Critical assessment - the product of tensile strength and elongation as performance parameter of cold-rolled annealed steel grades

The strength-ductility balance of steel families is often compared using the product of ultimate tensile strength (UTS) and total elongation (TE). However, analysis reveals that for a wide strength range exceeding 300 MPa, this product rule cannot accurately describe the tensile data of both single-phase ferritic steels and dual-phase steels. Therefore, it is argued that the product rule has limited value in identifying strength-ductility combinations that are differentiated with respect to conventional C-Mn steels. A baseline equation, wherein TE has an exponential dependence on UTS, is proposed. This equation shows excellent agreement with the strength-ductility data of conventional C-Mn steels as well as quenched (and tempered) martensites in the strength range of 300 to 2000 MPa.