The Variation of the Notch Effect with the Variation of Notch Inclination Angle : Impact and Tension Experiment for the Rod Specimen with a V Groove

Abstract

The angle φ between the center line of V-groove and the axis of a rod specimen was called the notch inclination angle, and the variations of notch strengths of mild steels with the variation of φ were studied at room temperature. In impact tensile experiment, the impact strength varied scarcely with φ when φ was near 90°, but it varied suddenly when φ was near φ_s+20°, where φ_s, is an angle corresponding to a shoulder fillet. In static tension experiment, although the notch strengthening appeared at breaking load, the relation between actual breaking stress and φ was similar to that of impact strength qualitatively. Yield strength decreased linearly with the increase of φ when φ was not so close to φ_s. The variation of the elongation percentage and of the contraction percentage of area corresponded to the variation of the impact strength and of the breaking stress, respectively.