The effect of certain electrical parameters on the forming of flat circular aluminium sheet specimens clamped at their periphery and formed by means of the underwater spark discharge process as described in a previous paper (40) is extended to cover a number of different materials. Experimental observations on the effect of stand-off distance and material thickness on deformation and deflection are included and the speed of movement during the deflection of specimens of different materials is compared. The variation with polar deflection of strain at a particular radius is presented and the nature of the discharge current is also discussed.
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