Bumper beam making process
OwnerBrand Bronsema, Jeffrey A. Anderson +1inventors
InventorsBrand Bronsema, Jeffrey A. Anderson, John J. Kary
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Abstract
A bumper beam for vehicles is formed from cold-rolled sheet steel having an initial tensile strength of approximately 70 ksi. The steel sheet is roll formed in a desired cross-section and swept into a curvature corresponding to the vehicle requirements before the steel sheet is heat treated by induction heat and quenched to provide a bumper beam having a tensile strength from 100 ksi up to approximately 260 ksi.
Claims18
A method for forming a bumper beam for a vehicle comprising the steps in the sequence set fourth:
- feeding a steel sheet from a coil along a pathways wherein the sheet is made of a sheet material having a tensile strength less than 80 ksi and a yield strength between 50-60 ksi;
- feeding the steel sheet through a roll mill to shape the cross-sectional area of the steel sheet into a bumper beam form;
- hardening the steel sheet by heat treating the steel sheet, then quenching the steel sheet to provide a steel sheet having a yield strength greater than 80 ksi and a tensile strength greater than 100 ksi and then cutting the steel at specified lengths to provide completed bumper beams.
A method for forming a bumper beam for a vehicle, comprising the steps in the sequence set forth:
- feeding a continuous steel sheet from a coil along a conveyor assembly, wherein the steel sheet comprises a material of carbon, manganese and columbium and having a yield strength between 50-60 ksi, a tensile strength less than 80 ksi, and a thickness between 0.030 and 0.070 inches;
- passing said steel sheet through a punch press to form through slots therein;
- feeding the steel sheet through a roll mill to shape the cross-sectional area of the steel sheet into a bumper beam form;
- sweeping the steel sheet into a specified curvature;
- feeding said swept steel sheet into an enclosed chamber filled with inert gas and having a heat treatment means and quenching means therein;
- heat treating the steel sheet by applying current along the surface of the steel sheet to a temperature range of 1500.degree. F.-2000.degree. F. at a rate of about 1000.degree. F./scc for about two seconds;
- and
- then quenching said steel sheet by quickly immersing the steel sheet in a water solution having a temperature range approximately 70.degree. F.-150.degree. F. to decrease the temperature of the steel sheet at a rate of about 1000.degree. F./sec to produce martensite.
A method for forming a bumper beam far a vehicle comprising the steps in the sequence set fourth:
- feeding a steel sheet from a coil along a pathway;
- feeding the steel sheet through a roll mill to shape the cross-sectional area of the steel sheet into a bumper beam form;
- hardening the steel sheet by heat treating the steel sheet, then quenching the steel sheet to provide a steel sheet having a yield strength greater than 80 ksi and a tensile strength greater than 100 ksi and then cutting the steel at specified lengths to provide completed bumper beams.
Dependencies are inferred from the claim text.