Changes of bulk flow properties of two different types of titanium dioxide powders were measured at room temperature and 500 degrees C using the High Temperature Annular Shear Cell. A significant increase of the macroscopic bulk flow properties was observed with increasing temperature, in particular with regard to the unconfined yield strength. A theoretical modelling procedure was proposed with the aim to relate the measured properties to the microscopic interactions between particles. The results indicated that the model might provide a good match with the experimental data if proper values for the model's parameters are taken into account (C) 2016 Elsevier B.V. All rights reserved.