Amorphization anisotropy and the internal of amorphous layer in diamond nanoscale friction

作者：Yang Ning; Zong WenJun^*; Li ZengQiang; Sun Tao

来源：Computational Materials Science, 2014, 95: 551-556.

DOI：10.1016/j.commatsci.2014.08.040

• Diamond crystal
• Frictional sliding
• MD simulation
• Amorphization

In this work, molecular dynamic (MD) simulation is employed to investigate the formation and evolution of amorphous carbons in the surface layer of diamond crystal as the frictional sliding is performed on diamond (100) plane. Simulation results reveal that the formation of amorphous carbons at the sliding interface is inevitable due to the friction. In this case, transformation from diamond sp(3) hybridized carbons to sp(2) hybridization structures is dominant. More interestingly, most of the sp hybridized carbons appear on the topmost surface of the amorphous layer. Amorphization rate in sliding along the [100] direction is greater than that along the [110] direction due to the smaller resistance forces. In the light of the velocity variation of carbon atoms, the amorphous layer is divided into two layers, i.e. the coherent layer and transition layer. Moreover, a density transition region appears with the formation of amorphous carbons, and the thickness of transition region can be used to characterize the amorphization degree.

• 出版日期2014-12
• 单位哈尔滨工业大学