INFLUENCE OF DYNAMIC STRAIN AGING ON THE CREEP DUCTILITY OF SOLID SOLUTION ALLOYS.

In this paper the correlation between creep ductility and stress in solid solution alloy is examined. The creep ductility is a strong function of the stress exponent for steady state creep. The elongation maximum experimentally observed at about 10 MPa in Al-Mg alloys at 643 K is due to the low stress exponent. The low stress exponent spreads the deformation out over the whole gauge length, which results in an elongation maximum. This study also predicts the elongation maximum. This study also predicts the elongation minimum at about 55 MPa at 533 K. The decrease in elongation observed in the high stress region at 533 K is due to the high stress exponent. The high stress exponent concentrates the deformation in the necked region, which results in a decrease in elongation. The relation between the stress exponent and the fracture type is also examined.