MECHANICAL BEHAVIOUR OF A SANDWICH PANEL AFTER IMPACT

Object of this work is an hybrid material made of two external layers of steel and an inner core of polyolefin. The purpose of this research is to evaluate the structural response after impact of the hybrid material and define its fatigue parameters using a particular thermographic method applied on static tensile tests. In fact, according to the literature, monitoring the surface temperature of a specimen during tensile tests with IR-thermal camera, it is possible to relate the thermal trend to the fatigue behaviour of the tested material. Three sets of specimen are tested, full hybrid panels (3 layers), half sandwich (2 layers) and single metal sheet, each one impacted with three increasing energy levels. The thermographic technique resulted to be also a valid tool to detect the residual stresses present into the material after impact and to make both qualitative and quantitative consideration about it.