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CN-122012860-A - Smelting method of Mn13 wear-resistant steel

CN122012860ACN 122012860 ACN122012860 ACN 122012860ACN-122012860-A

Abstract

The invention discloses a smelting method of Mn13 wear-resistant steel, and belongs to the technical field of special steel smelting. The method comprises the steps of (1) dephosphorizing a ladle, (2) adding dephosphorized molten iron into an AOD converter for decarburization and reduction treatment, wherein manganese alloying is not carried out in the process, (3) tapping steel into a ladle and deslagging, (4) adding electrolytic manganese pre-melted in an intermediate frequency furnace into the ladle, (5) LF refining, and (6) continuous casting. According to the invention, the manganese alloying process is transferred from the AOD furnace to the subsequent process, and only decarburization is focused in the AOD furnace, so that the problem that decarburization is inhibited due to the fact that the content of manganese oxide in slag is increased due to the fact that a large amount of manganese alloy is added into the AOD furnace is avoided, thereby remarkably improving decarburization efficiency, shortening smelting period and reducing aluminum consumption caused by heating. And the intermediate frequency furnace is adopted to premelt electrolytic manganese, so that the yield of manganese is improved. And by utilizing equipment for smelting stainless steel, micro Cr can be brought in, so that the production cost is reduced.

Inventors

  • FU ZHISHENG
  • CHEN XINGRUN

Assignees

  • 甘肃酒钢集团宏兴钢铁股份有限公司

Dates

Publication Date
20260512
Application Date
20260305

Claims (9)

  1. 1. The smelting method of Mn13 wear-resistant steel is characterized by comprising the following steps of: (1) Dephosphorizing a ladle, namely dephosphorizing and preprocessing blast furnace molten iron in the ladle to obtain preprocessed molten iron; (2) An AOD converter treatment, namely adding the pretreated molten iron obtained in the step (1) into an AOD converter, and carrying out decarburization and reduction treatment to obtain AOD molten steel, wherein manganese alloying is not carried out in the AOD converter treatment process; (3) Tapping and slag skimming, namely tapping the AOD molten steel obtained in the step (2) to a ladle, and then carrying out slag skimming treatment on the ladle; (4) Adding manganese liquid, namely adding the electrolytic manganese liquid which is melted in the intermediate frequency furnace in advance into the molten steel after slag skimming in the step (3); (5) LF refining, namely carrying out LF refining treatment on the molten steel after the electrolytic manganese liquid is added in the step (4); (6) And (5) continuous casting, namely continuously casting the molten steel refined in the step (5) to obtain the Mn13 wear-resistant steel plate blank.
  2. 2. The smelting method of Mn13 wear-resistant steel according to claim 1, wherein in the step (1), the pretreated molten iron comprises, by mass, 3.0-3.7% of C, less than or equal to 0.10% of Si, 0.10-0.20% of Mn, less than or equal to 0.010% of P and 0.04-0.06% of S.
  3. 3. The method for smelting Mn13 wear-resistant steel according to claim 1, wherein in the step (2), argon is blown in the whole process of the AOD converter treatment process, the slag alkalinity in the reduction stage is controlled to be 2.2-2.6, and aluminum is used for reduction.
  4. 4. The method for smelting Mn13 wear-resistant steel according to claim 1 or 3, wherein in the step (2), the composition of the AOD molten steel comprises, by mass, 1.00-1.20% of C, 0.30-0.80% of Si, 0.10-0.20% of Mn, less than or equal to 0.010% of P, less than or equal to 0.002% of S, 0.01-0.05% of Al and 0.30-0.80% of Cr.
  5. 5. The method for smelting Mn13 wear-resistant steel according to claim 1, wherein in the step (3), the tapping temperature is 1600-1650 ℃, and the slag amount of the steel ladle after slag skimming is less than or equal to 50mm.
  6. 6. The method for smelting Mn13 wear-resistant steel according to claim 1, wherein in the step (4), the Mn content of electrolytic manganese is more than or equal to 99.9%, and the addition amount of electrolytic manganese liquid is 120-150 Kg/t molten steel.
  7. 7. The method for smelting Mn13 wear-resistant steel according to claim 1, wherein in the step (5), the LF refining comprises adding lime and fluorite to perform slag formation, heating for 10-20 minutes, adjusting the composition and temperature of molten steel, feeding calcium wires, and performing weak argon blowing treatment.
  8. 8. The method for smelting Mn13 wear-resistant steel according to claim 1, wherein in the step (6), the tundish temperature for continuous casting is 1425-1440 ℃, and the casting pulling rate is 0.6-0.7 m/min.
  9. 9. The smelting method of Mn13 wear-resistant steel according to claim 1, wherein the Mn13 wear-resistant steel slab obtained in the step (6) comprises, by mass, 1.00-1.20% of C, 0.30-0.80% of Si, 12.8-14.0% of Mn, less than or equal to 0.010% of P, less than or equal to 0.002% of S, 0.01-0.05% of Al and 0.30-0.80% of Cr.

Description

Smelting method of Mn13 wear-resistant steel Technical Field The invention belongs to the technical field of special steel smelting, and particularly relates to a smelting method of Mn13 wear-resistant steel. Background Mn13 steel is a typical high-manganese wear-resistant steel, and is widely applied to key wear-resistant parts in the fields of mines, building materials, engineering machinery and the like because of excellent work hardening capacity and wear resistance under high-impact and high-wear working conditions. At present, the smelting of Mn13 steel mainly comprises the following process routes: An Electric Arc Furnace (EAF) -LF refining-Continuous Casting (CC) process has the problems of long smelting period, difficult decarburization of an electric furnace, easy splashing in the decarburization process and the like, and has safety risks; the intermediate frequency furnace-LF-CC process has strict requirements on raw materials, and low-carbon materials are required to be adopted because the intermediate frequency furnace cannot effectively decarbonize, so that the production cost is high; And in the dephosphorization converter-AOD-LF-continuous casting process, manganese alloy is required to be added in the AOD process, but the addition of manganese can improve the content of manganese oxide (MnO) in slag, inhibit decarburization reaction, reduce decarburization efficiency and prolong smelting period. Therefore, the development of an efficient, economical and safe Mn13 wear-resistant steel smelting method has important practical significance. Disclosure of Invention The invention aims to overcome the defects of the prior art and provide a high-efficiency, low-cost and safe smelting method of Mn13 wear-resistant steel. In order to achieve the above purpose, the invention adopts the following technical scheme: a smelting method of Mn13 wear-resistant steel comprises the following steps: (1) Dephosphorizing a ladle, namely dephosphorizing blast furnace molten iron in the ladle to obtain pretreated molten iron; the pretreated molten iron comprises, by mass, 3.0-3.7% of C, less than or equal to 0.10% of Si, 0.10-0.20% of Mn, less than or equal to 0.010% of P and 0.04-0.06% of S. (2) An AOD converter treatment, namely adding the pretreated molten iron obtained in the step (1) into an AOD converter, and carrying out decarburization and reduction treatment to obtain AOD molten steel, wherein manganese alloying is carried out without adding a manganese-containing alloy material in the AOD converter treatment process; argon is blown in the whole AOD smelting process, aluminum is adopted for reduction in the reduction stage, and the slag alkalinity is controlled to be 2.2-2.6; The AOD molten steel comprises, by mass, 1.00-1.20% of C, 0.30-0.80% of Si, 0.10-0.20% of Mn, less than or equal to 0.010% of P, less than or equal to 0.002% of S, 0.01-0.05% of Al and 0.30-0.80% of Cr. (3) Tapping and slag skimming, namely tapping the AOD molten steel obtained in the step (2) to a ladle, and then carrying out slag skimming treatment on the ladle, wherein the tapping temperature is 1600-1650 ℃, and the slag amount of the ladle after slag skimming is less than or equal to 50mm. (4) Adding manganese liquid, namely adding the electrolytic manganese liquid which is melted in an intermediate frequency furnace in advance into the molten steel after slag skimming in the step (3), wherein the mass percentage of Mn in the electrolytic manganese is more than or equal to 99.9%, and the adding amount of the electrolytic manganese liquid is 120-150 Kg per ton of molten steel. (5) LF refining, namely LF refining treatment is carried out on molten steel obtained by adding electrolytic manganese in the step (4), wherein the LF refining process comprises the steps of adding lime and fluorite for slagging, heating for 10-20 minutes, adjusting the components and temperature of molten steel, feeding a calcium line, and carrying out weak argon blowing treatment. (6) And (5) continuous casting, namely continuously casting the molten steel refined in the step (5) to obtain the Mn13 wear-resistant steel plate blank. The temperature of the continuous casting tundish is 1425-1440 ℃, and the casting pulling speed is 0.6-0.7 m/min. The chemical components of the Mn13 wear-resistant steel slab are, by mass, 1.00-1.20% of C, 0.30-0.80% of Si, 12.8-14.0% of Mn, less than or equal to 0.010% of P, less than or equal to 0.002% of S, 0.01-0.05% of Al and 0.30-0.80% of Cr. Compared with the prior art, the invention has the following beneficial effects: 1. The invention only carries out decarburization and reduction in the AOD converter, and does not carry out manganese alloying. This avoids the severe influence of the addition of a large amount of cold electrolytic manganese on the temperature of the molten pool, ensures the high temperature environment required in the decarburization process, and reduces the consumption of aluminum for heating. More im