DEVELOPMENT OF ADVANCED COPPER PRECIPITATION STRENGTHENED HSLA STEELSAND MATCHING HSLA ELECTRODES

The study deals with the relationship between microstructures and prop erties of base plate, HAZ and weld metal, as influenced by alloying el ements in copper precipitation strengthened HSLA and to determine its transformation kinetics. Instrumented Charpy has been used to characte rize the toughness. Microstructures have been studied through optical and transmission electron microscopy. Fractography; including oblique section metallography, has: been used to relate the fracture morpholog y to the variations in the nature of transformation microstructures. P otential base plate and weld compositions giving strength level of ove r 690 MPa with good toughness have been identified.