A sensor for measuring surface shear stresses in metal forming

The importance of experimental measurement of the frictional stresses at the workpiece die interface in the study of bulk and ring compression testing has been recognised. This research work describes the modification and development of a friction sensor for measuring normal and frictional shear stress without the extrusion of workpiece material into the sensor gap.; Experimental results are shown for the bulk compression and ring compression testing of Aluminium-6061. The results obtained with the cap sensor show this design to be a marked improvement over previous sensors designed to measure frictional stress in metal forming.; Though the experimental results are encouraging, recommendations for future research and improvements to the sensor are given so that the cap sensor can be efficiently utilised in the future.