Effect of Continuous Annealing Process on Microstructure and Properties of Ultra-Low Carbon Cold Rolled Enamel Steel

摘要

The influence of the continuous annealing process on the microstructure and mechanical properties of ultra-low carbon cold rolled enamel steel was studied. The inicrostructural evolution of the test steel, precipitation of second-phase particles, the time of hydrogen permeation, and the change of the mechanical properties were analyzed with optical, scanning electron, and transmission electron microscopes. The results show that ferrife grain sizes were 5-30 um after the continuous annealing process. The precipitates were Ti(C,N), Ti_4C_2S_2 and MnS. With increased soaking temperature, the particle sizes increased while the number of precipitates and hydrogen permeation time decreased. The hydrogen permeation time decreased sharply at 870°C (1598°F). The annealing process had little effect on strength, and the best comprehensive properties were obtained at 850°C (1562°F).