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Electron backscattered diffraction is employed to explore the dependence of deformation reduction, strain rate and temperature on microstructure and texture evolution of CP Ti after hot compression tests. It is found that {10-12} twinning only occurs at the early stage of deformation. As the strain increases, the {10-12} twinning is suppressed while {10-11} twinning appears. Three peaks are found in the misorientation frequency-distribution corresponding to basal fiber texture, {10-11} and {10-12} twinning, respectively. The data for the stable subgrain size and amount of {10-11} twins are separated into two groups at logZ = 13. Above this value, twinning is observed and the subgrain size is much finer, < 3μm. It is concluded that the presence of {10-11} twinning is the key factor for effectively reducing the deformed grain size. After deformation, three (0001) texture components can be found, one close to the compression direction, CD, one 10~30° to CD and another 45° to CD., QC 20100819

A model is developed to predict the flow stress for single peak dynamic recrystallization during hot working based on the analysis of the mechanism of the process. The model reveals the dependence of flow stress on strain, strain rate, temperature and microstructure. The flow stress in the recrystallized zone is derived by an integral with the recrystallized volume fraction as the variable. The correlation between the microscopic variable and flow stress is investigated with the model. The performance of the model is evaluated through application on magnesium alloy AZ31D. The mean error of flow stress between the experimental and predicted results is examined. Good agreement between the predicted and experimental data is achieved. All mean errors are between −5.9% and 6.7%., QC 20100819