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

A high-weather-resistant hot-rolled h-beam with a yield strength of 450mpa and its heat treatment process

A technology of yield strength and H-shaped steel, which is applied in the field of high-weathering hot-rolled H-shaped steel with a yield strength of 450MPa and its heat treatment process, can solve the problems of unfavorable structural processing, easy brittle fracture, high strength, etc., and achieve good uniformity and comprehensive mechanics Performance, reduction of rolling difficulty and production, effect of reduction of dislocation density

Active Publication Date: 2020-05-19
MAGANG (GROUP) HOLDING CO LTD +1
View PDF9 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Due to the current domestic hot-rolled H-shaped steel production process and equipment limitations, the austenite recrystallization zone and non-recrystallization zone rolling can not achieve large reduction, after rolling, air cooling or water spray cooling is used. After many verifications, only The current domestic hot-rolled H-beam tooling, hot-rolled high-weather-resistant hot-rolled H-beam, its microstructure is basically granular bainite or upper bainite, the product has high strength but poor plasticity and toughness, and the yield strength usually exceeds 800MPa, the tensile strength exceeds 900MPa, and its -40℃KV 2 The average impact energy of the model is only about 15J. When subjected to dynamic load or impact, it is prone to brittle fracture, which seriously affects the service safety of railway wagons and bridges, and is also very unfavorable to structural processing.

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
  • A high-weather-resistant hot-rolled h-beam with a yield strength of 450mpa and its heat treatment process
  • A high-weather-resistant hot-rolled h-beam with a yield strength of 450mpa and its heat treatment process

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0036]A high-weather-resistant hot-rolled H-shaped steel with a yield strength of 450MPa, according to mass percentage (wt%), the melting chemical composition ratio is: C: 0.08, Si: 0.29, Mn: 0.56, P: 0.012, S: 0.009, Cr: 3.10, Ni: 0.40, Cu: 0.42, V: 0.026, Alt: 0.023, and the rest are Fe and other unavoidable impurities.

[0037] The preparation method of the high weather resistance hot-rolled H-shaped steel with a yield strength of 450MPa is as follows:

[0038] Taking the hot-rolled H-shaped steel with a flange thickness of 17mm as an example, the billet is processed by a hot-rolling process: heating temperature 1226 ° C, 2 hours in the furnace, starting rolling temperature 1093 ° C, finishing rolling temperature 907 ° C;

[0039] Then heat treatment by tempering process: heating from cold state at 10°C / s to 680°C, holding for 2h, and air cooling after being out of the furnace.

[0040] The final yield strength of the 450MPa-grade high-weather-resistant hot-rolled H-beam o...

Embodiment 2

[0042] A high-weather-resistant hot-rolled H-shaped steel with a yield strength of 450MPa, according to mass percentage (wt%), the melting chemical composition ratio is: C: 0.06, Si: 0.28, Mn: 0.42, P: 0.010, S: 0.006, Cr: 2.52, Ni: 0.33, Cu: 0.38, V: 0.019, Alt: 0.026, and the rest are Fe and other unavoidable impurities. ,

[0043] The preparation method of the high weather resistance hot-rolled H-shaped steel with a yield strength of 450MPa is as follows:

[0044] Taking the hot-rolled H-shaped steel with a flange thickness of 17mm as an example, the billet is processed by a hot-rolling process: heating temperature 1226 ° C, 2 hours in the furnace, starting rolling temperature 1093 ° C, finishing rolling temperature 907 ° C;

[0045] Then heat treatment by tempering process: heating from the cold state at 6°C / s to 615°C, holding for 2h, and air cooling after being out of the furnace.

[0046] The final yield strength of the 450MPa-grade high-weathering hot-rolled H-beam o...

Embodiment 3

[0048] A high-weather-resistant hot-rolled H-shaped steel with a yield strength of 450MPa, according to mass percentage (wt%), the melting chemical composition ratio is: C: 0.09, Si: 0.36, Mn: 0.61, P: 0.010, S: 0.009, Cr: 2.80, Ni: 0.46, Cu: 0.45, V: 0.033, Alt: 0.036, and the rest are Fe and other unavoidable impurities.

[0049] The preparation method of the high weather resistance hot-rolled H-shaped steel with a yield strength of 450MPa is as follows:

[0050] Taking the hot-rolled H-shaped steel with a flange thickness of 17mm as an example, the billet is processed by a hot-rolling process: heating temperature 1226 ° C, 2 hours in the furnace, starting rolling temperature 1093 ° C, finishing rolling temperature 907 ° C;

[0051] Then heat treatment by tempering process: heating from cold state at 18 °C / s to 700 °C, holding for 2 hours, and air cooling after being out of the furnace.

[0052] The final yield strength of the 450MPa-grade high-weather-resistant hot-rolled ...

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
yield strengthaaaaaaaaaa
yield strengthaaaaaaaaaa
tensile strengthaaaaaaaaaa
Login to View More

Abstract

The invention discloses 450MPa-grade yield strength high-weather-resistance hot-rolled H-shaped steel and a heat treatment technology thereof. The 450MPa-grade yield strength high-weather-resistance hot-rolled H-shaped steel comprises the following chemical compositions of, by weight, 0.06-0.10% of C, 0.20-0.40% of Si, 0.40-0.70% of Mn, no more than 0.035% of P, no more than 0.010% of S, 2.00-3.50% of Cr, 0.30-0.50% of Ni, 0.30-0.50% of Cu, 0.015-0.035% of V, 0.020-0.040% of Alt, and the balance Fe and unavoidable impurities. The heat treatment tempering technology of the 450MPa-grade yield strength high-weather-resistance hot-rolled H-shaped steel comprises the following steps that heating is conducted to 600-700 DEG C at 5-20 DEG C / s, heat preservation is conducted for two hours, and then air cooling is conducted. The yield strength of the high-weather-resistance hot-rolled H-shaped steel obtained through the heat treatment technology exceeds 480 MPa, the tensile strength exceeds 600MPa, and the percentage elongation after fracture exceeds 20%, -40 DEG C KV<2> type impact work is larger than or equal to 65 J, and the good low-temperature impact toughness is achieved.

Description

technical field [0001] The invention belongs to the technical field of metal material production, and in particular relates to a high-weather-resistant hot-rolled H-shaped steel with a yield strength of 450 MPa and a heat treatment process thereof. Background technique [0002] Weather-resistant hot-rolled H-shaped steel is mainly used in railway freight car chassis and bridge structures. With the development of domestic rail transportation to high-speed, heavy-duty, and long-life, it operates in different climate regions, while bridges tend to be large-span and lightweight Development, construction and service environments also cover different climate regions in China. The manufacture of railway wagon chassis and bridge structures urgently needs hot-rolled H-shaped steel with high weather resistance, high strength and high toughness. [0003] In order to meet high weather resistance requirements (relative to Q345B corrosion rate ≤ 30%), hot-rolled H-beams have higher Cr, Ni...

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 Patents(China)
IPC IPC(8): C22C38/02C22C38/04C22C38/42C22C38/46C22C38/06C21D8/02
CPCC21D8/005C21D2211/002C21D2211/005C22C38/002C22C38/02C22C38/04C22C38/06C22C38/42C22C38/46
Inventor 夏勐吴保桥程鼎张卫斌彦井成邢军龚庆华彭林黄琦丁朝晖魏银丹蒲玉梅张步海柏胜
Owner MAGANG (GROUP) HOLDING 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