ltra-low carbon interstitial-free (IF) sheet steel can offer both good formability and adequate strength for auto body panels. These steels can be designed to achieve a 30-60 MPa increase in strength after press forming and during baking. This increase in yield strength is referred to as bake hardening, ;The objective of this research is to study the evolution of solute carbon and precipitates during the simulated continuous annealing of various microalloyed IF steels. A simulated bake hardening process was developed and different continuous annealing parameters (temperature, time, cooling rate) were studied to determine their effects on the ;The determination of the solute carbon content after various annealing cycles was determined by measurements of the aging index and of activation volume by strain rate change experiments. The solute carbon concentration was correlated with the previous
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