Strong Tough HSLA Steels Via Processing and Heat Treating of Cu-Ni-Cb and Cu-Ti-B Compositions

Abstract

The paper deals with the development of control-rolled Cu-Ni-Cb HSLA steels with increased section capability for low-temperature environments and Cu-Ti-B HSLA steels for general structural applications as well as for specialized applications requiring quench and temper treatments. Results indicate that based on 2 percent copper additions it is possible to develop HSLA steels with strength level of over 690 MPa with sufficiently low transition temperatures (−40°C to lower than −70°C) and very upper shelf values (170 J to 270 J). In the boron-containing compositions, even in the absence of nickel, strength levels of 480 to 820 MPa with a T. T. of −20°C to lower than −60°C have been realized depending upon the rolling practice and the reheat and quench practice. The practical implications of the study are discussed.