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CN-121972669-A - Preparation method of foam steel powder, foam steel and preparation method of foam steel

CN121972669ACN 121972669 ACN121972669 ACN 121972669ACN-121972669-A

Abstract

The invention relates to the technical field of foam steel production, in particular to a foam steel powder preparation method, foam steel and a foam steel preparation method, wherein the foam steel adopts the foam steel powder as a raw material, the chemical components of the foam steel are, by weight, 0.006% -0.010% of C, 0.01% -0.02% of Si, 0.02% -0.04% of Mn, less than or equal to 0.008% of P, less than or equal to 0.005% of S, the balance of Fe and impurities, the foam steel has the density of 2.1-2.4 g/cm 3 , the compressive yield strength of the foam steel is more than or equal to 110MPa, and the energy absorption value under 50% strain is 65-85 MJ/m 3 . Firstly, preparing hollow metal iron powder, namely foam steel powder, and then preparing foam steel by briquetting and sintering, wherein the sintered foam steel is made of a single material and has no residue, and the powder granularity and internal pores are uniformly distributed, so that the uniformity of the performance of the foam steel is ensured.

Inventors

  • LI GUANGBANG
  • JIA JIXIANG
  • WANG HAIWEI
  • Wei Chongyi
  • SUN SHEN
  • YANG GUANG

Assignees

  • 鞍钢股份有限公司

Dates

Publication Date
20260505
Application Date
20260211

Claims (7)

  1. 1. The preparation method of the foam steel powder is characterized by comprising the following steps: 1) The method comprises the steps of adopting industrial pure iron as a raw material, smelting the raw material in a pressurizing smelting furnace in an induction heating mode, specifically, vacuumizing the pressurizing smelting furnace, transmitting power for smelting after the vacuum degree is below 10Pa, controlling the smelting power to be 130-170 kW, charging nitrogen into the pressurizing smelting furnace for pressurizing, controlling the pressure in the pressurizing smelting furnace to be 4-5 MPa, and maintaining the pressure for 25-35 min, wherein the mass content of nitrogen in molten steel is 0.060% -0.070%; 2) The method comprises the steps of carrying out gas atomization and pulverization, namely adding carburant, ferrosilicon and manganese metal to carry out alloying after the industrial pure iron raw material is melted, controlling the superheat degree of molten steel to be 150-200 ℃, and preparing hollow metal iron powder by gas atomization after smelting is completed, wherein the gas pressure of gas sprayed by a gas atomization nozzle is 3.0-3.3 MPa, molten steel in a pressurized smelting furnace flows out into an atomization chamber through a flow guide pipe, and is crushed into small particles under the action of gas flow impact formed by gas sprayed by the gas atomization nozzle; 3) And collecting powder, namely collecting the iron powder in the powder collector after gas atomization, and screening to obtain the hollow metal iron powder with the granularity of 50-300 mu m, namely foam steel powder, wherein the loose packing density of the foam steel powder is 1.8-2.0 g/cm 3 .
  2. 2. The method for preparing foam steel powder according to claim 1, wherein in the step 1), the chemical components of the industrial pure iron are, by weight, less than or equal to 0.003% of C, less than or equal to 0.010% of Si, less than or equal to 0.02% of Mn, less than or equal to 0.006% of P, less than or equal to 0.003% of S, and the balance of iron and unavoidable impurities.
  3. 3. The method for preparing foam steel powder according to claim 1, wherein in the step 1), the purity of nitrogen is not less than 99.9%.
  4. 4. A method for preparing foam steel powder according to claim 1, wherein in the step 2), the diameter of the draft tube is bransted 4-8 mm, a pressure reducing valve is arranged in the atomizing chamber, and the set value of the pressure reducing valve is 1-1.1 atm.
  5. 5. A foam steel is characterized by adopting the foam steel powder prepared by the preparation method of the foam steel powder as a raw material, wherein the foam steel comprises, by weight, 0.006% -0.010% of C, 0.01% -0.02% of Si, 0.02% -0.04% of Mn, less than or equal to 0.008% of P, less than or equal to 0.005% of S, and the balance of Fe and unavoidable impurities, the foam steel has a density of 2.1-2.4 g/cm 3 , a compressive yield strength of more than or equal to 110MPa, and an energy absorption value of 65-85 MJ/m 3 under 50% strain.
  6. 6. The method for preparing foam steel according to claim 5, comprising the following steps: 1) The method comprises the steps of (1) pressing and forming, namely placing foam steel powder into a pressing die for vibration compaction to obtain foam steel powder briquettes, wherein the pressure during pressing is 30-45 MPa, and the pressing time is 9-15 min; 2) The vacuum sintering is carried out by placing the pressed foam steel powder briquette and the pressing die into a vacuum sintering furnace for presintering, heating at 60-90 ℃ per minute, keeping the temperature for 1.2-1.8 h after heating to 610-635 ℃, then continuously heating to 1060-1140 ℃, keeping the temperature for 2.1-2.4 h, vacuum degree is less than or equal to 2Pa in sintering process, cooling to room temperature with the vacuum sintering furnace after sintering, demoulding to obtain the foam steel with single material.
  7. 7. The method for preparing foam steel according to claim 6, wherein the pressing mold is an alloy steel mold, and the inner surface of the pressing mold is coated with a release agent.

Description

Preparation method of foam steel powder, foam steel and preparation method of foam steel Technical Field The invention relates to the technical field of foam steel production, in particular to a preparation method of foam steel powder, foam steel and a preparation method of foam steel. Background Foam steel is a structure-function integrated material in which a large number of communicated or non-communicated holes are uniformly distributed in a steel matrix. As a functional material, it has various properties of sound absorption, heat insulation, flame retardance, electromagnetic shielding and the like. As a structural material, the density, elastic modulus, and yield strength of the steel material can be changed by changing the porosity and pore structure. Under the condition of the same steel consumption, the overall stability and the local stability of the structural member can be effectively improved through reasonable design, so that the bearing capacity is improved, and the purpose of saving steel is achieved. Under the action of strong earthquake or impact load, the plastic compression of the pores can absorb a large amount of energy to avoid brittle failure of the structure, so that the foam steel has wide application prospect in the aspects of light steel structures, energy dissipation and shock absorption structures, earthquake resistant structures, impact resistance, explosion prevention structures and the like. At present, the preparation method of the foam steel mainly comprises a melt metal foaming method, a metal deposition method, a hollow sphere sintering method, a seepage method, a powder sintering method and the like. Wherein, the foaming agent is difficult to be uniformly dispersed into the melt by a melt metal foaming method, the size and the distribution uniformity of bubbles are difficult to be controlled, and the mechanical property of the obtained material is poor. The hollow sphere sintering method has the defects of difficult preparation of the hollow sphere, high requirements on process equipment and the like. The percolation method has the problems of long process flow, difficult complete removal of the precursor and the like. In contrast, the powder sintering method is a preparation method with simple process and low cost, and the porosity, pore size and pore size distribution can be effectively controlled. The Chinese patent application with the application number 201610257103.5 discloses a method for preparing foam steel by using a pore-forming agent, which takes pure iron powder and the pore-forming agent as raw materials, presses the raw materials after mixing, and sinters the raw materials under the protection of hydrogen to prepare the open-cell foam steel. However, as the pore-forming agent adopts dextrin powder and various starch powder, the main component is carbon element, and carbon can permeate into iron in the sintering process, so that the carbon content in the foam steel is unevenly distributed, and the performance of the foam steel is affected. The Chinese patent application with the application number 201110382548.3 discloses a preparation method of open-cell foam steel, which adopts sodium metaaluminate particles with different diameters, the melting point of which is higher than that of steel, as a precursor, steel is used as seepage fluid, the seepage fluid is infiltrated into the precursor by a pressure seepage method, a composite body is obtained after cooling, the precursor sodium metaaluminate is dissolved from the composite body by water, the size diameter of the precursor sodium metaaluminate particles is 0.1-10 mm, the sodium metaaluminate particles are dried at 1000-1100 ℃ for 5-6 hours, the sodium metaaluminate is preheated at 400-600 ℃ for 2-30 minutes before seepage, the melting temperature of a steel substrate is higher than that of the steel substrate, the seepage pressure is controlled to be 10-100 MPa during pressure seepage, the seepage temperature is 10-50 ℃ lower than that of the sodium metaaluminate particles, the seepage speed is 1-20 mm/s, and the composite body obtained after seepage is washed by water. According to the method, sodium metaaluminate particles are used as a seepage precursor, and the composite body after seepage is washed to remove sodium metaaluminate, but sodium metaaluminate cannot be thoroughly removed in the actual production process, and the sodium metaaluminate remained in metal can have adverse effects on the performance of the metal, so that the use effect of foam metal is seriously affected. In a word, the existing pore-forming agent and other precursors cannot be completely removed when the foam steel is prepared, so that adverse effects are generated on the performance of the foam steel, the performance of the foam steel is uneven, and the advantages of the foam steel cannot be exerted. Therefore, there is an urgent need to develop a preparation method of foam steel, which can not leave residues in the sinter