Fracture toughness properties in the transition region of the Eurofer97 tempered martensitic steel

A fracture toughness database obtained on the Eurofer97 steel (25 mm plate, heat 83697) is presented. The material has been tested in the ‘as-received’ condition in the lower transition region at temperatures ranging from 173 K down to 123 K. Sub-sized (0.35T) compact tension specimens, 0.35T C(T), have been used in this study. The database is analyzed in the framework of ASTM E-1921–03 standard. The results indicate that the median toughness–temperature curve of the Eurofer97 is steeper than the master curve for ‘ferritic’ steels used in the ASTM E-1921 framework. This database is also compared with fracture toughness data obtained on different Eurofer97 heats and previously reported in the literature. Modest variations in the reference temperature T0 used to index the fracture toughness–temperature curve were found between the different heats.