High-toughness hot-rolled medium manganese steel with strength-ductility balance greater than 60 GPa.% and preparation method

A technology of tough medium manganese steel and strong plastic product is applied in the field of hot rolled medium manganese steel and its preparation. The effect of increasing the austenite content

Active Publication Date: 2019-04-23
UNIV OF SCI & TECH BEIJING
View PDF2 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] High-manganese twinning-induced plasticity (TWIP) steel and medium-manganese transformation-induced plasticity (TRIP) steel are the dominant steel types of the third generation of advanced high-strength steels due to their high strength and high formability. However, high-manganese steels have smelting alloy losses. And surface oxidation of rolling plate, etc., its application is limited

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
  • High-toughness hot-rolled medium manganese steel with strength-ductility balance greater than 60 GPa.% and preparation method
  • High-toughness hot-rolled medium manganese steel with strength-ductility balance greater than 60 GPa.% and preparation method
  • High-toughness hot-rolled medium manganese steel with strength-ductility balance greater than 60 GPa.% and preparation method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0022] The chemical composition of steel is: C: 0.40%, Mn: 6.25%, Al: 2.28%, Nb: 0.027%, Si: 0.074%, P: <0.005%, S: 0.011%, and the balance is Fe and unavoidable impurities. After the above ingredients were smelted in a vacuum induction melting furnace for 40 minutes, they were cold-rolled in air to room temperature to obtain steel ingots, heated to 1150°C for 2 hours, and forged into 60×45mm forging billets. The final forging temperature was controlled above 900°C, and air-cooled to room temperature.

[0023] In the laboratory Hot rolling is carried out on a four-roller single-stand reversible hot rolling mill. The forging billet is heated to 1200°C and held for 1.5h. After 5 passes, it is hot-rolled into a steel plate with a thickness of 3mm. The starting rolling temperature is 1150°C and the final rolling temperature is not lower than 900°C, water cooled to 430°C and air cooled to room temperature.

[0024] The hot-rolled steel plate was annealed in the two-phase zone i...

Embodiment 2

[0027] The chemical composition, smelting, forging, and hot-rolling processes of the steel are the same as those in Example 1, except that the annealing process in the two-phase zone is to keep the temperature at 725°C for 20 minutes, and then air-cool to room temperature.

[0028] Perform related performance tests on the hot-rolled medium-manganese steel prepared in this example, and process the heat-treated steel plate into a standard tensile sample according to GB / T228-2002 "Metallic Materials Tensile Test Method at Room Temperature", and the tensile speed is fixed at 2mm / min. The results of mechanical properties are shown in Table 1, and the engineering stress-strain curve is shown in figure 1 As shown, the SEM structure morphology is as figure 2 As shown in (b), the XRD characterization results are as follows image 3 shown. It can be seen that the austenite content of the hot-rolled medium-manganese steel after annealing in the two-phase zone is 76%, the tensile str...

Embodiment 3

[0030] The chemical composition of the steel is: C: 0.39%, Mn: 6.08%, Al: 2.31%, Si: 0.031%, P: <0.005%, S: 0.011%, and the balance is Fe and unavoidable impurities . The above components are smelted and cast into steel ingots in a vacuum induction furnace. The steel ingots are heated to 1150°C for 2 hours, forged into 60×45mm forging billets, and air-cooled to room temperature.

[0031] Heat the forging billet to 1200°C for 1.5h, and hot-roll it into a steel plate with a thickness of 3mm after 5 passes.

[0032]The hot-rolled steel plate was annealed in the two-phase zone in a heating furnace, kept at 700°C for 180min, and air-cooled to room temperature.

[0033] Relevant performance tests were carried out on the hot-rolled medium-manganese steel prepared in this example, and the tensile test was carried out according to GB / T228-2002 "Metal Materials Tensile Test Method at Room Temperature". The results of mechanical properties are shown in Table 1, and the engineering stre...

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
tensile strengthaaaaaaaaaa
tensile strengthaaaaaaaaaa
tensile strengthaaaaaaaaaa
Login to view more

Abstract

The invention discloses high-toughness hot-rolled medium manganese steel with strength-ductility balance greater than 60 GPa.% and a preparation method, and belongs to the field of high-toughness automobile steel. The steel comprises the following chemical components of, in percentage by weight, 0.35-0.40% of C, 6.00 -6.30% of Mn, 2.20-2.35% of Al, 0-0.027% of Nb, 0.030 -0.074% of Si, 0.05% of P,0.02% of S, and the balance Fe and inevitable impurities. The preparation method comprises the steps of raw material preparation, smelting, casting, forging, hot rolling and two-phase region annealing. According to the high-toughness hot-rolled medium manganese steel, strength of extension is 1039-1183 MPa, after-fracture elongation rate is 43.5-64.8%, strength-ductility balance can reach more than 60 GPa.%, but not greater than 72GPa.%. Through reasonable component proportion and optimized two-phase region annealing process, morphology and proportion of a two-phase structure are controlled, TRIP and TWIP effects are effectively simulated to reach a high work hardening rate, the strength and the toughness of the medium manganese steel are greatly improved, and performance indexes of different components of an automobile are met.

Description

technical field [0001] The invention belongs to the technical field of high-strength and toughness automobile steel, and in particular relates to a hot-rolled medium manganese steel with a strength-plasticity product greater than 60GPa·% and a preparation method thereof. Background technique [0002] With the deterioration of the environment and the increasing shortage of energy, energy conservation, safety and environmental protection have become the main directions of the development of the modern automobile industry, which has promoted the development of advanced high-strength steel for automobiles. According to statistics, the fuel consumption of a car has a linear relationship with its own weight. For every 10% reduction in the weight of a car, the fuel consumption can be reduced by 6-8%, and every 1L of fuel consumption can be reduced by 2.45kg of CO emissions. 2 . Therefore, using advanced high-strength steel with high strength and plasticity as the manufacturing mat...

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): C22C38/02C22C38/04C22C38/06C22C38/12C21D8/02C22C33/04
CPCC21D8/0205C21D8/0226C21D8/0263C22C33/04C22C38/02C22C38/04C22C38/06C22C38/12
Inventor 宋仁伯李佳佳李轩周乃鹏王永金
Owner UNIV OF SCI & TECH BEIJING
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