The Double-Notched (V-V) Bar Tension-Bending Test

CIM Bulletin, 1961

During recent studies concerning the effects that various surface treatments, surface imperfections, locked in residual stresses and metallurgical and geometrical notches have upon the mechanical behaviour of metals and, in particular, upon their ten~ sion-bending characteristics under impact loads, it became apparent that specially developed methods and samples would be of great assistance in determining the desired data. This paper describes and discusses a number of different types of doublenotched tension-bending impact samples which have been considered and examined for this purpose. The types most suitable for exploratory investigations are proposed for application in the study of the _behavio1:1r of metals, their welds, and, m ?articular, their surfaces, when subJected to various notch-severities, surface imperfections, strain rates, temperatures, and constrained states of stress (i.e. the relations of the thre.e principal stresses). It is expected that the proposed double-notched tension-bending samples and the proposed test methods will also contribute toward further understanding of the cold brittle behaviour and the notch-sensitivities of metals. The possibilities of introducing the so-called impact notch-sensitivity index and l'elative impact notch sensitivity of metals are discussed. Data obtained on double-notched (V-V) square and flat impact samples are also discussed. The ten sion-bending characteristics of as-cast asrolled, and as-machined surfaces' are examined and analyzed.
Keywords: Ductility of Steels, EDGE, Fracture of Metals, samples, stress concentration, energy, Fracture, Fractures, Impact, Impacts, metals, test, Tests