18289606. HIGH-STRENGTH HOT-ROLLED STEEL SHEET AND METHOD FOR MANUFACTURING HIGH-STRENGTH HOT-ROLLED STEEL SHEET simplified abstract (JFE STEEL CORPORATION)
HIGH-STRENGTH HOT-ROLLED STEEL SHEET AND METHOD FOR MANUFACTURING HIGH-STRENGTH HOT-ROLLED STEEL SHEET
Organization Name
Inventor(s)
Hiroshi Hasegawa of Chiyoda-ku, Tokyo (JP)
Hideyuki Kimura of Chiyoda-ku, Tokyo (JP)
HIGH-STRENGTH HOT-ROLLED STEEL SHEET AND METHOD FOR MANUFACTURING HIGH-STRENGTH HOT-ROLLED STEEL SHEET - A simplified explanation of the abstract
This abstract first appeared for US patent application 18289606 titled 'HIGH-STRENGTH HOT-ROLLED STEEL SHEET AND METHOD FOR MANUFACTURING HIGH-STRENGTH HOT-ROLLED STEEL SHEET
The high-strength hot-rolled steel sheet described in the patent application has a specific chemical composition and a unique steel microstructure.
- Main phases of the steel microstructure include 80% to 100% of martensite and bainite in terms of total area fraction.
- An entire area fraction of martensite dispersed in bainite ranges from 2% to 20%.
- Among the dispersed martensite, more than 50% have an orientation difference of 15° or more between the crystal orientations of martensite and adjacent bainite.
- The average aspect ratio of crystal grains near the surface of the steel sheet is 2.0 or less.
Potential Applications: - Automotive industry for lightweight, high-strength components - Construction for durable structures - Aerospace for strong yet lightweight materials
Problems Solved: - Provides a high-strength steel sheet with a unique microstructure - Enhances the mechanical properties of steel products
Benefits: - Improved strength and toughness - Enhanced formability and weldability - Potential for lighter weight designs
Commercial Applications: Title: Advanced High-Strength Steel Sheets for Lightweight Applications This technology can be utilized in the automotive, construction, and aerospace industries to create stronger and lighter components, leading to fuel efficiency and cost savings.
Questions about the technology: 1. How does the unique microstructure of this steel sheet contribute to its high strength? 2. What are the specific benefits of using this high-strength steel sheet in the automotive industry?
Original Abstract Submitted
A high-strength hot-rolled steel sheet according to the present invention has a specific chemical composition and a steel microstructure including, as main phases, 80% to 100% of martensite and bainite in terms of total area fraction. An entire area fraction of the martensite dispersed in the bainite is 2% to 20%. Among the martensite dispersed in the bainite, an area fraction of martensite each having an orientation difference of 15° or more between a crystal orientation of the martensite and a crystal orientation of at least one of bainite adjacent to the martensite is more than 50% relative to the whole martensite dispersed in the bainite. When regions surrounded by boundaries between adjacent crystals having an orientation difference of 15° or more are defined as crystal grains, an average aspect ratio of the crystal grains present in a region extending from a surface of the steel sheet to a depth of 5 μm is 2.0 or less.
