Analysis of adhesively bonded joints exposed to low temperatures

Abstract

This thesis is an analysis of the mechanical properties of bulk adhesive and the behaviour of adhesively bonded single lap joints at room temperature and sub-zero temperatures. The process of making test specimens and performing tests in order to assess the tensile, shear and compressive properties of the bulk adhesive, was followed by extensive numerical modelling of the Iosipescu shear test with the LS-DYNA finite element software to develop and verify the adhesive material model on coupon level. Different measurement methods, e.g. strain gauges and digital image correlation (DIC), were used to obtain accurate strains in the initial linear elastic part of the stress-strain curve and in the yield range for all test temperatures. Single lap joints of aluminium-aluminium and composite-composite adherends were tested to obtain failure loads at room temperature and sub-zero temperatures. Finally, the single lap joints were modelled numerically. The failure loads of single lap joints for aluminium-aluminium adherend single lap joints, were predicted well using the established adhesive material model.