Strain softening behaviour of Pb–0.064Ca–0.44Sn wrought sheet

Abstract

AbstractStrain softening in a wrought Pb–Ca–Sn battery alloy is explained by the formation of shear bands during subsequent deformation. It is shown that these bands develop as a result of geometric softening, but once they exist the localized deformation in these bands causes shearing and subsequent dissolution of precipitates producing a substantial loss of strength. Adiabatic heating in the shear bands promotes localized dissolution of precipitates and recrystallization. As the reduction in rolling is increased the number of shear bands increases while their strength decreases. This leads to a decrease in maximum tensile strength and an increase in elongation to fracture.