The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 16, 2021
Filed:
Nov. 04, 2015
Baoshan Iron & Steel Co., Ltd., Shanghai, CN;
Zicheng Liu, Shanghai, CN;
Qing Shi, Shanghai, CN;
Baoshan Iron & Steel Co., Ltd., Shanghai, CN;
Abstract
A steel plate having excellent resistance to fatigue crack growth and manufacturing method thereof, wherein the components of the steel plate in weight percentage are: 0.040-0.070% of C, 0.40-0.70% of Si, 1.30-1.60% of Mn, less than or equal to 0.013% of P, less than or equal to 0.003% of S, less than or equal to 0.30% of Cu, less than or equal to 0.30% of Ni, less than or equal to 0.10% of Mo, 0.008-0.018% of Ti, 0.015-0.030% of Nb, less than or equal to 0.0040% of N, 0.0010-0.0040% of Ca, and the balance being Fe and inevitable impurities. By controlling [% C]×[% Si] between 0.022-0.042, {([% C]+3.33[% Nb])×[% Si]}×V/Tbetween 1.15×10˜2.2×10, carrying out a Ca treatment, and Ca/S=1.0-3.0 and (% Ca)×(% S) 0.28≤1.0×10, the optimizing the TMCP process, the finished steel plate has a microstructure which a duplex-phase structure of ferrite+uniformly and dispersedly distributed bainite and has an improved resistance to fatigue crack growth.