The Peierls stress for a [111]-screw dislocation in bcc Tantalum is calculated using an embedded atom potential. More importantly, a method is presented which allows accurate calculations of the Peierls stress in the smallest periodic cells. This method can be easily applied to ab initio calculations, where only the smallest unit cells capable of containing a dislocation can be conviently used....

The Peierls stress for a [111]-screw dislocation in bcc Tantalum is calculated using an embedded atom potential. More importantly, a method is presented which allows accurate calculations of the Peierls stress in the smallest periodic cells. This method can be easily applied to ab initio calculations, where only the smallest unit cells capable of containing a dislocation can be conviently used....

A 26 year old man was referred to us with extensor pollicis longus dysfunction (EPL), and investigation revealed a fracture of the trapezium (left) and carpo-metacarpal joint dislocation of the thumb. Operative exploration revealed mechanical displacement of the tendon secondary to fracture dislocation of the trapezium as the cause for EPL dysfunction. The lesion was managed with an open reduct...

This paper is concerned with the electroelastic potentials and the fracture parameters of a twinedge-cracked piezoelectric bimaterial strip with a screw dislocation. By means of conformal mapping technique and the known dislocation solution, the antiplane displacement and inplane electric potentials are obtained in closed-form. The intensity factors and the energy release rate are extracted exp...

Solution strengthening is a well-known approach to tailoring the mechanical properties of structural alloys. Ultimately, the properties of the dislocation/solute interaction are rooted in the electronic structure of the alloy. Accordingly, we compute the electronic structure associated with, and the energy barriers to dislocation cross-slip. The energy barriers so obtained can be used in the de...

Numerical solutions of a one dimensional model of screw dislocation walls (twist boundaries) are explored. The model is an exact reduction of the 3D system of partial differential equations of Field Dislocation Mechanics. It shares features of both Ginzburg-Landau (GL) type gradient flow equations as well as hyperbolic conservation laws, but is qualitatively different from both. We demonstrate ...

The stress distribution and dislocation forces for screw dislocations near cavities and straight boundaries are examined, depending on the selected cut used to impose a displacement discontinuity and create a dislocation. The location of the equilibrium dislocation position is determined in each considered case. The slip-induced stress amplification in thin ligaments between a cavity and a stra...