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We study the effect of solute segregation on pyramidal to basal transformation of 〈 c + a 〉 edge dislocations in a model Mg-Y alloy, using a hybrid Monte Carlo/Molecular Dynamics method. While a random solute distribution has no appreciable effect on this undesirable transition, a solute cloud around the dislocation slows and effectively prevents it in case of Mg-3 at % Y alloy. Comparing with the time scale required for diffusion of Y to the dislocation, suggests that segregation of Y and other fast diffusing elements can be engineered to prohibit this glissile to sessile transition, and stabilize the pyramidal glide of 〈 c + a 〉 dislocations. [ABSTRACT FROM AUTHOR]

Nanoglasses consist of glassy grains connected by an amorphous interface. While internal interfaces in nanoglasses help to prevent brittle failure, they are usually not beneficial to the glasses overall strength. In this molecular dynamics study, we manipulate the glass–glass interfaces of a Cu–Zr nanoglass, such that they are replaced by stronger crystalline interphases. Analogous to grain boundary strengthening in crystalline materials, we show that it is possible to reinforce the nanoglass without compromising its ductility. [ABSTRACT FROM AUTHOR]