Effect of Coiling Temperature on Ti(C,N) Precipitation and Properties of Batch Annealed DC06EK Enamel Steel

Abstract

The effects of hot-strip coiling temperature on Ti(C,N) precipitation, texture and hydrogen permeation behavior in DC06EK enamel steel were investigated by TEM, EBSD test and electrochemical hydrogen permeation experiment. It was found that the Ti(C,N) particles in hot-strip coarsened with increasing coiling temperature, whereas after cold-rolling and annealing, the size difference of Ti(C,N) particles was lessened. The hot-strip coiling temperature has a significant impact on the recrystallized texture in the subsequent cold-rolled and annealed sheet. Hot-strip using high temperature (700 °C) coiling leads to strong {111} recrystallized texture in annealed sheet, with peak intensity 9.2. On the contrary, in annealed sheets using hot-strip coiling at 650 °C, their {111} recrystallized textures were weaker, which was also reflected in their r _m values. Even though the hydrogen diffusion coefficient is slightly lower (7.76×10^-5 mm²/s) in annealed sheet using low temperature coiling (600 °C), appropriately higher coiling temperature is more suitable for DC06EK enamel steel combining both good drawability and fish-scale resistance.

Keywords

enamel steel / coiling temperature / Ti(C,N) / γ-fiber texture / hydrogen diffusion

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