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The mechanical performance of joints for any engineering applications requires accurate characterization of joint interfaces. This paper presents a simplified experimental procedure to estimate the cohesive zone model (CZM) parameters for predicting the interface failure of adhesively bonded joints subjected to mode I (opening) and mode II (shear) loading. The novelty of this procedure lies in predicting all CZM parameters—cohesive stiffness, strength, and cohesive energy (fracture toughness), of the bonded interface using one common experimental setup. It is observed that the cohesive strength and cohesive energy in shear loading are approximately 3.8 and 11.6 times, respectively, compared to the opening loading condition. Employing a triangular cohesive law, the CZM parameters are combined with appropriate damage initiation (quadratic stress) and evolution (power law) criteria. The proposed methodology is verified against experimental load–displacement responses of the bonded interface under mixed‐mode I/II (opening/shear) loading across a wide range of mode mixity (α = 0°, 15°, 30°, 45°, 60°, 75°, and 90°). The maximum error between the experimental and the numerical peak load is 5.11%. The acceptable agreement between the numerical and experimental results confirms the effectiveness of this method in investigating interface fracture in adhesively bonded joints under different loading conditions. [ABSTRACT FROM AUTHOR]

Electric Discharge Machining (EDM) is a prominent technique for producing components with complex geometry and intricate shapes. However, productivity depends on the selection of optimal input variables. This research investigates EDM and Near-Dry EDM (NDEDM) on AA7050 hybrid composites, exploring the impact of tool materials, Al2O3 powder concentration, and dielectric fluids on Material Removal Rate (MRR) and Surface Roughness (Ra). NDEDM offers a higher MRR due to localized heating and energy concentration, while hydrocarbon oil EDM provides lower Ra due to cooling and lubrication. Tool material properties, thermal conductivity and bonding strength, affect MRR and TWR. Aluminum composite tools via stir casting display a strong bonding interface, leading to efficient energy transfer and higher MRR, while copper composite tools via friction stir processing exhibit weaker bonding, potentially reducing MRR. Hydrocarbon oil significantly lowers TWR due to effective lubrication and cooling, while near dry EDM results in slightly higher TWR. Al2O3 powder enhances MRR, with an optimal concentration of 1 g/l, while higher concentrations hinder MRR. The presence of Al2O3 powder enhanced the surface quality by reducing the size of the recast layers and producing a smoother surface. Globules, craters, microcracks, pock marks and re-casted layers are the noticeable features spotted on the surface. The results were optimized using the TOPSIS optimization technique and process parameters 32 A current, 30 µs Ton, 3 mm gap distance machined under 3 g/l Al2O3 incorporated hydrocarbon oil dielectric medium using copper composites tool proffers optimal machining performance.

AA7050 aluminium alloy used for the main landing gear link was reinforced with SiC particles utilizing stir casting and uniform dispersion of reinforced particles was analyzed through SEM with EDS mapping. Wear test were performed on pin on disc apparatus by varying the process parameters and experimental runs were designed using response surface methodology. The influence of SiC particles on wear resistance at high temperatures was explored and the findings led to the development of a novel wear equation. The hardness of composites increased due to impediments of dislocation movement, and it declines with an increase in temperature owing to a reduction of Pierls stresses. The formation of a Mechanically Mixed Layer (MML) enhances wear resistance with the inclusion of reinforced particles, and the breakdown of this layer swifts the wear from moderate to severe. The mode of wear was a combination of shearing and abrasive at room temperature, shearing and adhesive until the temperature 200ᵒC, and plastic deformation when the temperature exceeded 200 °C, which was confirmed by worn surface morphology.