Effect of initial contact location on multiasperity nanocontact: Quasicontinuum Simulation
W. G. Jiang, S. Xu and Z. W. Wang
NANO, 9, 1450004 (2014).


Two nanocontact models with different initial contact locations are built to simulate the process of the multiasperity nanocontact for investigating the er effect of initial contact location on the nanocontact process by using the quasicontinuum method. The indenter is initially located on the top of the middle wave crest (MWC) of the substrate and the top of the wave trough on the left side (LWT) of the substrate, respectively. The microscopic deformation mechanism, the load-displacement curve and the nanohardness-displacement curve are examined. It is found that the deformation mechanisms in the two multiasperity contact models are different. During the initial contact stage, in the MWC model, the twinning deformation dominates the whole contact process, while in the LMT model many Lomer-Cottrell locks are generated in the copper substrate, which inhibits the occurrence of twinning deformation.