Abstract: Based on the JWL equation of state of detonation products and Taylor fracture criteria, a model considered the expansion details about energy conversion and fragment initial velocity is derived from conversation of energy. The cylinder tests of three materials, including copper, 45^# steel and 6061 aluminum alloy, driven by TNT explosive are made, and the inflation track and velocity are analyzed. The experimental results show that, by comparing with Gurney formula which is considered only to express the driving ability of the explosion parameter, the proposed model considers the driving factors, inflation process and mechanics function of meta. The result is of pertinence and applicability.

Key words: ordnance science and technology, detonation driven, equation of state, energy conversion, fragment initial velocity