Premium
The correlation between dislocation structure and work‐hardening behaviour of molybdenum single crystals deformed at 293° K
Author(s) -
Luft A.
Publication year - 1970
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.19700420143
Subject(s) - dislocation , materials science , work hardening , molybdenum , crystallography , transmission electron microscopy , peierls stress , strain hardening exponent , hardening (computing) , flow stress , condensed matter physics , composite material , dislocation creep , metallurgy , strain rate , microstructure , nanotechnology , chemistry , physics , layer (electronics)
The dislocation structure of high‐purity molybdenum single crystals after tensile deformation at 293° K is studied by transmission electron microscopy. Dislocation and debris densities were determined as function of strain. The stress–strain curve is characterized by a high initial work‐hardening rate and a subsequent stress plateau. At low strains long jogged screw dislocations and dislocation debris predominate while at higher strains additionally large dislocation tangles are formed. The resolved flow stress τ and screw dislocation density ϱ 1 obey τ = τ 0 + α 1 G b √ϱ 1 with α 1 = 1.1. It is suggested that the interaction between primary and secondary screws involving the formation of jogs, debris, and attractive dislocation junctions is the relevant dislocation strengthening mechanism.