The defect structure in molybdenum single crystals deformed in plane strain

Abstract

Single crystals of molybdenum deformed in plane strain have been examined in conventional 100 kV and 800 kV transmission electron microscopy. Specimens compressed along <110> and free to extend along <001> work-harden more slowly at strains above ∼0.09 than crystals free to extend along <110>, but initially they work-harden more rapidly. The work-hardening behaviour at strains >0.09 can be understood in terms of the different dislocation densities and arrangements observed at 800 kV. The behaviour at low strains cannot be assessed accurately with the present plane-strain apparatus but some latent hardening tests have been carried out (which in fact show latent softening is observed) and these observations appear to throw some light on the work-hardening rate at low strains.