Tensile strength of sheet materials under impact loading

Test procedures are described and strength and plasticity results are presented for a 1.0-mm mild sheet steel and a 0.75-mm D16T high-strength aluminum alloy investigated under impact loading. The experimental investigations include tensile tests of sheet metal specimens with a short test portion and symmetric sharp edge notches. As is shown, the switch from static to impact loading over the range of tensile rates under study is accompanied by variations in the strength and plasticity of the tested metals. The region of residual strains near a sharp notch (determining the area of fracture initiation), formed as the result of tensile loads, is characterized by reduced maximum strains and a smaller length in the longitudinal direction. With distance from the boundary of the initial notch, the region of residual strains becomes extended. © 2000 Plenum Publishing Corporation.