Molecular Dynamics Simulations Of Cu Nanocrystal Model Toward Mechanical Properties With Periodical Cyclic Loading

Cycle fatigue,as the mainly destroying style in current metal material for engineering,can be lucubrated by means of nano-scale exploring and there is a high probability for this moment to make a break through via improving nano-material and then put this technique into the macroscopic metal materials.For this paper,we adopt the analytical EAM function and method of temperature controlled by welding speed to proceed the systematical single and twin crystal copper nanorods simulation by MD(Molecular Dynamics)with the periodical cyclic loading to elucidate the mechanical properties and features.Single crystal copper nanorods under z uniaxial cyclic periodical loading along the orientation of [100]?[110]and [111]has been simulated by MD to illustrate the mechanical properties and different between periodical load and non-periodical load.And after simulations,we compare the characters and futures in periodical load and non-periodical respectively and find that the different periodical load have different maximum stress,and when loading to yield,the periodical loading simulations have shown how the half-period steps influenced the mechanical properties,and we can obviously find the periodical load with regard to single crystal copper nanorods is not stable as non-periodical loading.About twin copper crystal,the maximum tensile stress is smaller than that single crystal under tensile loading with non-period.However in periodical loading cases we find twin-crystal nanorods have an obviously virtue different mechanical behaviors comparing with periodical loading in single crystal.At the procedure of simulation toward twin crystal copper nanocubes,the twin crystal nanocubes presented the yielding stress is not likes that the single crystal nanocubes would beforehand getting to yield.Meanwhile,the ability of anti-fatigue for twin crystal atomic system is better than single crystal copper and that is a good perspective for further researching anti-fatigue and damage resistance nano-metal material which will be an arduous and challenging systematic issue in engineering waiting to be worked out.