Abstract
Metal-polymer sandwich composites have been rapidly replacing metallic materials in aerospace and automobile industries. Their desirable mechanical properties including excellent fatigue and impact strength, as well as damage tolerance, are accomplished without sacrificing the benefit of lightweight. In this study, a three-layer metal-polymer-metal sandwich composite was fabricated using a direct adhesion warm roll bonding (WRB) technique without the use of an adhesive agent. Samples were made at various thickness reductions (40%, 50%, 60%, and 75%), and their mechanical properties were compared with the monolithic metallic sheet by performing a small punch test. The results showed significant improvements in the specific strengths of the sandwich composites compared with the monolithic material by 26%, 20%, and 39% at the thickness reductions of 50%, 60%, and 75%, respectively. The specific fracture energy of the sandwich composites at thickness reductions of 60% and 75% was higher than the monolithic material by 7% and 20%, respectively. The results showed that the direct adhesion WRB is a promising technique to fabricate a lightweight, metal-polymer sandwich composite panel. (C) 2016 Elsevier B.V. All rights reserved.