Easy-to-weld superfine austenite crystal steel with superhigh intensity and high tenacity and manufacturing method thereof

An austenite grain, ultra-high strength technology, applied in the field of ultra-fine grain steel and its manufacturing, can solve the problems of not involving high-performance steel materials, damaging the welding performance of steel, increasing equipment and process costs, etc.

Inactive Publication Date: 2009-07-15
YANSHAN UNIV
View PDF9 Cites 49 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] 2) It is required to adopt low-temperature rolling and rapid cooling after rolling in the recrystallization zone. Although the corresponding strength level is also achieved and the amount of alloy is reduced, the requirements for metallurgical technology and equipment are harsh, which actually increases equipment and equipment. Process cost
[0007] 3) The carbon content in the steel is required to be high, although it is beneficial to achieve ultra-high strength levels, but it will damage the welding performance of the steel
It can be seen that although the above-mentioned achievements or patents all adopt the quenching treatment method of direct resistance heating or induction heating, none of them involve a variety of steels with ultra-high strength, high toughness, easy welding and ultra-fine austenite grains at the same time. Characteristic high-performance steel material and manufacturing method thereof

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Easy-to-weld superfine austenite crystal steel with superhigh intensity and high tenacity and manufacturing method thereof
  • Easy-to-weld superfine austenite crystal steel with superhigh intensity and high tenacity and manufacturing method thereof
  • Easy-to-weld superfine austenite crystal steel with superhigh intensity and high tenacity and manufacturing method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0054] Invention Steel 1 adopts molten iron deep desulfurization and pre-dephosphorization technology to make S≦0.005 and P≦0.015 in molten iron, and performs top-bottom combined blowing on a 150-ton converter. The chemical composition in the steel meets the requirements in Table 1, and the balance is Fe and unavoidable impurity elements. The molten steel is further cast into a slab with a section of 240mm×1450mm, and then made into a hot-rolled slab with a thickness of 3-12mm on a 2150mm rolling mill. Among them, the main hot continuous rolling production process is: the heating temperature of the slab is 1150-1200°C, the rough rolling start temperature is 1120-1180°C, the rough rolling total reduction is 60-70%, and the rough rolling end temperature is 1000-1000°C. 1050°C. The start temperature of finish rolling is 930-980°C, the total reduction ratio of finish rolling is 30-40%, and the end temperature of finish rolling is 850-920°C. After rolling, adopt laminar flow cool...

Embodiment 2

[0056] Invention Steel 2 selects raw materials with low sulfur and phosphorus content, and uses a 50Kg vacuum furnace for smelting, so that the chemical composition in the steel meets the requirements of Table 1, and the balance is Fe and unavoidable impurity elements. Then use inert gas protection to cast, pour two ingots per furnace, and the average diameter of the ingot is After the ingot riser is cut off, it is forged into bar stock. The main forging process is as follows: the billet is heated at 1150-1200°C, the rough forging start temperature is 1120-1180°C, the rough forging total reduction rate is 60-80%, and the rough forging end temperature is 1000-1050°C. The start temperature of finish forging is 930-980°C, the total reduction rate of finish forging is 20-40%, and the finish temperature of finish forging is 850-950°C. After the forging is air-cooled to room temperature, it is tempered at 520 °C for 10 min. Cut the 1000mm long bar, and use induction heating for...

Embodiment 3

[0058] Invention Steel 3 is smelted in a 500Kg electric furnace, and the raw materials for steelmaking are concentrates with low sulfur and phosphorus contents. After the chemical composition of the molten steel meets the requirements in Table 1, the inert gas protection is used for casting, and one ingot is poured in each furnace, and the size of the ingot is 240×1000mm. After the ingot riser is cut off, it is forged into bar stock. After cross-rolling and piercing, continuous rolling and sizing, the bar is processed into a seamless steel pipe with a diameter of 52 mm and a wall thickness of 4.2 mm. The main process parameters of tube rolling are as follows: the billet is heated at 1200-1250 °C and then cross-rolled and pierced, with a deformation of 60-70%; then the tube is rolled at 1150-1100 °C, and the diameter is reduced under tension at 850-900 °C. The amount of deformation is 30-40%. After the steel pipe is air-cooled to room temperature, it is tempered at 550°C ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
particle sizeaaaaaaaaaa
yield strengthaaaaaaaaaa
tensile strengthaaaaaaaaaa
Login to view more

Abstract

The invention discloses an ultra-thin austenitic grained steel with ultrahigh strength, high toughness and easy welding and a manufacturing method thereof. The chemical compositions of the steel are as follows in terms of weigh percentage: 0.04 to 0.14 of C, 0.50 to 1.75 of Mn, 0.10 to 0.50 of Si, no more than 0.010 of S, no more than 0.012 of P, no more than 0.50 of Ni, no more than 1.00 of Cr, no more than 0,80 of Mo, no more than 0.10 of V, 0.10 to 0.30 of Cu, 0.010 to 0.050 of Al, 0.010 to 0.050 of Ti, no more than 0.050 of Nb, 0.0005 to 0.0020 of B, no more than 0.0090 of (O+N), no more than 0.15 of Pb+Sn+As+Sb+Bi and the balance of Fe and impurities. The equivalent carbon content CEQ (%) is no more than 0.60 and the crack sensitivity index PCM (%) is no more than 0.30. The manufacturing method comprises the following steps: low-temperature short-time tempering pretreatment, short-time heat preservation after extremely fast and integral heating to more than Ac3, then holding the temperature, and extremely fast quenching to the room temperature. The austenitic grain of the steel has the average size of less than or equal to 6.5Mum, the yield strength of more than or equal to 840MPa, the tensile strength of more than or equal to 945MPa and tough-brittle transition temperature of less than or equal to minus 60 DEG C. The method is particularly suitable for heat treatment of working pieces with thin specification.

Description

technical field [0001] The present invention relates to an ultra-fine grain steel and a manufacturing method thereof, in particular to an ultra-fine austenitic grain steel having multiple characteristics such as ultra-high strength, excellent low-temperature toughness, and good weldability, and a manufacturing method thereof. The method can be used in the manufacture of thin-spec high-performance structural parts such as hot-rolled thin plates, thin-walled seamless steel pipes, and thin shaft parts. Background technique [0002] At present, iron and steel materials are still the main body of structural materials, and welding is still the main structural manufacturing process. The development of high-performance iron and steel materials with ultra-high strength, excellent low-temperature toughness, good weldability and other characteristics and their key manufacturing technologies is an important way to meet the long-term safety of modern important structures, reduce self-wei...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C22C38/58C22C38/54C21D1/18B21B37/16
CPCY02P10/20
Inventor 王青峰淡婷
Owner YANSHAN UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap