Austenite grain growth kinetics and the grain size distribution

The aims of this work are to assess the kinetics of austenite grain growth, and to estimate the three dimensional grain size distribution. Measurements are to be used for the validation of a statistical model for the estimation of the kinetics of austenite grain growth during hot strip rolling. A series of tests are performed with two industrial plain carbon steels in the temperature range from 950°C to 1150°C. Grain size is measured by standard manual procedures and by the use of image analysis equipment. Systematic errors in the measurements are identified. A correction is proposed to account for the systematic error in the measurement of the two dimensional grain size distribution by the use of image analysis. The kinetics of austenite grain growth are discussed and the influence of second phase particles is observed. Results are described well by a statistical model for grain growth. A number of methods for the estimation of the three dimensional grain size distribution are compared. It is concluded that the method proposed by Matsuura and Itoh is the most suitable.Applied Science, Faculty ofMaterials Engineering, Department ofGraduat