This research will conduct novel photoelasticity experiments by which local, normal and tangential stresses at the roll-work interface will be measured in the metal rolling process using the birefringent properties of sapphire rolls. The photoelastic investigation will provide the local coefficient of friction at the interface. Realistic work materials such as steel, copper and aluminum will be rolled using the sapphire rolls. The key focus will be to measure the interfacial friction coefficients using this technique. These measured values will be compared with those computed using a finite element method utilizing measured interface velocities. The longer range objective of this work is to develop a reliable analytical tool for rolling and similar forming processes and at the same time to gain a better understanding of the frictional conditions that are present in these processes.
