Crushworthiness of polymeric foam used as core composite sandwich structure

Abstract

PUR foam has been used extensively as core of sandwich structures in the aerospace and automobile industries. The understanding of their behaviour under crush conditions is extremely important for the design and manufacturing of these engineering structures since crush problems are directly related to structural integrity and safety requirements. In this paper, selected foam cored polymer sandwich beam were subjected to static three point bend tests. The beams were loaded beyond first failure to study the nonlinear post failure behaviour. Provided the beam fails in shear of core and skin delamination. The post failure response is dominated by the crushing of the core and upper skin compression. A theoretical model by Mines and Jones is used to simulate the post failure response of the beams. The model assumes an idealized plastic hinge in the central loading point and relates the beam constituent material properties to the beam overall response. The beams were also subjected with impact test. The impact response of foam based sandwich structures has been investigated using a build-up falling weight impact method and load cell system.