Strain-rate effects on S690QL high strength steel under tensile loading
Ezio Cadoni, Daniele Forni
Abstract
High Strength Steels are increasingly demanded in building constructions, shipbuilding and other industries. Hard impact and explosion are possible hazards for steel structures as high-rise buildings, bridges, ships, off-shores. Present lack of data sets under high strain-rates might be generate uncertainty in structural assessment under severe dynamic events. In this work a comprehensive experimental investigation of the S690QL structural steel under dynamic tensile loading is presented. Round specimens (extracted from inner and outer zone of plate 40 mm thick) 3 mm in diameter and a having gauge length of 5 mm were tested in order to obtain the stress-strain flow data under three different loading regimes, i.e. quasi-static (10−3 s−1), medium (3–30 s−1) and high strain-rates (250–950 s−1). The results indicate that both core and peripheral parts are moderately strain-rate sensitive. High strain-rate results were compared with those of S355 and S960QL steels in similar conditions. Finally, the stress-strain data of both zones were analysed to determine the material parameters of existing widely used constitutive models.