Work Hardening of Continuously Annealed Dual Phase Steels

Abstract

A" the baris oJ cOlltilluum model , theoretical equatioll which describes a stress-straill cllrve oJ dual phase steel is built up Jrom the stress-straill curves oJ each composite phase. The comparisoll oJ theorelical result, with experimenla l onts is made on the cOlltilll/ously alll/ealed dual phase steel which is composed oJ Jerrite and martensite . Agreemenl betweell them is esselltially good Jor volume Jraction oJ martensite below 0. 2. The theoretica l equation makes clear the wa)'s Jor improvillg ductility oJ high slrenglh dual phase <teets. They are im/Jroving the tensile slrellglhelongation relalionship oJ soft phase, strellgthening the hard phase (IS high as p ossible, desirably to Ihe level oJ martellsite, and cOlilrollilig Ihe volume fraction oJ hard phase below 0 .2.