The mechanism of work softening in cold-worked molybdenum polycrystals at an elevated temperature

摘要: Abstract It is shown that pure polycrystalline molybdenum predeformd at T 1 = 293 K by rolling exhibits pronounced work softening on subsequent tensile straining an elevated temperature 2 493 . The post-deformation characterized extremely heterogeneous distribution of slip. Transmission electron microscopy investigation the structure change during re-straining clearly indicates basic process formation narrow slip channels in which obstacle dislocation density drastically reduced. From observations interaction with grain boundaries, further evidence obtained channel result mutual annihilation existing dislocations. suggested this initiated local stress concentration and forced to propagate field following groups glide An attempt made interpret observed macroscopic behaviour terms progation solf a work-hardened aggregate.