Experimental investigation of explosive forming of aluminum tubes using gas mixture

Explosive forming is one of the novel sheet metal forming processes in which released energy of explosion is reason of forming. Explosive forming using gas mixture is one of the explosive forming processes. In this process, after getting desired pressure in the mixture of two gases, required energy for forming is obtained by combustion in the chamber. In this research, a new method for forming of aluminum tubes by exploding gas mixture (33% oxygen-68% hydrogen) has been investigated. In order to make plastic deformation in AA6063 aluminum tubes under energy of explosion shock, an experimental setup has been designed and fabricated. Using this setup, aluminum tubes have been formed under different loading conditions and the effect of initial gas pressure and location of ignition on forming and suitable production of part in accordance with die configuration have been investigated. Experimental results show that the initial gas pressure of 12bar with mixing ratio of 32%oxygn-68%hydrogen can cause complete forming of tube in accordance with the die configuration. More initial gas pressure leads to bursting of tube before contact die wall. Also middle of tube is best location of ignition to obtain complete forming of tube.