Patent ID: 7842142
Filing Date: 2010-11-30
Classification: C21D,C22C

Abstract:
1. A method for producing a high-strength part, comprising: providing a steel sheet comprising between about 0.05 and 0.55 wt % C, and between about 0.1 to 3 wt % Mn; heating the steel sheet to a temperature between an Ac3 temperature and a melting point in an atmosphere comprising between about 0 and 4% hydrogen, where the atmosphere has a dew point less than about 0° C. or less; initiating a shaping of the steel sheet at a temperature higher than a temperature at which ferrite, pearlite, bainite, and martensite transformations occur; cooling and hardening the steel sheet after shaping in a mold to form the high-strength part having a tensile strength of about 980 MPa or more; post-processing the part, wherein the post-processing comprises shearing the part; and shearing the part again at a distance between about 200 and 2000 μm from a worked end of the part.