Kinetics of f.c.c. deformation twinning and its relationship to stress-strain behaviour

摘要: Abstract The kinetics of f.c.c. deformation twinning,i.e. the amount twins vs applied strain were determined by quantitative microscopy at various temperatures in a Co-33Ni alloy. kinetic curve has quite parabolic shape and approaches saturation below 50% transformation; however twinning occurs only after critical which is an increasing function temperature. Assuming that nucleate from perfect slip dislocations as proposed Mahajan Chin, volume fraction can be expressed implicit strain. approach to described two parameters are temperature dependent through variation stacking fault energy. Good agreement with experimental results was obtained. An increase flow stress observed where plays important role compared slip. This extra contribution experimentally vary inverse mean size matrix cells between neighbouring twins. dependence been attributed fact act strong obstacles dislocation propagation.