Measurement of Critical Interfacial Temperature by Means of the Thermoelectric Method in Cold Sheet Rolling

Abstract

Temperature at the interface between roll and workpiece in cold sheet rolling is measured by the thermoelectric method. Experiments are carried out using the simulation testing machine of sliding-rolling type on various conditions of roll speed and reduction in thickness. The critical temperature is evaluated by means of investigations on the relation of measured interfacial temperatures to the occurrence of friction pick up. Relation between experimental values and theoretically calculated mean interfacial temperature is examined. The conclusions obtained are as follows ; ( 1 ) The thermoelectric method is effective for the evaluation of the interfacial temperature in cold sheet rolling. ( 2 ) The critical temperature is constant at which a friction pick up occurs from breakage of lubrication film due to frictional heating. ( 3 ) Measured temperatures coincide with calculated values.