Characterizing thermally activated dislocation mobility

Deformation and fracture behavior of the P91 martensitic steel at high temperatures

“…Detailed description and derivation of the Eqs. (10)- (12) can be found in [22]. The last estimated material property is the strain rate sensitivity described as the slope in the log-log stress-strain plot:…”

Thermally activated deformation of two- and three-variant nanotwinned L10 Au–Cu–Pt

“…These are the activation volume (or more rigorously the activation area, A eff ¼ b À1 V eff ), and a dimensionless dislocation immobilization parameter b [35,36], given as:…”

“…The dislocation immobilization parameter b is the exponent in the powerelaw relation coupling the dislocation velocity and the mobile dislocation density [35,36]; it measures the net rate at which moving dislocations are immobilized during relaxation cycles. Values measured in the present series of experiments are plotted in Fig.…”

Loss of strength in Ni3Al at elevated temperatures

“…between (1 0 ) and (2)), diffusive effects pin practically immobile dislocations, so that the following relaxation starts with a lower mobile dislocation density. In particular, this effect prevents the determination of the microscopic activation volume, though this is straightforward in the case of conventional relaxation series [15]. Finally, figure 5 shows a yield point during constant strain-rate reloading just after the relaxation series.…”