Correlation of Charpy-V notch and different Charpy-U notch impact specimen energies for structural metals

The most common mechanical test to evaluate the fracture resistance of a structural metal is the Charpy-V impact test. Nearly all structural integrity assessment procedures use it. The preferred notch geometry is the V-notch, but other geometries are or have been sometimes used. The U-notch has normally a root radius of 1 mm, compared to the V-notch which has a root radius of 0.25 mm. Even though the V-notch specimen is today the main geometry, many different specimen versions are still being used to some extent. More importantly, vintage data corresponding to something else than V-notch data may be the only information available for older structures, still in use. For such cases, it is imperative to have a correlation between different notch geometries. Here simple correlations for the upper shelf energy and the 35 J/cm2 transition temperatures are developed for four different U-notch geometries. © 2022 Elsevier Ltd