Grain growth in capped steel

Abstract

The rate of grain growth during subcritical annealing at temperatures from 550 to 700 °C was determined for three capped steel samples, each of which had been given a range of prior cold reductions. The initial recrystallized grain size was finer for a higher carbon content and higher reductions. Except for short times at 550 °C, the rate of grain growth at each temperature for each reduction/sample combination obeyed the relationshipD =kt ⁿ and the value ofn was independent of carbon content and cold reduction. The rate of grain growth was a function of instantaneous grain size only for a specific reduction/sample combination but was not the same for different reductions of the same sample which had the same grain size. The material consequently has a memory for prior cold reduction. Grain size distribution changes can account for the deviation of grain growth rates for short times at 550 °C from the general relationship. They do not explain the influence of prior cold reduction.