Impact of temperature on shear strength of single lap Al-Cu bimetallic joint

The paper presents the results of experimental investigations concerning the mechanical properties of aluminium-copper bimetal (Al-Cu) obtained by rolling. The basic mechanical properties of Al-Cu bimetal were determined, anisotropy of mechanical properties was examined, and hardening process was analysed and described. The analysis was also related to each component (layer) of bimetal, for which similar tests were conducted. The essential studies of aluminium-copper bimetal included shear strength tests of single lap joint under uniaxial tension. The tests analysed the effect of temperature of annealing and time on the maximum values of shear stresses (average), which occurred in the course of shearing of the adhesive layer connecting the components of bimetal. Microanalysis of the chemical composition at the border of phase separation was carried out, and thickness of diffusion layer generated at different temperature conditions was measured. The mechanism of joints failure was analysed, depending on the influence of temperature factors. It was found that the intermetallic zone was formed at the boundary of bimetal phase joint during structural changes. This zone was responsible for the change of mechanical properties of bimetallic lap joint and had a significant effect on its operating ability. (C) 2012 Elsevier Ltd. All rights reserved.