Dislocation multiplication in bcc molybdenum: a dislocation dynamics simulation

Plastic deformation of Mo single crystals is examined by direct simulation of dislocation dynamics under stress. Initial dislocation populations bare made to mimic real dislocation microstructures observed in transmission ele ctron microscopy cross-sections of pure annealed Mo single crystals. No a p riori sources for dislocation multiplication are introduced, and yet multip lication takes place through a sequence involving aggregation of grown-in s uperjogs, bowing of screw dislocation segments and fast lateral motion of e dge segments, producing a large number of elongated loops and a characteris tic cross-grid pattern of screw dislocations.