arXiv subjects

T. Jayakumar

Publications and source records attributed to T. Jayakumar.

3 recordsLinked to original sources

arXiv2014

Molecular Dynamics Simulations of Tensile Behavior of Copper

Molecular dynamics simulations on tensile deformation of initially defect free single crystal copper nanowire oriented in <001>{100} has been carried out at 10 K under adiabatic and isothermal loading conditions. The tensile behaviour was characterized by sharp rise in stress in elastic regime followed by sudden drop at the point of dislocation nucleation. The important finding is that the variation in dislocation density is correlated with the observed stress-strain response. Several interesting micro- structural features were observed during tensile deformation such as slip, phase transformation and pentagonal structure in necking region affecting the plastic deformation behaviour of single crystal copper nanowire.

cond-mat.mtrl-sci↗

arXiv2014

Deformation behaviour of body centered cubic Fe nanowires under tensile and compressive loading

Molecular Dynamics (MD) simulations have been carried out to investigate the deformation behaviour of <110>/{111} body centered cubic (BCC) Fe nanowires under tensile and compressive loading. An embedded atom method (EAM) potential was used to describe the interatomic interactions. The simulations were carried out at 10 K with a constant strain rate of $1\times10^{8}$ $s^{-1}$. The results indicate a significant differences in deformation mechanisms under tensile and compressive loading. Under tensile loading, the deformation occurs by the slip of full dislocations, While under compressive loading twinning was observed as the dominant mode of deformation. The tension-compression asymmetry in deformation mechanisms of BCC Fe nanowires is attributed to twinning-antitwinning asymmetry of 1/6<111> partial dislocation on {112} planes. We further explain the mechanism of dislocation pile up in tensile loading and twin growth in compressive loading.

cond-mat.mtrl-sci↗

arXiv2006

Lattice Misfit Measurement in Inconel 625 by X-Ray Diffraction Technique

Determination of lattice misfit and microstructural parameters of the coherent precipitates in Ni based alloy Inconel-625 is a challenging problem as their peaks are completely overlapping among themselves and also with the matrix. We have used a novel X-ray diffraction technique on the bulk samples of Inconel 625 at different heat-treated conditions to determine the lattice parameters, the lattice misfit of the coherent precipitates with the matrix and their microstructural parameters like size and strain.

cond-mat.mtrl-sci↗