Adhesion Strength of Al/Epoxy Resin Interface over a Wide Range of Loading Rates

Akio Yonezu,Kohei Kanamori,D.A Cendón Franco,Yoshikatsu Kimoto,Hiroyuki Yamada,F Gálvez Díaz-Rubio

doi:10.1051/epjconf/202125001003

Abstract

This study evaluated the interfacial adhesive strength between aluminium alloy and epoxy resin (Al/epoxy resin) over a wide range of strain rates (loading rates). We conducted three types of tests with different loading rate, i.e., a quasi-static tensile test for the range of lower loading rate, a Split Hopkinson Bar (SHB) for the range of middle loading rate, and Laser Shock Adhesion Test (LaSAT) for the range of higher loading rate. LaSAT is a unique test of adhesion evaluation, since laser induced shock wave is employed to lead interfacial fracture. In parallel, finite element method (FEM) is conducted in order to calculate stress distribution at the interface during LaSAT. As a result, it was found that the interface between the aluminium alloy and the epoxy resin interface shows significant loading rate dependency of the adhesion strength and this tendency is very similar to that of bulk epoxy materials.

Highlights

Adhesive bonding with a polymer material has various advantages such as significantly reduced stress concentration and higher strength to weight ratio of component
It is expected that the quasi-static test, Split Hopkinson Bar (SHB) test and Laser Shock Adhesion Test (LaSAT) can be used to evaluate the interfacial strength over a wide range of loading rates
During LaSAT, the delamination was detected by observing the interface from the epoxy resin surface using a microscope

Summary

Introduction

Adhesive bonding with a polymer material has various advantages such as significantly reduced stress concentration and higher strength to weight ratio of component Such a bonding method has been widely used in various engineering components. Deformation and fracture of such a bulk polymer including resin adhesive are well known to significantly depend on loading rate (i.e., strain rate sensitivity: SRS) [1]. It is expected that the quasi-static test, SHB test and LaSAT can be used to evaluate the interfacial strength over a wide range of loading rates. This information will be useful for the design of adhesives under various load factors. A comparison of the results of the quasi-static tensile test, SHB test and LaSAT was made to discuss SRS of adhesion strength

Methods

Results

Conclusion