Dangqiang Wang¹, Hai Mei^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.1, pp. 1-1, 2023, DOI:10.32604/icces.2023.09455

Abstract The densification process of sintered alumina is mainly controlled by surface, lattice, and interface diffusion, and many experimental researches show that heating rate can affect the transfer of matter. Thus, to further reveal the effect of heating rate on sintering mechanism of alumina nanoparticle, molecular dynamic simulations were performed at five different heating rates to examine the migration of atoms and evolution of microstructure in heating stage. Results show that the sintering process of heating is a typical thermal activation process. High displacement response temperature is caused by high heating rate, which results in the mechanism of atomic migration quickly… More >

Jiachen Guo^1,2, Yunfei Xu², Zhenyu Jiang^1,*, Xiaoyi Liu², Yang Cai^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.2, pp. 611-623, 2020, DOI:10.32604/cmes.2020.011148

Abstract Both of Buckling and post-buckling are fundamental problems of geometric nonlinearity in solid mechanics. With the rapid development of nanotechnology in recent years, buckling behaviors in nanobeams receive more attention due to its applications in sensors, actuators, transistors, probes, and resonators in nanoelectromechanical systems (NEMS) and biotechnology. In this work, buckling and post-buckling of copper nanobeam under uniaxial compression are investigated with theoretical analysis and atomistic simulations. Different cross sections are explored for the consideration of surface effects. To avoid complicated high order buckling modes, a stressbased simplified model is proposed to analyze the critical strain for buckling, maximum deflection,… More >

Xiangli Liu¹, S. I. Golubov¹, C. H. Woo^1,2, Hanchen Huang³

CMES-Computer Modeling in Engineering & Sciences, Vol.5, No.6, pp. 527-540, 2004, DOI:10.3970/cmes.2004.005.527

Abstract A Green’s function technique is developed for the relaxation of simulation cell boundaries in the modelling of dislocation interactions using molecular dynamics. This method allows the replacement of fixed or periodical boundary conditions with flexible boundary conditions, thus minimizing the artificial effects due to images forces introduced by the fixed boundary condition, or the periodic repetition of simulation cells. The effectiveness of the Green’s function in the removal of the fixed boundary image forces is first checked in the atomistic simulation involving the glide of the a/2<110> dislocation in bcc tungsten. This method is then applied to study the reaction… More >

Marcin Maździarz¹, Marcin Gajewski²

CMES-Computer Modeling in Engineering & Sciences, Vol.105, No.2, pp. 123-150, 2015, DOI:10.3970/cmes.2015.105.123

Abstract In this paper, the choice and parametrisation of finite deformation polyconvex isotropic hyperelastic models to describe the behaviour of a class of defect-free monocrystalline metal materials at the molecular level is examined. The article discusses some physical, mathematical and numerical demands which in our opinion should be fulfilled by elasticity models to be useful. A set of molecular numerical tests for aluminium and tungsten providing data for the fitting of a hyperelastic model was performed, and an algorithm for parametrisation is discussed. The proposed models with optimised parameters are superior to those used in non-linear mechanics of crystals. More >

Xiaozhi Tang¹, Yafang Guo¹, Yu Gao¹

CMC-Computers, Materials & Continua, Vol.23, No.1, pp. 1-8, 2011, DOI:10.3970/cmc.2011.023.001

Abstract Atomistic simulations were performed to study the nanoindentation for two kinds of FCC metals, aluminum and copper. Due to the higher stacking faults in aluminum than in copper, two different deformation mechanisms were observed in our simulation under exactly the same simulation condition. Aluminum and copper also showed different mechanical properties in the unloading stage. The influence of stacking sequence along the loading direction on deformation mechanism was also investigated in this paper. More >