Study on explosive welding of Cu/steel composite pipe under local water environment

Abstract

In order to improve the energy utilization rate and the bond quality of explosive welding, the local water environment method is used in present study.In this paper, several groups of high-quality Cu/Steel explosive composite pipes are prepared under local water environment. Optical microscope and mechanical property tests are conducted to analyze samples microstructure and mechanical properties. The results show that the waveform dimension of Cu/Steel bonding interface has a positive correlation with explosive layer thickness, and the miniature wavy bonding interface with the highest bonding quality is obtained by using the local water environment method. Compared with the traditional charge method, the consumption of explosives for the local water environment charge method is decreased about 60 % in the same case of experimental conditions. The local water enviroment method solves the problem of ablation damage at the contact surface between metal and explosives, and effectively reduces the diameter expansion phenomenon and end damage caused by boundary effect in the welding process. Through mechanical property tests, it was found that the yield strengths and compressive strengths of Cu/Steel specimens which created by the local water environment method are positively correlated with the explosive thickness. K E Y W O R D S bimetallic composite pipe, explosive welding, local water environment, microstructure