MONTE-CARLO AND MOLECULAR-DYNAMICS INVESTIGATION OF [001] TWIST BOUNDARIES IN CU3AU AT T=0 K

Sixteen [001] twist boundaries in Cu3Au spanning a wide range of misor ientation angles are investigated at T = 0 K using the molecular dynam ics and Monte Carlo techniques within the framework of the coincident site lattice approach. Grain boundary (GB) energies vary smoothly with misorientation angle and are described satisfactorily by formulas der ived from the theory of dislocations. The equilibrium volume expansion at the GB, and relaxations parallel and normal to the GB plotted agai nst misorientation angle theta all follow Read-Shockley type behaviors . The energies of the unrelaxed GB's are found to be essentially indep endent of misorientation angle. The structure of low-angle GB's is fou nd to be in agreement with theoretical expectations. Relaxation parall el to the GB works complementarily to relaxation normal to it so as to optimally fix the destroyed stacking at the GB due to twist.