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:
Nov. 30, 2021
Filed:
Apr. 12, 2018
Posco, Pohang-si, KR;
Postech Academy-industry Foundation, Pohang-si, KR;
Sung-Hak Lee, Pohang-si, KR;
Kyoo-young Lee, Gwangyang-si, KR;
Joo-Hyun Ryu, Gwangyang-si, KR;
Sea-Woong Lee, Gwangyang-si, KR;
Seok-Su Sohn, Ulsan, KR;
Hyung-Soo Lee, Pohang-si, KR;
Min-Chul Jo, Pohang-si, KR;
POSCO, Pohang-si, KR;
POSTECH ACADEMY-INDUSTRY FOUNDATION, Pohang-si, KR;
Abstract
Provided is a hot rolled steel sheet having excellent strength and elongation. The hot rolled steel sheet contains, by wt %: carbon (C): 0.05% or more and less than 0.4%, manganese (Mn): 10% to 15%, aluminum (Al): 2% or less, silicon (Si): 0.1 to 2%, molybdenum (Mo): 0.5% or less (excluding 0), vanadium (V): 0.5% or less (excluding 0), phosphorus (P): 0.01% or less, sulfur (S): 0.01% or less, and a remainder of iron (Fe) and inevitable impurities. The hot rolled steel sheet has a microstructure of the hot rolled steel sheet containing, by area %, tempered martensite: 50% to 70%, secondary martensite: 20% or less (excluding 0), epsilon martensite: 2% or less (excluding 0), and retained austenite: 8% to 30%. The hot rolled steel sheet has a tensile strength of at least 1500 MPa, a yield strength of at least 900 MPa and elongation of at least 20%.