Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Production method for low-yield-ratio high-strength medium-thickness steel plate

A production method and technology of low yield ratio, applied in the field of production of high-strength medium-thick steel plates with low yield ratio, can solve the problems of less application of low-carbon steel, achieve cost saving, short tempering time, and lower yield ratio Effect

Inactive Publication Date: 2017-12-08
HUNAN VALIN XIANGTAN IRON & STEEL CO LTD
View PDF2 Cites 11 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Reducing the yield ratio of the material requires the introduction of multi-phase structure. The more common method is to obtain a certain amount of ferrite soft phase structure through off-line two-phase zone quenching treatment. This technology is more effective in high Ni steel and high Mn steel. Common, but rarely used in the production of low carbon steel

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
  • Production method for low-yield-ratio high-strength medium-thickness steel plate
  • Production method for low-yield-ratio high-strength medium-thickness steel plate
  • Production method for low-yield-ratio high-strength medium-thickness steel plate

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] Embodiment one: the rolling of 25mm thick steel plate

[0021] The smelting composition of low alloy plate steel is C= 0.07, Si=0.3, Mn=1.56, Cr= 0.33, Nb= 0.04, Ti= 0.016, Mo= 0.15, B= 0.0005, P= 0.011, S= 0.002, The balance is Fe and unavoidable impurities, carbon equivalent CEQ = 0.43, cold crack sensitivity index Pcm = 0.19. After smelting, it is made into a continuous casting slab with a thickness of 260mm. Process steps include:

[0022] (1) Rolling process: After the continuous casting slab is heated by the heating furnace, the tapping temperature is 1180 o C, the thickness of the intermediate billet after 7 passes of rough rolling is 80mm, the reduction rate of the last three passes of rough rolling is above 20%, and the starting temperature of finish rolling is 935 o C, open and cold temperature is 800 o C, after online quenching, the red temperature is 440 o C with a cooling rate of 35 o C / s, rolled into a steel plate with a thickness of 25mm.

[0023] ...

Embodiment 2

[0027] Embodiment two: the rolling of 40mm thick steel plate

[0028]The smelting composition of low alloy plate steel is C 0.08, Si 0.28, Mn 1.61, Cr 0.31, Nb 0.045, Ti0.018, Mo 0.17, B 0.0008, P 0.013, S 0.002, the balance is Fe and unavoidable acrobatics Elements, carbon equivalent CEQ0.43, cold crack sensitivity index Pcm 0.19. After smelting, it is made into a continuous casting slab with a thickness of 260mm. Process steps include:

[0029] (1) Rolling process: After the continuous casting slab is heated by the heating furnace, the tapping temperature is 1190 o C, the thickness of the intermediate billet after 7 passes of rough rolling is 130mm, the reduction ratio of the last three passes of rough rolling is above 20%, and the starting temperature of finish rolling is 918 o C, open cold temperature is 785 o C, after online quenching, the red temperature is 320 o C with a cooling rate of 30 o C / s, rolled into a steel plate with a thickness of 40mm.

[0030] (2) He...

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
thicknessaaaaaaaaaa
yield strengthaaaaaaaaaa
yield strengthaaaaaaaaaa
Login to View More

Abstract

The invention discloses a production method of a low-yield ratio high-strength medium-thick steel plate. The chemical composition mass percentage of the steel is C=0.06-0.09, Si=0.2-0.4, Mn=1.3-1.8, Al=0.02-0.05, Cr=0.30~0.40, Nb≤0.05, Ti=0.015~0.025, Mo≤0.30, B≤0.0010, P<0.02, S<0.005, CEQ<0.45, Pcm<0.22, the process steps include rolling and heat treatment. The method of the present invention is used for rolling low-yield ratio high-strength medium-thick steel plates, especially high-strength steel medium-thick plates with a yield strength of 550 MPa for construction machinery, and finally obtains tempered strips through quenching and tempering process or TMCP+tempering process. The plate with bainite structure has a yield strength of more than 550MPa, a tensile strength of more than 680MPa, a yield ratio of less than 0.9, an elongation after fracture of more than 17%, and a full-thickness V-notch Charpy impact energy of more than 140J at -20°C. . And excellent performance after welding.

Description

technical field [0001] The invention belongs to the technical field of steelmaking, and relates to a method for producing medium-thick steel plates with low yield ratio and high strength. Background technique [0002] In the field of high-end equipment manufacturing, the lightweight of complete sets of construction machinery equipment is the key breakthrough direction. The application of high-strength steel to key operating components such as booms and underframes and main load-bearing components determines the performance of large-scale construction machinery and is also the key to lightweight. Under the extreme working conditions of ultra-long and heavy loads, there are also high requirements for steel plate shape, product mechanical properties, cold bending properties, welding, fatigue properties, etc. With the development of large-scale equipment manufacturing, in addition to improving the weight reduction of materials, it is also necessary for materials to have a bette...

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): C22C38/02C22C38/04C22C38/06C22C38/38C22C38/26C22C38/28C22C38/22C22C38/32B21C37/02C21D8/02
CPCC22C38/02B21C37/02C21D8/0205C21D8/0221C21D8/0247C21D2211/002C21D2211/008C22C38/04C22C38/06C22C38/22C22C38/26C22C38/28C22C38/32C22C38/38
Inventor 周文浩张青学李玉路郑健孙小平刘丹罗登
Owner HUNAN VALIN XIANGTAN IRON & STEEL CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com