Application of the design of experiments procedure to the behaviour of adhesively bonded joints with plastically deformable adherends to enable further understanding of strain rate sensitivity

Abstract

The study presented in this paper was carried out to investigate further the effects of strain rate on the strength of adhesively bonded single lap shear joints. Tests were carried out on two different configurations of adhesively bonded joints that were designed to exhibit different behaviours. In one configuration both adherends were made from a relatively low strength grade of aluminium such that both would exhibit significant plastic deformation prior to adhesive failure. The other configuration used one adherend that was significantly stronger such that only elastic deformation was exhibited prior to failure of the adhesive. The joint specimens were tested at several different strain rates using a servo-hydraulic test machine and the results analysed using statistical methods. To further understand the results Finite Element models of the joints were created using a Cohesive Zone Model to predict damage development and failure in the adhesive. The Design of Experiments procedure was used to study the effects of material parameters relating to both the adherends and the adhesive in the Finite Element models. The results of the testing suggested that the strength of joints formed from two adherends that exhibited plastic deformation prior to failure did not show statistically significant sensitivity to strain rate. Interpretation of the results of the Finite Element analyses suggested that the adherend yield was the main factor influencing failure in the adhesive for joints of this type.

Failure criterion for adhesively bonded joints using Arcan´s experimental method

“…In adhesively bonded joints with higher stiffness adhered (substrate), like proposed in this work, the joint strength is more dependent on adhesive properties than on adhered properties [21] , which emphasizes the possible influence of factors like air bubbles and movement restriction on the observed variation at 45° and 10 mm/min.…”

Versatile Approaches to Engineering and Applied Sciences: Materials and Methods

“…Cohesive Zone Modelling (CZM) has been implemented with great success for the design of bonded joints. Commercial software solvers demonstrated to have enough accuracy to predict impact failure, as stated by several authors such as May et al (2014) and Clarke et al (2013). Araújo et al (2017) presented an industrial study focused on the impact of adhesively bonded joints in the automotive industry.…”