Dynamic and Impact Deformation Evaluation by Electromotive Force Technique

Abstract

A deformation measurement with a thermocouple was intended to be applied for dynamic and impact deformation test. An electromotive force (Emf) was caused by bending vibration, which was tensioned and compressed alternatively in a steel plate. The Emf increased almost in proportion to the strain magnitude. The impact test was done using a Hopkinson bar made of several kinds of metals. The Emf and strain were measured at same position. Both the Emf and strain were agreed well with each other in timing, though they were different in the direction of increasing and decreasing. There was a linear relationship between the absolute Emf and strain for the steel, copper, aluminum and solder bars.