EVALUATION OF THE FRACTURE TOUGHNESS OF HOT-ROLLED LOW-ALLOY Ti-V PLATE STEEL.

The effects of varying finish rolling temperature (FRT) and cooling rate on the mechanical properties of hot rolled plates of an experimental low alloy Ti-V steel were studied. Fracture toughness was evaluated at slow and high deformation rates. The transition temperatures determined by the various tests do not always correlate, therefore it is recommended that fracture toughness be evaluated by both static and dynamic testing. Following a low cooling rate, the best plate properties are obtained at the lowest FRT in the austenite-ferrite range, although delamination at this temperature may be detrimental for specific applications. Higher cooling rates produce higher strength but lower toughness than lower cooling rates in plates with the same FRT.