Study of the intrinsic dissipation associated to the plastic work induced by a ball impact

摘要

This paper presents a measurement method of the thermal dissipation in metallic samples submitted to a plastic strain. Its interest is to extend the field of experimental investigation of the irreversible plastic transformations. The method is applied to the quantification of the thermal dissipation effects associated to the impact of a ball on a thin metallic sample. The final aim of the study consists in proposing a complementary method for controlling and monitoring the shot-peening process. The temperature rise at the rear face after the impact of the ball at the front-face is measured by infrared thermography. Then, the dissipated heat is deduced from the registered thermograms, via a parameter estimation procedure, by a comparison with a specially developed heat diffusion model. The first results presented here show that a preliminary shot-peening of the samples induces a reduction in the energy dissipated during the impact. Then, a specific study has been carried out in order to point out the diminution of the dissipated heat with the number of previous shots.