The mechanical property and deformation mechanism of twinned gold nanowire with non-uniform distribution of twinned boundaries (TBs) are studied by the molecular dynamics (MD) method. It is found that the twin boundary spacing (TBS) has a great effect on the strength and plasticity of the nanowires with uniform distribution of TBs. And the strength enhances with the decrease of TBS, while its plasticity declines. For the nanowires with non-uniform distribution of TBs, the differences in distribution among different TBSs have little effect on the Young’s modulus or strength, and the compromise in strength appears. But the differences have a remarkable effect on the plasticity of twinned gold nanowire. The twinned gold nanowire with higher local symmetry ratio has better plasticity. The initial dislocations always form in the largest TBS and the fracture always appears at or near the twin boundaries adjacent to the smallest TBS. Some simulation results are consistent with the experimental results.

采用分子动力学（MD）方法研究了孪晶边界（TBs）分布不均匀的孪晶金纳米线的力学性能和变形机制。发现孪晶界间距(TBS)对TBs均匀分布的纳米线的强度和塑性有很大影响。且强度随着TBS的降低而增强，而塑性下降。对于TBs分布不均匀的纳米线，不同TBSs分布的差异对杨氏模量或强度影响不大，出现强度折衷。但这些差异对孪晶金纳米线的可塑性有显着影响。具有较高局部对称比的孪晶金纳米线具有较好的可塑性。初始位错总是在最大的 TBS 中形成，而断裂总是出现在与最小 TBS 相邻的孪晶界处或附近。部分模拟结果与实验结果一致。