Method for producing a strain aging treatment methods and high-strength steel structural members

摘要

PROBLEM TO BE SOLVED: To provide a strain aging treatment method for a steel plate by which high strain aging hardening is obtained and the degradation in ductility after the strain aging hardening is reduced.;SOLUTION: The plate which contains 0.01 to 0.15% C, ≤2.0% Si, ≤3.0% Mn, and one or two kinds of Nb and Mo, and is regulated in P, S, Al, and to appropriate amounts is subjected, as a prestrain, to a predeformation treatment of imparting a plastic strain 5% and a heat treatment so as to maintain T(20+log t), i.e., parameters of a heat treatment temperature T (K) and heat treatment time t (s) within a range of (11,000+650Mn+2,800Mo+9,000Nb) to (14,000+650Mn+2,800Mo+9,000Nb). As a result, an increase in the tensile strength above 150 MPa can be obtained without excessively degrading the ductility after the strain aging treatment.;COPYRIGHT: (C)2006,JPO&NCIPI