A systematic first-principles study of surface energies, surface relaxation and Friedel oscillation of magnesium surfaces

Magnesium interatomic potential for simulating plasticity and fracture phenomena

“…The Version of Record is available online at http://dx.doi.org/10.1088/0965-0393/23/1/015004. [42] f Reference [43] g Reference [13] h Reference [44] difficult than nucleation of a dislocations on basal and prismatic planes. The MEP on the pyramidal II plane follows the c + a direction while on the pyramidal I plane, the MEP is more complex.…”

Brittle and ductile crack-tip behavior in magnesium

“…For Mg, earlier studies based on DFT [8,9,10] and MEAM [11] show that the surface energies of several low index planes are similar while the unstable stacking fault energies of different slip systems are starkly different. Experimental work by Bhattacharya et al [7] also observed multiple cleavage planes (basal and prismatic) on fracture surfaces of Mg at low temperatures.…”

“…Given accurate elastic constants, surface energies and the unstable stacking fault energies for the various slip systems, it is straightforward to analyze the crack-tip competition using linear elastic fracture mechanics (LEFM) theory for Griffith cleavage [1] and Rice's criterion [2] for dislocation nucleation within Peierls framework. Theoretical predictions are now providing some of the essential atomistic material properties for Mg, such as the various surface energies, dislocation core structures, and unstable stacking fault energies [8,9,10], so that predictions of crack tip response can be made. However, the assumptions and approximations used in the theory, the discrete nature of the atomic system, crack surface stresses, crack tip geometry, and other effects could shift the competition relative to the theory predictions.…”

Modeling and stabilities of Mg/MgH2 interfaces: A first-principles investigation

“…It should be noted that our first-principles calculation of surface energies is conducted at 0K, where the bond cutting and the surface reconstruction are the two major factors that dictate the surface energies. Previous papers 37,40,41 showed that both of these two effects played an important role on surface energies. Moreover, the contribution of vibration entropy, another factor in determining the surface energies, goes up when the temperature rises so that the two major factors may not be the only determining ones and the surfaces with high surface energies at 0 K may appear.…”