Effect of Cu on the texture evolution and mechanical properties of interstitial-free steels

This study investigates the effect of copper (Cu) addition on the microstructure, texture and mechanical properties of interstitial-free steels. Cu addition altered the recrystallisation behaviour, resulting in a pronounced intensity gradient within the γ-fibre, with an intensified {111} <110> component at the expense of the {111} <112> orientation. This texture evolution increased the average Taylor factor, enhancing yield and tensile strength. However, it also reduced the average r-value and increased planar anisotropy, degrading deep drawability. The underlying mechanism is attributed to Cu segregation at grain boundaries, which retards recrystallisation kinetics and promotes preferential retention of α-fibre components. Thus, Cu addition induces a texture-mediated trade-off between enhanced strength and reduced formability.