Penetration of Mild steel sheets by Conical punch

This investigation presented an approach for estimating the energy was during the penetration of a circular thin metal sheet by a conical punch, based on the J-integral R-curve approach to characterizing a material's resistance to fracture. The formula for the estimation of the total work done during the penetration was proposed by using the tear modulus, T. The penetration tests on the circular thin sheets of mild steel, whose thickness were 1.0,2.1 and 3.1mm, and whose diameters were 450mm, were carried out at a quasi-statical speed using conical punches with punch angles of 30 and 45 degree. The effects of plate thickness and punch angle on the plate failure mode, the number of petals, the thickness directional strain ε_z, and the total work done were investigated. The estimated values of the total work done by the proposed formula was found to be in fairly agreement with experimental results.