Simplified Evaluation of Brittle Crack Arrest Toughness in Heavy-thick Plate by Combined Small-scale Tests

摘要

To develop a simplified evaluation method for brittle crack arrest toughness in a heavy-thick plate, the correlation between large-scale tests (such as the ESSO test) and small-scale tests (such as the Naval Research Laboratory (NRL) drop-weight test and the Charpy V-notch impact test) was investigated. It was found that the Nil-Ductility Transition Temperature (NDTT) obtained by the NRL drop-weight test at the surface layer and the fracture appearance transition temperature (vTrs) obtained by the Charpy V-notch impact test at the quarter thickness position have a high correlation with brittle crack arrest toughness. A simplified evaluation equation for arrest toughness was suggested by the combination of the results of the small-scale tests. It was confirmed that the developed equation can be applied to various steels independent of the chemical composition and the manufacturing process.