Strength and failure mechanism of single-lap magnesium-basalt fiber metal laminate adhesively bonded joints: Experimental and numerical assessments

Abstract

A quick literature search reveals the significant lack of data and information concerning magnesium-to-magnesium bonded joints as well as fiber-metal laminates (FMLs) made with magnesium alloys. Therefore, a systematic series of experimental and numerical investigations are carried out to assess the performance of single-lap joints mating FML adherends. The primary goal is to better understand the effects of geometrical and material parameters that influence the performance of magnesium-to-magnesium joints. The FML adherends used in this study consist of basalt natural fiber-epoxy laminate sandwiched in between thin sheets of magnesium alloys, which were subsequently adhesively bonded using a room-cured epoxy resin. The effects of two types of surface treatments, namely, “sandblasting” and “sandblasting with resin coating” on the bond strength and failure mechanism of the adhesively bonded joints (ABJs) are investigated. A 3D numerical model developed to simulate the response of the joints subjected to quasi-static lap-shear tests. This model, which accounts for the material and geometrical nonlinearity in the joints, is used to perform a parametric analysis for establishing the optimal overlap bond length. The distributions of the shear and peel stresses in the overlap region and the effects of adhesive thickness on the performance of the joints are systematically examined. The comparison of the experimental data and numerical results confirms the robustness and cost-effectiveness of the numerical model in predicting the response of such single-lap ABJs.

Influence of Plasma Treatment on Surface Characteristics of Aluminum Alloy Sheets and Bonding Performance of Glass Fiber-Reinforced Thermoplastic/Al Composites

“…This greater bonding is attributed to the increased number of contact points and the mechanical interlocking or "hooking" effect created by the rough surface, which can provide a larger interfacial area and greater resistance to interfacial separation. Many theoretical and experimental studies demonstrated the positive correlation between surface roughness and bonding strength [6,7,25,49]. However, the relationship between surface roughness and adhesion strength is not always straightforward and also depends on the chemical nature of the metal surface.…”

“…Various surface treatment methods are available to enhance the adhesion at the metal-composite interface of FMLs. Mechanical methods, such as grit blasting and mechanical abrasion, can increase surface roughness and create a peak-and-valley surface structure, leading to improved initial adhesion and bonding strength [6,7]. Mohamad et al [8] explored the impact of aluminum surface roughness on the interfacial strength between metal and composites in FMLs, concluding that heightened surface roughness enhances bonding strength.…”

Identifying the contributions of constituents to the fracture performance and failure mechanism of fiber metal laminate

“…[1] Various kinds of FMLs can be explored by combing different kinds of metals and fiber-reinforced composites, such as the common aramid fiber reinforced aluminum laminate (Arall), [2] glass fiber reinforced aluminum laminate (Glare), [3] carbon fiber reinforced aluminum laminate (Carall), [4] graphite or carbon fiber reinforced titanium laminate (TiGr), [5] and other new variants. [6][7][8][9][10] In addition to the numerous investigations on mechanical properties from the material point of view, recent investigations have also paid attention to the forming technique [11][12][13] and structural performance of FML, [14][15][16] which were aimed at extending the applications. By far, the most striking of FML is still its excellent damage tolerance, [17] which is the reason that FML can act as a promising candidate in aeronautics.…”