Effect of stand-off distance and the explosive ratio parameters on the properties of explosively bonded copper-aluminum-copper

The aim of this study was to investigate the influence of stand-off distance and the explosive ratio parameters on metallurgical and mechanical properties of three-layers explosively bonded copper-aluminum-copper interface. To illustrate effects of these two parameters, samples welded with different stand-off distances and explosive ratios. Optical microscopy, scanning electron microscopy, microhardness and tensile-shear strength tests carried out on the samples. The results indicate a suitable joint with proper metallurgical and mechanical properties in copper-aluminum-copper plates. Microscopic images showed the semi unsymmetrical wavy interface with cracks and voids, also by increasing the explosive ratio, locally melted zones was increased at the interfaces. Elemental analysis confirmed the brittle intermetallic compounds at the interface that produce cracks in these areas. Also, the wavelength increased with increasing explosive ratio. Hardness increased near the interfaces due to the severe plastic deformation and increased with increasing the explosive ratio. Tensile-shear test results showed the decrease in bond strength caused by increasing the explosive ratio.