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Explosive form-cladding is a dynamic process, in which plastic deformation of two sheet metals alongwith solid state welding between them is accomplished by single detonation of an explosive charge. The process parameters include (a) the depth to diameter (h/D) ratio of the dies, (b) the mass of the explosive per unit mass of the cladder (c/m ratio) and (c) the density ratio of the (:ladder and backer. An attempt was made to express the rate of success of the explosive form-cladding endeavours in terms of the process parameters.All experiments were open air, contact operations and were schemed using design of experiments. A granular explosive, with a detonation velocily of 280(I m/s, was the energy generator. Aluminium and copper sheets (1.2 mm thick) were cladder plates and low carbon steel sheet (1.2 mm thick) were backer plates. Analysis Of Variance (ANOVA) was employed to evaluate the significance of the parameters and their interactions on the process.Key words : explosive torm-cladding, design of experiments, ANOVA, model, adequacy check. I N T R O D U C T I O NExplosive torm-cladding is a high energy rate material processing technique in which forming and cladding of two sheet metal blanks are accomplished in one step. The shock wave, produced by the detonation of an explosive. travels outwards from the centre to accelerate and detbrm the cladder. The cladder plate is impacted against the backer plate. Both the plates are accelerated, simultaneously, towards the die surface. Plastic deformation of the two plates and the cladding between them is thus accomplished in single detonation [1]. The parameters include (a) the depth to diameter (h/D) ratio of the dies, Co) the mass of explosive per unit mass of cladder plate (e/m ratio) and (c) the density ratio of the cladder and backer plate (p~,~,,,). An attempt was made to formulate a model, enveloping the above parameters, to predict the rate of success of the explosive form-cladding operations. E X P E R I M E N T A L S E T U P DiesTwo hemispherical tool steel dies of 133 mm outer diameter were fabricated Liberal die entrant radius was provided on each die to ensure smooth flow of metals during deformation. A vacuum vent of 2 mm diameter was drilled at the bottom of the (tie. Four 14 mm diameter holes, equispaced on the die annulus, were also drilled. The other ends of the holes were countersunk at the bottom face of the dies to accomodate the bolt heads. The depth of the dies were 19 mm and 62.5 mm and diameters were 95 mm and 125 mm respectively, thus varying the h/D ratio from 0.2 to 0.5. BlanksThe cladder and backer plates were of 1133 mm diameter and 1.2 mm thick. Four 14 mm holes were drilled on the annulus of each, to coincide with the holes drilled on the die. The cladder and backer material composition are