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Abstract
Corrugated Wire Mesh Laminates (CWML) are open cell type cellular structures manufactured by bonding several layers of metallic corrugated wire meshes on top of each other. Due to their open cell structure and the mechanical properties of the parent material, CWML can offer high stiffness and strength per unit weight. Therefore, they have many potential applications where lightweight and high rigidity and strength are required, such as in sandwich constructions in mechanical and aerospace engineering, and orthopaedic implants in biomedical engineering. The main loading in such applications is transverse compression, occasionally accompanied by in-plane shear. This thesis presents an attempt to understand and characterise the behaviour of corrugated wire mesh laminates under transverse compression loading. First, a theoretical model is developed for the CWML using a truss structure to approximate the corrugated wire. Although simplistic, this model is useful in establishing expressions for the relative density, effective transverse stiffness and transverse compressive strength of the CWML. The influences of wire diameter, opening width, and the corrugation angle on these parameters are established. A new method is developed for the fabrication of CWML at a relatively low temperature of 225 degrees Celsius making it significantly simpler and cost effective compared to existing methods. For the first time, a finite element model is developed to numerically simulate the deformation behaviour of CWML under transverse compression and shear loading. The numerical model investigates the effects of nonlinearities such as material nonlinearity, large deformation behaviour, curvature at the tip of the corrugations and friction. Experimental testing is conducted on several samples of single layer, two layer, and four layer wire mesh laminates under transverse compression and separately under shear loading. The test results show considerable scatter probably due to variations in the quality of the bonding in the manufacturing process. The load deflection behaviours of the single and multi layer laminates observed in the tests are compared to those analytically determined by the numerical simulations. Unfortunately, the agreement between the numerical analysis and the experimental results is rather poor; this is attributed to the bends in the wires as they cross over each other in the mesh, which were not modelled in the simulation. The finite element (FE) model, therefore, requires further improvement; nevertheless, it does provide significant insight into aspects that influence the deformation behaviour of CWML.