Investigation of technological factors influencing the strength of bonded Al – alloy

Abstract

Adhesive bonding makes up a significant part of rigid joints of machine elements. The aim of this study was to investigate the contamination effect of moisture and oil on the bond strength of aluminium alloy 2024 T3 bonded by film and liquid adhesives using mechanical and chemical surface preparation methods. Two types of joints were used: homogeneous (Al-Al) and heterogeneous (Al-GFRP) ones. Surface preparation highly increased surface roughness Ra. The surfaces were moistened with deionized water and mineral oil and glued after a constrained time delay (outlife). Tensile shear strength tests of the joints showed higher strength of the chemically prepared surfaces by gluing with film adhesive. Contrarily mechanically prepared surfaces were stronger with liquid adhesive. Film adhesive seemed less sensitive to surface contamination in general.