Mechanical Properties of Al/PU/Perforated CU/PU/Al Sandwich Composites

Abstract

In the present work, the warm roll bonding (WRB) technique was adopted to fabricate 3 layers of Aluminum-perforated Copper 260-Aluminum (AL/perforated CU/AL), and five layers of (AL/Polyurethane (PU)/perforated CU/PU/AL) sandwich composites. Two different tests were adopted, namely peel test and small punch test (SPT), to study the peel strength and flexural behavior of these sandwich composites, respectively. The main manufacturing parameters, including interface properties, rolling speed, and the number of passes, which control the strength and integrity of these sandwich composites were studied experimentally. Furthermore, the three-dimensional finite element method was carried out to study the effect of the presence of pre-crack on the peeling test and SPT specimens numerically. The present results indicated that the peeling resistance is mainly dependent on the roughness of the interface and elapsed time in manufacturing processes. The flexural behavior of sandwich composites measured from SPT agrees with the first principles of mechanics of materials, i.e. there is a marginal effect of the bond strength between the layers.

Keywords:
Warm roll bonding; aluminum sandwich composites; Small Punch Test specimens; peel test; cracked specimens