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CN-122013067-A - High-strength corrosion-resistant steel and preparation method thereof

CN122013067ACN 122013067 ACN122013067 ACN 122013067ACN-122013067-A

Abstract

The invention relates to the technical field of steelmaking and provides high-strength corrosion-resistant steel and a preparation method thereof. The high-strength corrosion-resistant steel comprises a matrix and a reinforcing phase, wherein the matrix comprises the following components in percentage by mass: 0.04% -0.08% of C, 0.21% -0.55% of Si, 1.0% -1.5% of Mn, 0.5% -1.0% of Cr, 0.015% -0.025% of N, less than or equal to 0.02% of P, less than or equal to 0.008% of S, 0.1% -0.3% of Ni, 0.2% -0.5% of Cu, 0.045% -0.0875% of Ti, 0.015% -0.03% of Nb, and the balance of Fe and other unavoidable impurities, wherein Ti/N=3-3.5, nb/N=1-1.2. Through the technical scheme, the problems of toughness reduction and insufficient corrosion resistance of the nitrogen-containing steel in the prior art under a low-temperature environment are solved.

Inventors

  • SONG XIN
  • DONG JIANSHENG
  • ZHANG WEIJUN
  • DI LIN
  • FENG GUANGHONG
  • JI WEI
  • LIAN XINTONG
  • FANG YONGWEI
  • Xie yinke
  • WANG HUIBIN

Assignees

  • 秦皇岛佰工钢铁有限公司

Dates

Publication Date
20260512
Application Date
20260331

Claims (10)

  1. 1. The high-strength corrosion-resistant steel is characterized by comprising a matrix and a reinforcing phase, wherein the matrix comprises ：C 0.04%~0.08%、Si 0.21%~0.55%、Mn 1.0%~1.5%、Cr 0.5%~1.0%、N 0.015%~0.025%、P ≤0.02%、S ≤0.008%、Ni 0.1%~0.3%、Cu 0.2%~0.5%、Ti 0.045%~0.0875%、Nb 0.015%~0.03%、 parts by mass of Fe and other unavoidable impurities, the balance is Ti/N=3-3.5, and Nb/N=1-1.2.
  2. 2. A high strength corrosion resistant steel according to claim 1 wherein said reinforcing phase comprises alumina and silicon carbide coated ceria.
  3. 3. The high strength corrosion resistant steel of claim 2 wherein said method of preparing alumina and silicon carbide coated ceria comprises the steps of: Mixing aluminum oxide, silicon carbide and cerium oxide, adding ethanol, ball milling, drying, calcining and grinding to obtain aluminum oxide and silicon carbide coated cerium oxide.
  4. 4. A high strength corrosion resistant steel according to claim 3, wherein the mass ratio of cerium oxide, silicon carbide and aluminum oxide is 90:6-8:4-6; The volume ratio of the total mass of the cerium oxide, the silicon carbide and the aluminum oxide to the ethanol is 10 g:30-40 mL; The calcination temperature is 850-950 ℃.
  5. 5. A method for preparing the high-strength corrosion-resistant steel, which is used for preparing the high-strength corrosion-resistant steel according to any one of claims 1 to 4, and is characterized by comprising the following steps: Adding reinforcing phase into the molten steel, mixing, and continuously casting to obtain steel billet; and heating the steel billet, rough rolling, finish rolling, cooling and coiling to obtain the high-strength corrosion-resistant steel.
  6. 6. The method for producing high-strength corrosion-resistant steel according to claim 5, wherein the drawing speed of continuous casting is 2 to 2.5m/min.
  7. 7. The method for preparing high-strength corrosion-resistant steel according to claim 5, wherein the heating temperature is 1200-1300 ℃ and the heat preservation time is 60-80 min.
  8. 8. The method for producing high-strength corrosion-resistant steel according to claim 5, wherein the descaling treatment is performed before rough rolling, the initial rolling temperature of the rough rolling is 1100-1200 ℃, and the final rolling temperature is 1030-1130 ℃.
  9. 9. The method for producing a high-strength corrosion-resistant steel according to claim 5, wherein the descaling treatment is performed before the finish rolling, the start rolling temperature of the finish rolling is 930 to 1030 ℃, and the finish rolling temperature is 830 to 900 ℃.
  10. 10. The method for producing high-strength corrosion-resistant steel according to claim 5, wherein the water temperature of laminar flow water is 25-30 ℃ and the cooling speed is 20-30 ℃ per second during cooling; The coiling temperature is 530-600 ℃.

Description

High-strength corrosion-resistant steel and preparation method thereof Technical Field The invention relates to the technical field of steelmaking, in particular to high-strength corrosion-resistant steel and a preparation method thereof. Background The steel material is widely applied to various fields by virtue of excellent mechanical properties, and has strict requirements on the strength, toughness and corrosion resistance of steel along with the more and more severe conditions of part of application scenes. At present, the precipitation of large-particle carbide is inhibited by adding nitrogen element into steel so as to improve the corrosion resistance and fatigue resistance of the steel, but the existence form of nitrogen is difficult to precisely control in the smelting process, and free nitrogen is easy to generate. The residual free nitrogen in the steel is easy to be separated out in a low-temperature environment, the low-temperature aging embrittlement phenomenon is caused, the toughness of the steel is reduced, the steel is easy to break, and the service safety of parts is seriously affected. Disclosure of Invention The invention provides high-strength corrosion-resistant steel and a preparation method thereof, which solve the problems of toughness reduction and insufficient corrosion resistance of nitrogen-containing steel in the related art under a low-temperature environment. The technical scheme of the invention is as follows: The invention provides high-strength corrosion-resistant steel, which comprises a matrix and a reinforcing phase, wherein the matrix comprises ：C 0.04%~0.08%、Si 0.21%~0.55%、Mn 1.0%~1.5%、Cr 0.5%~1.0%、N 0.015%~0.025%、P ≤0.02%、S ≤0.008%、Ni 0.1%~0.3%、Cu 0.2%~0.5%、Ti 0.045%~0.0875%、Nb 0.015%~0.03%、 parts by mass of Fe and other unavoidable impurities, the balance is Ti/N=3-3.5, and Nb/N=1-1.2. As a further technical solution, the reinforcing phase includes alumina and silicon carbide coated cerium oxide. As a further technical scheme, the preparation method of the alumina and silicon carbide coated cerium oxide comprises the following steps: Mixing aluminum oxide, silicon carbide and cerium oxide, adding ethanol, ball milling, drying, calcining and grinding to obtain aluminum oxide and silicon carbide coated cerium oxide. As a further technical scheme, the mass ratio of the cerium oxide to the silicon carbide to the aluminum oxide is 90:6-8:4-6. The invention further improves the tensile strength of steel by taking alumina and silicon carbide coated cerium oxide as reinforcing phases, is uniformly distributed in a steel matrix, and has the advantages that dislocation sliding is performed by bypassing or cutting through the material, so that the dislocation movement resistance is improved, and the tensile strength is obviously improved. The mass ratio of cerium oxide, silicon carbide and aluminum oxide may be 90:6:4, 90:7:5, 90:8:6, preferably the mass ratio of cerium oxide, silicon carbide and aluminum oxide may be 90:7:5. As a further technical scheme, the volume ratio of the total mass of cerium oxide, silicon carbide and aluminum oxide to ethanol is 10 g:30-40 mL. As a further technical scheme, the rotation speed of the ball milling is 200-400 rpm, and the time is 1.5-2 h. As a further technical scheme, the drying temperature is 80-100 ℃ and the drying time is 12-15 h. As a further technical scheme, the calcining temperature is 850-950 ℃. The invention also provides a preparation method of the high-strength corrosion-resistant steel, which is used for preparing the high-strength corrosion-resistant steel and comprises the following steps of: Adding reinforcing phase into the molten steel, mixing, and continuously casting to obtain steel billet; and heating the steel billet, rough rolling, finish rolling, cooling and coiling to obtain the high-strength corrosion-resistant steel. As a further technical scheme, the continuous casting speed is 2-2.5 m/min. As a further technical scheme, the heating temperature is 1200-1300 ℃, and the heat preservation time is 60-80 min. As a further technical scheme, the descaling treatment is carried out before rough rolling, the initial rolling temperature of the rough rolling is 1100-1200 ℃, and the final rolling temperature is 1030-1130 ℃. As a further technical scheme, the descaling treatment is carried out before the finish rolling, the initial rolling temperature of the finish rolling is 930-1030 ℃, and the final rolling temperature is 830-900 ℃. As a further technical scheme, when cooling, the water temperature of laminar flow water is 25-30 ℃, and the cooling speed is 20-30 ℃ per second. As a further technical scheme, the coiling temperature is 530-600 ℃. The working principle and the beneficial effects of the invention are as follows: According to the invention, the proportion of Ti/N=3-3.5 and Nb/N=1-1.2 in the matrix is regulated, nitrogen is combined with Ti and Nb to form TiN and (Ti, nb) N compounds, the grain boundary can be