抄録
This report studies the failure phenomena of ductile thin metal sheets using conical punches and tries to estimate the total work done which is absorbed under penetration. Penetration tests on circular thin sheets of mild steel, at thicknesses of 1.0, 2.1 and 3.1 mm and at a blank diameter of 200 mm, are carried out at a quasi-static punch speed using conical punches. The punch angles are 30, 45, 60 and 90 degrees and the punch nose diameters are 5.5 and 20 mm. The effects of the sheet thickness, the punch angle and thee punch nose diameter on the failure mode of a thin sheet are investigated experimentally. In addition, the authors present formulae for estimation of the energy-absorbing capacity of ductile thin metal sheets under penetration. By comparing the estimated values with the experimetal ones, it is clear that the proposed formulae are valid for assessment of the energy-absorbing capacity of thin sheets, except for the case of large punch angle.
