The strain hardening exponent (n) in the stress-strain relationship of metals and alloys is an indicator of their stretchability during press forming operations. The larger the n value, the more the material can deform before instability, and the material can be stretched further before necking starts.This paper aims to investigate work hardening behavior of dual phase steels. A series of dual-phase (DP) steels containing ferrite and martensite with different volume fractions of martensite (V_m) were produced by in-tercritical heat treatment. Work hardening behavior was analyzed in terms of Holloman analysis. Results showed that in DP steels with less than %50 V_m, the work hardening took place in one stage and the work hardening exponent increased with increasing V_m. By increasing the volume fraction of martensite (V_m>%50) more than one stage will be observed in the Holloman analysis.
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