Abstract: A medium heavy alloy (MHA) and a fabrication method thereof are disclosed. The MHA includes a composition designed and processed such that the MHA has properties comprising a tensile strength of about 1527 MPa, a proof strength of about 1337 MPa, and an impact toughness of about 180 J, when the MHA is forged, and the tensile strength of about 1746 MPa, the proof strength of about 1571 MPa, and the impact toughness of about 55 J, when the MHA is agedly treated. The method includes providing a composition designed according to design specifications of the MHA; forming a cast alloy from the composition by a metallurgy process; and forged the cast alloy at a first temperature to form the MHA having properties that are the design specifications.

Abstract: A novel medium heavy alloy (MHA) a composition designed and processed such that the MHA has properties comprising a tensile strength of about 1527 MPa, a proof strength of about 1337 MPa, and an impact toughness of about 180 J, when the MHA is forged, and the tensile strength of about 1746 MPa, the proof strength of about 1571 MPa, and the impact toughness of about 55 J, when the MHA is agedly treated. The superior strength-toughness is attributed to the face-centered cubic matrix and/or the nano-sized secondary phases. The superior dynamic performance is attributed to the widening of adiabatic shear bands.

Abstract: An ultra-high strength steel (UHSS) includes a composition designed and processed such that the UHSS has properties comprising a tensile strength of about 2020 MPa, a yield strength of about 1781 MPa and a fracture toughness of about 105 MPa·m1/2. The composition incudes Co no more than 8 wt % of the UHSS. The excellent mechanical performance of the UHSS is achieved by nanoscale ?-NiAl and M2C precipitates. The strength and toughness of the UHSS are comparable to those of the commercially used Aermet100 and M54 steels, while the cost of the UHSS is extremely low because of low Ni—Co concentration. This notable cost advantage makes the novel UHSS very competitive for potentially broad applications as structural components in the field of aerospace.

Abstract: A novel medium heavy alloy (MHA) a composition designed and processed such that the MHA has properties comprising a tensile strength of about 1527 MPa, a proof strength of about 1337 MPa, and an impact toughness of about 180 J, when the MHA is forged, and the tensile strength of about 1746 MPa, the proof strength of about 1571 MPa, and the impact toughness of about 55 J, when the MHA is agedly treated. The superior strength-toughness is attributed to the face-centered cubic matrix and/or the nano-sized secondary phases. The superior dynamic performance is attributed to the widening of adiabatic shear bands.