Investigations on strength and ductility of base metals and welded joints of steels for power plants at elevated temperatures

Dynamic strain aging can appear at low alloyed ferritic steels and their welded joints. It influences the strength as well as toughness of the steels. It causes a relative maximum of impact energy at temperatures around 300°C. It also causes a distinct dependence of the strain rate on the shape of crack resistance curves. A lower slope of J_R-curves is to be found at higher deformation rates. The technical initiation J_Ic has a relative minimum in the range between 200 and 300°C.