was proven by extensional rheology measurements.
The mean loads yielded by steel components under quasi-static and impact testing conditions are shown to compare favorably with theoretical predictions of mean loads which suitably account for strain hardening
and dynamic rate effects.
The stress-strain behaviors of samples change from strain hardening
to strain softening with dry density increasing.
Comparison of the constant K specified in the material of the sheets of the material DC 04 with the measured values obtained for the examined materials of the F-M steels (Table 2) show that the constant K (K = 1052 - 1336 MPa) of all materials was higher that of a steel sheets DC 04 and the values of the strain hardening
exponent of materials produced by intercritical annealing were greater or comparable with the DC 04.
We have found that the Strain Hardening
test delivers reproducible results which very nicely correlate with results of time-consuming traditional slow crack growth tests -- but in a much shorter time," says Frans Scholten, expert on material testing at Kiwa Technology.
Two ways to accomplish the objective include (1) adding wall thickness and (2) developing tube and fitting processes that would enhance strain hardening
while minimizing deformation due to increased hoop stress.
The thermal softening and strain hardening
values predicted by the ZA model are incorrect as found by Jaspers [10, 17].
Fracture phenomenon during pull-out process is described in four stages, which are; pre-slip, slip, transition, and strain hardening
Some types of AHSS have a higher strain hardening
capacity resulting in a strength-ductility balance superior to conventional steels.
Shortly after yielding, the uniform deformation with strain hardening
begins and then the AE energy (or rms voltage) gradually reduces to a very low, hardly distinguishable from noise, level while the median frequency is monotonically increasing on average with the flow stress.
They found a typical ductile behaviour with a yield point, neck propagation, and strain hardening
up to a temperature of 155[degrees]C.
The most interesting results, registered at such action on the investigated joints, are abnormal tensile properties and character of strain hardening
of a specimen, whereby main attention has to be paid to elongation of the specimen .