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In adhesive joints used in several industrial applications, the adherends' bonding is made using an adhesive, which is usually an epoxy resin. However, since these adhesives are derived from petroleum fractions, they are harmful to the environment, due to the pollutants produced both during their manufacture and subsequent use. Thus, in recent years, effective steps have been made to replace these adhesives with ecological (green) ones. The present work focuses on the study of aluminum A1050 joints bonded with a green adhesive; the study also involves the electrochemical anodization method applied to adherends for nano-functionalization. The nanostructured aluminum adherends allow the formation of an expanded surface area for adhesion, compared to the non-anodized adherends. For comparison reasons, two different adhesives (Araldite LY1564 and Green Super Sap) were used. In addition, for the same reasons, both anodized and non-anodized aluminum adherends were joined with both types of adhesives. The lap joints were subsequently tested under both shear-tension and three-point bending conditions. The major findings were that aluminum A1050 anodization in all cases resulted in shear strength enhancement of the joints, while joints with both aluminum anodized and non-anodized adherends and bonded with the eco-friendly adhesive showed a superior shear behavior as compared to the respective joints bonded with Araldite adhesive. [ABSTRACT FROM AUTHOR]

Single-lap joints (SLJs) with similar and dissimilar adherends are extensively used in industrial applications. This paper aims to investigate the interfacial mechanical behavior of SLJs subjected to dynamic loading. The shear-lag model is employed to predict the mechanical behavior of SLJs. The analytical expressions of the interfacial slip, normal stress in the adherends and interfacial shear stress are derived for the SLJs with similar adherends by using the method of separation of variables. The Laplace transform method is applied to numerically simulate the dynamic response of SLJs with dissimilar adherends. Results obtained from the finite element simulation are consistent well with the predictive model. It is found that the more unbalanced the SLJ is, the more non-uniform distribution of interfacial stress is, thus reducing the load-bearing capacity of the SLJ. This inspires us to rationally design a balanced joint to improve the load-bearing capacity. While the emphasis of the present study is on the mechanical behavior of SLJs, the analytical model is equally applicable to the interface analysis of other structures (e.g. concrete-steel bar, fiber-matrix in the composites, etc.). Furthermore, this theoretical method can be also simplified to explain the stress transfer subjected to the (quasi-)static loading with approximately zero density or zero loading speed in the governing equation. [ABSTRACT FROM AUTHOR]