位错。但是，在0.001 ps ^-1的加载应变速率下，由于相变引起应力松弛，因此将裂纹扩展视为之字形。NEGB可以在不牺牲强度的情况下提高可塑性，为纳米结构设计，材料改性和可持续的材料平原提供了一种理论方法。