Patents Assigned to AM/NS CALVERT LLC
  • Patent number: 10323307
    Abstract: A steel alloy and process for producing a hot formed component. The process includes providing a steel alloy sheet having a chemical composition (wt %) within a range of 0.3-0.85 C, 1.0-6.0 Mn, 1.0-4.0 Si+Al and the remainder being tramp elements and impurities. The steel alloy sheet is heated to within a temperature range between 700-900° C. for a time between 1-180 seconds and hot formed. Thereafter, the hot formed sheet is cooled to ambient temperature. Then, cooled hot formed sheet is tempered at a temperature between 200-600° C. for a time between 20-3000 seconds and cooled again to ambient temperature. The tempered and cooled sheet has a tensile strength between 1400-2400 MPa and at least 10% elongation to failure, and/or a product of tensile strength times percent elongation to failure of at least 16000 MPa·%.
    Type: Grant
    Filed: July 17, 2015
    Date of Patent: June 18, 2019
    Assignee: AM/NS Calvert LLC
    Inventors: Bertram Wilhelm Ehrhardt, Ranbir Singh Jamwal
  • Patent number: 9493864
    Abstract: A process for producing high strength steel is provided. The process includes providing a steel slab having a chemical composition in weight percent within a range of 0.025-0.07 C, 1.20-1.70 Mn, 0.050-0.085 Nb, 0.022 max Ti, 0.065 max N, 0.0040 max S, 0.10-0.45 Si, 0.070 max P, with the balance being Fe and incidental impurities. The steel slab is soaked within a temperature range of 1150-1230° C., hot rolled using a roughing treatment in order to produce a transfer bar and further hot rolled using a finishing treatment in order to produce hot rolled strip. The hot rolled strip is cooled using a cooling rate between 10-100° C./second (sec) and coiled within a temperature range of 580-400° C. Finally, the coiled hot rolled strip has a yield strength of at least 80 ksi and a DWTT transition temperature equal or less than ?20° C.
    Type: Grant
    Filed: March 14, 2014
    Date of Patent: November 15, 2016
    Assignee: AM/NS Calvert LLC
    Inventors: Bertram Wilhelm Ehrhardt, Chris John Paul Samuel, Ranbir Singh Jamwal, Gerald McGloin, Stanley Wayne Bevans, Markus Wilhelm Forsch, Rudolf Schonenberg
  • Publication number: 20140261903
    Abstract: A bake hardenable steel and a process for manufacture of a bake hardenable steel. Steel alloy slabs with a predefined chemical composition are hot rolled into hot rolled strip. The hot rolled strip is cold rolled and continuously annealed on a continuous annealing line and then rapidly cooled to at least 600° C. using a cooling rate of between 20-100 K/sec, and optionally cooled to at least 140° C. using a cooling rate of between 3-20 K/sec. As such, the cold rolled and annealed sheet is not subjected to an overageing treatment and yet still exhibits excellent and well defined bake hardening values. For example BH2 values between 25 and 45 MPa are exhibited by the low alloy steel grades. In addition, the bake hardeneable steel sheet has a minimum yield strength of 220 MPa and in some instances has a minimum yield strength as high as 380 MPa.
    Type: Application
    Filed: March 17, 2014
    Publication date: September 18, 2014
    Applicant: AM/NS CALVERT LLC
    Inventors: Joseph Frimpong, Bertram Wilhelm Ehrhardt, Stanley Wayne Bevans, Harald Van Bracht
  • Publication number: 20140261915
    Abstract: A process for producing high strength steel is provided. The process includes providing a steel slab having a chemical composition in weight percent within a range of 0.025-0.07 C, 1.20-1.70 Mn, 0.050-0.085 Nb, 0.022 max Ti, 0.065 max N, 0.0040 max S, 0.10-0.45 Si, 0.070 max P, with the balance being Fe and incidental impurities. The steel slab is soaked within a temperature range of 1150-1230° C., hot rolled using a roughing treatment in order to produce a transfer bar and further hot rolled using a finishing treatment in order to produce hot rolled strip. The hot rolled strip is cooled using a cooling rate between 10-100° C./second (sec) and coiled within a temperature range of 580-400° C. Finally, the coiled hot rolled strip has a yield strength of at least 80 ksi and a DWTT transition temperature equal or less than ?20° C.
    Type: Application
    Filed: March 14, 2014
    Publication date: September 18, 2014
    Applicant: AM/NS CALVERT LLC
    Inventors: Bertram Wilhelm Ehrhardt, Chris John Paul Samuel, Ranbir Singh Jamwal, Gerald McGloin, Stanley Wayne Bevans, Markus Wilhelm Forsch, Rudolf Schonenberg