NEW TOUGHNESS PARAMETERS FROM TENSILE TEST FOR OPTIMIZING POSTWELD HEAT-TREATMENT OF ALLOY 800 2.25CR-1MO STEEL JOINT/

A simple test procedure for the estimation of two new ductile fracture toughness parameters has been applied for optimising the postweld hea t treatment temperature for the Alloy 800/2.25Cr-1Mo steel dissimilar metal weld joint. The test procedure exploits the conventional tension test at room temperature using smooth round transverse weld specimens to evaluate the new toughness parameters for the weakest region of th e joint. It is demonstrated that the optimum postweld heat treatment t emperature determined via this new approach is identical to that deter mined from a previous investigation where the conventional method of c orrelating the microstructure and microhardness profiles with the conv entional tensile properties at 773 K had been used.