Abstract    Effects of some important parameters like impactor effects, plug geometry and initiation points on bonding aluminum tubes to aluminum plugs were studied. The impact velocity and dynamic angle between tube and plug should be precisely managed to achieve an optimum bonding condition. A new explosive bonding technique with the use of two material impactors was proposed. Results are especially suitable for using high-speed explosive materials to bond welded parts having dissimilar properties. A welding window was first presented for bonding aluminum tube to aluminum plug with the help of the experimental data. Numerical simulation was then performed to understand the effect of impactor on flat and curved plugs:. However, due to limited data analysis systems used to register explosive welding parameters, it became evident that numerical analysis was necessary. The important findings were, therefore, explosion modeling and fast tube deformation. For low process duration time and fast deformation, the modeling is very difficult. At the same time, numerical analysis with Abaqus software was performed to investigate the bonding conditions. The calculated impact velocity of the tube and the dynamic angle between the tube and the plug were compared with the numerical results under the same conditions. It was shown that the numerical analysis was consistent with the predicted data. Eventually we concluded that in explosive welding, curved plugs were more advantageous than flat plugs. It can be recommended that due to having a connection surface in high-speed explosives, the use of plastic impactors is more favorable than using hypoelastic impactors.

Keywords    Explosive Welding, Impactor, Impulse Loading, Simulation

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