EFFECTS OF GRAIN-BOUNDARY CARBIDE ON THE STRESS-STRAIN CURVES OF TYPE-316 STAINLESS-STEEL

The presence of dense grain boundary carbide can result in a decrease in the uniform elongation and an increase in the tensile strength and strain hardening rate of type 316 stainless steel at room temperature. The stress-strain curves are analyzed using the Ludwigson equation σ = k1ε{lunate}n1 + exp (k2 + n2ε{lunate}). It is found than n2and n2 decrease, k1 increases slightly while k2 is not affected by the presence of grain boundary carbide. The strain at which the Ludwigson equation reduces to the Ludwik equation (i.e. σ = k1ε{lunate}n1) decreases with increasing grain size and by the presence of grain boundary carbide. The significance of the results are discussed. © 1990.