CN113416901A - High-magnetism-sensitivity weather-proof soft magnetic steel with excellent low-temperature toughness and production method thereof - Google Patents

High-magnetism-sensitivity weather-proof soft magnetic steel with excellent low-temperature toughness and production method thereof Download PDF

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CN113416901A
CN113416901A CN202110724889.8A CN202110724889A CN113416901A CN 113416901 A CN113416901 A CN 113416901A CN 202110724889 A CN202110724889 A CN 202110724889A CN 113416901 A CN113416901 A CN 113416901A
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CN113416901B (en
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童明伟
卜勇
梁宝珠
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Baowu Group Echeng Iron and Steel Co Ltd
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Baowu Group Echeng Iron and Steel Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/28—Manufacture of steel in the converter
    • C21C5/30—Regulating or controlling the blowing
    • C21C5/35—Blowing from above and through the bath
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/10—Handling in a vacuum
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/12—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
    • C21D8/1216—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties the working step(s) being of interest
    • C21D8/1222—Hot rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/12—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
    • C21D8/1244—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties the heat treatment(s) being of interest
    • C21D8/1261—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties the heat treatment(s) being of interest following hot rolling
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C33/00—Making ferrous alloys
    • C22C33/04—Making ferrous alloys by melting
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/001—Ferrous alloys, e.g. steel alloys containing N
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/008—Ferrous alloys, e.g. steel alloys containing tin
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/42—Ferrous alloys, e.g. steel alloys containing chromium with nickel with copper

Abstract

The invention discloses high-magnetism-sensitivity weather-proof soft magnetic steel with excellent low-temperature toughness and a production method thereof, and a soft magnetic steel ladleThe chemical components with the following mass fractions: c: 0.015 to 0.028%, Si: 2.12-2.85%, Mn: 0.05-0.25%, P is less than or equal to 0.0010%, S is less than 0.0010%, Cr: 0.25-0.58%, Cu: 0.61-0.75%, Ni: 0.78-1.05%, Al: 0.05-0.10%, As < 0.0010%, Sn < 0.0010%, [ N%]≤12×10‑4%，[O]≤10×10‑4Percent, the balance being Fe and unavoidable impurities, and the chemical components also have to satisfy the formula: (1) si +2.7Al = 2.35-3.05%, (2) (Cr + Cu)/Ni = 0.9-1.6; the production method comprises the following steps: molten iron desulfurization, converter blowing, external refining, vacuum treatment, pouring, casting blank heating, rolling, cooling and normalizing; the steel has low production cost and simple working procedure, and can be implemented in various metallurgical enterprises; the steel material has the characteristics of high toughness, excellent magnetic sensitivity, weather resistance and the like, and can be used for key functional components which realize the functions of supporting, guiding and traction by relying on electromagnetic force, such as a lateral guide plate of a magnetic suspension train and the like.

Description

High-magnetism-sensitivity weather-proof soft magnetic steel with excellent low-temperature toughness and production method thereof
Technical Field
The invention relates to the technical field of low alloy steel manufacturing, in particular to high-magnetism-sensitivity weather-resistant soft magnetic steel with excellent low-temperature toughness and a production method thereof.
Background
The soft magnetic steel is mainly used for key components of a lateral guide plate of a magnetic suspension train, an automobile generator, an electromagnetic valve, a magnetic pole section or claw level and the like which realize the functions by means of electromagnetic force. In order to realize the high performance of the appearance of components and parts of electrical equipment, the performance requirements of soft magnetic steel materials are higher and higher, and the soft magnetic steel is required to have high magnetic permeability, high magnetic flux density and low iron loss, and also has good low-temperature toughness and other properties, so that the existing common soft magnetic steel cannot meet the requirements of safe and reliable operation, energy conservation, environmental protection and the like of equipment such as a magnetic suspension train and the like.
Before the invention, the Patent US Patent4350525 elaborates the component range and the production process in detail, and puts forward requirements on magnetic induction performance and 0 ℃ impact toughness, but the magnetic induction performance and the impact toughness of the soft magnetic steel are not ideal, the magnetic induction performance B3 and B40 are only 0.60T and 1.58T, the longitudinal and transverse 0 ℃ impact toughness is 58J and 32J respectively, so that the electromagnetic conversion efficiency is not high, and increasingly strict performance and environmental protection requirements cannot be met.
Chinese patent No. 01126937.5 discloses a high performance soft magnetic steel for magnetic suspension train, which comprises the following chemical components by weight percent: 0.010-0.070%, Si: 1.0-2.0%, Mn: 0.30-0.80%, P is less than or equal to 0.02%, S is less than or equal to 0.010%, and AlT: 0.020-0.090%, Cr: 0.60-1.0%, Cu: 0.20-0.60 percent of Ti, less than or equal to 0.0080 percent of Ti, less than or equal to 0.01 percent of N, less than or equal to 0.80 percent of Ni, and less than or equal to 100ppm of Ca. The steel has high strength and toughness, high magnetic induction, high resistivity and excellent diamagnetism, but the P, S content is high, and the impact toughness at 0 ℃ is only required.
The Chinese patent with patent number 94105234.6 discloses a soft magnetic steel and a manufacturing method thereof, wherein the chemical components and the weight percentage are that C is less than or equal to 0.007%, Mn is less than or equal to 0.50%, P is less than or equal to 0.20%, S is less than or equal to 0.010%, N is less than or equal to 0.01%, O is less than or equal to 0.005%, Si +1.4 xAl is more than or equal to 0.5% and less than or equal to 3.5%, the grain size is required to be at least 0.2mm, and B25= 1.35-1.58T, but the invention does not require impact toughness and weather resistance.
The Chinese invention patent with patent number 97197182.X discloses a high-energy weldable soft magnetic steel and application thereof to magnetic suspension rail components, wherein the chemical components and weight percentage are that C is less than or equal to 0.15%, Si: more than 1.0-2.0%, Mn: 0.15 to less than 0.6 percent, P is less than or equal to 0.045 percent, Cu: 0.25-0.55%, Cr: 0.65 to < 1.0%, Als: 0.02 to 0.07%, Ti: 0.01-0.02%, N: 0.003-0.008% and Ti/N = 2.0-4.0. The invention can be welded in high energy, and has high resistivity, good aging resistance and atmospheric corrosion resistance. The Cu and Cr alloy of the invention has high content, increases the manufacturing cost, and has no requirement on impact toughness although the alloy has a requirement on strength index.
The invention patents in China with patent numbers of 201510925592.2 and 201510966905.9 respectively disclose a soft magnetic steel material and a soft magnetic steel part with excellent electromagnetic property and a manufacturing method thereof, and a soft magnetic steel material and a soft magnetic steel part with excellent forgeability and a manufacturing method thereof, wherein the two products both belong to the shapes of wires or bars, are produced by adopting a hot rolling or hot forging + 560-790 ℃ heat treatment process, and have good electromagnetic property or low iron loss, but the two invention patents have complex process routes and do not have requirements on strength, toughness and weather resistance.
Disclosure of Invention
The invention provides high-magnetic-sensitivity weather-resistant soft magnetic steel with excellent low-temperature toughness and a production method thereof, and aims to overcome the defects existing in the technical field at present. The method has the advantages of low cost, simple process, short period and the like, and can be implemented in various metallurgical enterprises. The steel produced by the method has the characteristics of high toughness, excellent magnetic sensitivity, weather resistance and the like, and can be used for key components of the functions of a side guide plate of a magnetic suspension train, an automobile generator, an electromagnetic valve, a magnetic pole section or a claw level and the like depending on electromagnetic force.
The invention relates to high-magnetism-sensitivity weather-resistant soft magnetic steel with excellent low-temperature toughness, which comprises the following chemical components in percentage by mass: c: 0.015 to 0.028%, Si: 2.12-2.85%, Mn: 0.05-0.25%, P is less than or equal to 0.0010%, S is less than 0.0010%, Cr: 0.25-0.58%, Cu: 0.61-0.75%, Ni: 0.78-1.05%, Al: 0.05-0.10%, As < 0.0010%, Sn < 0.0010%, [ N%]≤12×10-4%，[O] ≤10×10-4Percent, the balance being Fe and unavoidable impurities, and the chemical components also have to satisfy the formula: (1) si +2.7Al = 2.35-3.05%, (2) (Cr + Cu)/Ni = 0.9-1.6.
Preferably, the Si: 2.24-2.76%, Al: 0.056 to 0.092 percent.
Soft magnetic steel produced by the invention is KV at-30 DEG C2Longitudinal impact toughness of 214-3≥1.00T，B40≥1.65T，B50≥1.70T。
The invention relates to a production method of high-magnetic-sensitivity weather-resistant soft magnetic steel with excellent low-temperature toughness, which comprises the following steps: molten iron desulfurization, converter top and bottom combined blowing, external refining, vacuum treatment, full-process protective pouring, casting blank heating, rolling, cooling and normalizing heat treatment, wherein:
(1) and (3) top-bottom combined blowing of the converter: smelting by adopting a double-slag method, wherein the As of incoming molten iron is required to be less than 0.0010%, the Sn is required to be less than 0.0010%, and the P is required to be less than or equal to 0.010%, the P is controlled to be less than 0.0010% before tapping, and the point blowing is forbidden in the tapping process, so that the slag thickness is ensured to be less than or equal to 100mm, and the nitrogen increase is avoided;
(2) refining outside the furnace: refining time is more than or equal to 30min, and nitrogen increase is strictly prohibited during the refining time;
(3) and (3) vacuum treatment: the vacuum degree is less than or equal to 0.10kPa, the treatment time is more than or equal to 12min, and the soft argon blowing time is 3-5 min;
(4) and (3) protecting and pouring the whole process: the superheat degree is 10-15 ℃, the drawing speed is 0.76-0.78 m/min, and the thickness specification of a casting blank is 200-250 mm;
(5) heating a casting blank: heating at 1300-1320 ℃, soaking at 1260-1280 ℃, and soaking for more than or equal to 60 min;
(6) rolling and cooling: the initial rolling temperature of rough rolling is 1180-1200 ℃, the initial rolling temperature of finish rolling is 1030-1080 ℃, the final rolling temperature of finish rolling is 920-980 ℃, and then the steel plate is placed in air for natural cooling, and the cooling speed is controlled to be less than or equal to 2 ℃/s;
(7) normalizing heat treatment: normalizing at 970-980 ℃, keeping the temperature in the furnace for (h + 50-60) min, keeping the temperature at 1/3h + 15-20 min, and cooling the steel plate at a cooling speed of less than or equal to 1.2 ℃/s after the steel plate is taken out of the furnace, wherein h is the thickness value of the finished steel plate in mm.
Preferably, the start rolling temperature of the finish rolling is 1040-1070 ℃, and the finish rolling temperature of the finish rolling is 930-970 ℃.
The reasons for the limited amounts of the chemical components in the present invention are detailed below:
the content of C is selected to be 0.015-0.028%, and the strength is improved but the low-temperature toughness is damaged by the C through solid solution strengthening. C expands an austenite phase region, reduces the phase transition temperature, is not beneficial to grain growth and is extremely unfavorable for magnetic induction, but the content of C is too low, the content of O in steel can be increased, and the magnetic induction performance is also not beneficial, so the content of C is limited to 0.015-0.028%.
The Si content of the invention is selected to be 2.12-2.85%, and the Si has decisive influence on the structure and the magnetic induction performance. Si reduces austenite phase region, raises phase transition temperature, promotes crystal grain growth, reduces crystal interface and is beneficial to magnetic induction performance. However, since the Si content is too high and the product is embrittled due to rapid deterioration of low-temperature toughness and adversely affects the rolling process, the Si content is limited to 2.12 to 2.85%, preferably 2.24 to 2.76%.
The content of Mn in the invention is selected to be 0.05-0.25%, Mn expands austenite phase region, reduces phase transition temperature, has the function of refining crystal grains and is not beneficial to magnetic induction performance. Mn combines with S to form elongated MnS inclusions, which are also extremely detrimental to the induction properties and toughness. Therefore, in order to ensure the magnetic induction properties and low-temperature toughness of the steel, the Mn content is limited to 0.05 to 0.25%.
P is less than or equal to 0.0010 percent, S is less than 0.0010 percent, P, S is easy to segregate at grain boundaries to prevent the grain boundaries from moving and growing up, and S is also easy to form strip MnS inclusions to be not beneficial to the magnetic induction performance and the low-temperature toughness, so that P and S are harmful impurity elements and the content of P, S is reduced as far as possible.
The Cr content of the steel plate is selected to be 0.25-0.58%, the Cr has a strong solid solution strengthening effect, the weather resistance is improved, the strength of the steel plate can be ensured under the condition of not damaging the toughness and the magnetic induction performance by properly adding the Cr, but Cr-containing compounds and inclusions are easily formed when the Cr content is too high, the magnetic induction performance and the low-temperature toughness are reduced, and the Cr content is limited to be 0.25-0.58% when the Cr content is too low, so that the weather resistance is not favorable.
The Cu content is selected to be 0.61-0.75%, the Cu belongs to an element with strong solid solution strengthening, the strength and the weather resistance of the steel plate can be ensured under the condition of not damaging the toughness and the magnetic induction performance by properly adding, but the strength and the weather resistance of the steel plate can not be ensured when the content is too low, and the low-temperature toughness is damaged when the content is too high, so the Cu content is limited to be 0.61-0.75%.
The Ni content is selected to be 0.78-1.05%, Ni is a ferromagnetic material, the iron-nickel alloy has excellent magnetic induction performance, the Ni is added together with Cu and Cr, the low-temperature toughness of steel is obviously improved, the magnetic induction and the weather resistance can be further improved, but the Ni content is too high, iron oxide scales which are difficult to fall off are easily generated on the surface of a steel plate besides the increase of the production cost, and the Ni content is limited to be 0.78-1.05% in order to ensure the magnetic induction performance, the low-temperature toughness and the weather resistance of products.
The Al is selected to be 0.05-0.10%, Al and N in steel are combined to form AlN particles, grain growth is hindered, impact toughness is improved by refining grains, and magnetic induction performance is damaged. But a proper amount of Al can promote the growth of crystal grains and is beneficial to the magnetic induction performance, and excessive Al can form large Al2O3Oxide inclusions adversely affect the magnetic induction properties and the low-temperature toughness, so that the Al content is limited to 0.05 to 0.10%, preferably 0.056 to 0.092%.
As is less than 0.0010 percent and Sn is less than 0.0010 percent, As and Sn in the steel are easy to segregate in crystal boundaries, and the low-temperature impact toughness and the magnetic induction performance are extremely adversely affected due to the excessively high content, so that the content of As and Sn in the steel is reduced As far As possible.
[ N ] of the invention]≤12×10-4%，[O]≤10×10-4Both N and O in the steel adversely affect the magnetic induction performance and the low-temperature toughness, and excessive N and O in the steel form particles or inclusions with elements such as Al, thereby inhibiting the growth of crystal grains and further damaging the magnetic induction performance, so that the contents of N and O are reduced as much as possible.
Meanwhile, the chemical components also have to meet the following requirements: (1) si +2.7Al = 2.35-3.05%, (2) (Cr + Cu)/Ni = 0.9-1.6. When Si +2.7Al > 3.05%, a large amount of silicate and Al are formed in the steel2O3Oxide inclusion is not beneficial to low-temperature impact toughness and magnetic induction performance, the manufacturing cost is also increased, and when Si +2.7Al is less than 2.35, the magnetic induction performance is not beneficial; when (Cr + Cu)/Ni is less than 0.9, the strength and weather resistance of the steel sheet cannot be ensured, and when (Cr + Cu)/Ni is greater than 1.6, the low-temperature toughness is not good, so that the chemical composition must satisfy the requirements of Si +2.7Al =2.35 to 3.05% and (Cr + Cu)/Ni =0.9 to 1.6 in order to ensure that the product has excellent magnetic sensitivity, weather resistance, low-temperature toughness, and the like at the same time.
The steel of the present invention contains the above chemical components, and the balance of Fe and inevitable impurities.
The invention aims to provide high-magnetism-sensitivity weather-resistant soft magnetic steel with excellent low-temperature toughness and a production method thereof, and the related steel finished product has the advantages of excellent magnetic induction performance, low-temperature toughness, weather resistance and the like, can be implemented in various metallurgical enterprises, and ensures the performance of the finished product in accurate control of process parameters, and has the following specific measures:
the converter top-bottom composite blowing adopts a double-slag method for smelting, the incoming molten iron requires that As is less than 0.0010%, Sn is less than 0.0010% and P is less than or equal to 0.010% so As to reduce the content of As, Sn and P in the finished product As far As possible and ensure that P is less than 0.0010% before tapping; blowing is forbidden in the tapping process, and the slag thickness is ensured to be less than or equal to 100mm so as to avoid nitrogen increase. Controlling the external refining time to be more than or equal to 30min so as to desulfurize and deoxidize as far as possible, avoiding the magnetic induction performance and impact toughness from being damaged due to high S and O content, promoting the components and temperature of the molten steel to be uniform by argon blowing, strictly prohibiting nitrogen increase in the process, and ensuring that the P content of a finished product is less than or equal to 0.0010%. In order to promote the inclusions to float sufficiently and ensure that the steel has high purity, low-temperature toughness, magnetic sensitivity and other properties, the vacuum process parameters required by the invention are required to be controlled. In order to avoid the increase of the content of P in the molten steel and secondary oxidation caused by the contact of the molten steel and air, the whole-process protective pouring process is strictly executed, the superheat degree is controlled to be 10-15 ℃ so as to reduce the internal defects of central porosity, segregation and the like of a casting blank, and the casting blank crack caused by large structural stress can be avoided by adopting a constant pulling speed and controlling a small pulling speed fluctuation range so as to ensure that the steel plate has excellent performances such as magnetic induction performance, low-temperature toughness and the like.
The proper grain size can improve the magnetic induction performance of the steel, so the heating temperature, the soaking time, the rough rolling initial temperature, the finish rolling temperature and the cooling speed after rolling, the normalizing temperature, the normalizing time and the cooling speed of a casting blank are controlled within the specified range of the invention, and the phenomenon that the grain size is too large or too small due to improper temperature and time to damage the low-temperature toughness or the magnetic induction performance, so that the two performances can not be considered simultaneously is prevented.
It is worth to be noted that the steel plate manufactured by strictly adopting the chemical components, converter smelting, external refining, RH vacuum treatment, rolling, cooling and normalizing process parameters of the invention can meet the performance requirements of the steel of the invention through repeated experiments and verifications of the inventor.
Compared with the prior art, the invention has the following beneficial effects:
(1) the product of the invention has the characteristics of excellent magnetic induction performance, low-temperature toughness, weather resistance and the like, and can be used for key components of the functions of a side guide plate of a magnetic suspension train, an automobile generator, an electromagnetic valve, a magnetic pole section or a claw level and the like depending on electromagnetic force.
(2) Compared with the prior art, the method has the advantages of simple manufacturing process, short production period and the like, and can be implemented in various metallurgical enterprises.
Detailed Description
In order to better explain the technical solution of the present invention, the technical solution of the present invention is further described below with reference to specific examples, which are only exemplary to illustrate the technical solution of the present invention and do not limit the present invention in any way.
Table 1 below is a list of values of chemical components of each example and comparative example of the present invention;
table 2 below is a list of values of the main process parameters of the examples and comparative examples of the present invention;
table 3 below shows the mechanical property test results of the examples of the present invention and the comparative examples.
Wherein the product thicknesses of examples 1 to 8 were 10mm, 20mm, 30mm, 40mm and 50mm, respectively, and the product thickness of the comparative example was 30 mm.
The high-magnetism-sensitivity weather-resistant soft magnetic steel with excellent low-temperature toughness comprises the following chemical components in percentage by mass: c: 0.015 to 0.028%, Si: 2.12-2.85%, Mn: 0.05-0.25%, P is less than or equal to 0.0010%, S is less than 0.0010%, Cr: 0.25-0.58%, Cu: 0.61-0.75%, Ni: 0.78-1.05%, Al: 0.05-0.10%, As < 0.0010%, Sn < 0.0010%, [ N%]≤12×10-4%，[O] ≤10×10-4Percent, the balance being Fe and unavoidable impurities, and the chemical components also have to satisfy the formula: (1) si +2.7Al = 2.35-3.05%, (2) (Cr + Cu)/Ni = 0.9-1.6.
The production method of the high-magnetic-sensitivity weather-resistant soft magnetic steel with excellent low-temperature toughness comprises the following steps: molten iron desulfurization, converter top and bottom combined blowing, external refining, vacuum treatment, full-process protective pouring, casting blank heating, rolling, cooling and normalizing heat treatment, wherein:
(1) and (3) top-bottom combined blowing of the converter: smelting by adopting a double-slag method, wherein the As of incoming molten iron is required to be less than 0.0010%, the Sn is required to be less than 0.0010%, and the P is required to be less than or equal to 0.010%, the P is controlled to be less than 0.0010% before tapping, and the point blowing is forbidden in the tapping process, so that the slag thickness is ensured to be less than or equal to 100mm, and the nitrogen increase is avoided;
(2) refining outside the furnace: refining time is more than or equal to 30min, and nitrogen increase is strictly prohibited during the refining time;
(3) and (3) vacuum treatment: the vacuum degree is less than or equal to 0.10kPa, the treatment time is more than or equal to 12min, and the soft argon blowing time is 3-5 min;
(4) and (3) protecting and pouring the whole process: the superheat degree is 10-15 ℃, the drawing speed is 0.76-0.78 m/min, and the thickness specification of a casting blank is 200-250 mm;
(5) heating a casting blank: heating at 1300-1320 ℃, soaking at 1260-1280 ℃, and soaking for more than or equal to 60 min;
(6) rolling and cooling: the initial rolling temperature of rough rolling is 1180-1200 ℃, the initial rolling temperature of finish rolling is 1030-1080 ℃, the final rolling temperature of finish rolling is 920-980 ℃, and then the steel plate is placed in air for natural cooling, and the cooling speed is controlled to be less than or equal to 2 ℃/s;
(7) normalizing heat treatment: normalizing at 970-980 ℃, keeping the temperature in the furnace for (h + 50-60) min, keeping the temperature at 1/3h + 15-20 min, and cooling the steel plate at a cooling speed of less than or equal to 1.2 ℃/s after the steel plate is taken out of the furnace, wherein h is the thickness value of the finished steel plate in mm.
TABLE 1 tabulated (wt,%) list of chemical compositions for each example of the invention and comparative example
Figure DEST_PATH_IMAGE002
TABLE 2 tabulation of values of the main process parameters for each example of the invention and comparative example
Figure DEST_PATH_IMAGE004
TABLE 3 mechanical Property test results of inventive and comparative examples
Figure DEST_PATH_IMAGE006
The steel plates of the examples and the comparative examples of the invention were sampled and tested for room temperature tensile properties, longitudinal impact toughness at-30 ℃, corrosion rate after 264h immersion, and magnetic induction properties. The test result shows that the product produced by the components and the process has good obdurability matching and weather resistance, the magnetic induction characteristics of the product under the magnetic field strengths of 300A/m, 4000A/m and 5000A/m are respectively more than 1.00T, 1.65T and 1.70T, the product has excellent magnetic induction characteristics, and the comprehensive performance index is obviously superior to that of a comparative example.
The embodiments described above are merely specific examples of the present invention exemplified for explaining the present invention, and do not limit the present invention in any way, and any insubstantial changes from the above-described contents and forms without departing from the scope of the present invention are considered to fall within the scope of the present invention as claimed. The invention is not limited to the specific embodiments described above.

Claims (5)

1. The high-magnetic-sensitivity weather-resistant soft magnetic steel with excellent low-temperature toughness is characterized by comprising the following chemical components in percentage by mass: c: 0.015 to 0.028%, Si: 2.12-2.85%, Mn: 0.05-0.25%, P is less than or equal to 0.0010%, S is less than 0.0010%, Cr: 0.25-0.58%, Cu: 0.61-0.75%, Ni: 0.78-1.05%, Al: 0.05-0.10%, As < 0.0010%, Sn < 0.0010%, [ N%]≤12×10-4%，[O] ≤10×10-4Percent, the balance being Fe and unavoidable impurities, and the chemical components also have to satisfy the formula: (1) si +2.7Al = 2.35-3.05%, (2) (Cr + Cu)/Ni = 0.9-1.6.
2. The high-magnetic-sensitivity weather-resistant soft magnetic steel with excellent low-temperature toughness according to claim 1, wherein: the Si: 2.24-2.76%, Al: 0.056 to 0.092 percent.
3. The high-magnetic-sensitivity weather-resistant soft magnetic steel with excellent low-temperature toughness according to claim 1, wherein: the soft magnetic steel is KV at-30 DEG C2Longitudinal impact toughness of 214-3≥1.00T，B40≥1.65T，B50≥1.70T。
4. A method for producing a high-magnetic-sensitivity weather-resistant soft magnetic steel excellent in low-temperature toughness according to claim 1, 2 or 3, comprising: molten iron desulfurization, converter top and bottom combined blowing, external refining, vacuum treatment, full-flow protective pouring, casting blank heating, rolling, cooling and normalizing heat treatment, and is characterized in that:
(1) and (3) top-bottom combined blowing of the converter: smelting by adopting a double-slag method, wherein the As of incoming molten iron is required to be less than 0.0010%, the Sn is required to be less than 0.0010%, and the P is required to be less than or equal to 0.010%, the P is controlled to be less than 0.0010% before tapping, and the point blowing is forbidden in the tapping process, so that the slag thickness is ensured to be less than or equal to 100mm, and the nitrogen increase is avoided;
(2) refining outside the furnace: refining time is more than or equal to 30min, and nitrogen increase is strictly prohibited during the refining time;
(3) and (3) vacuum treatment: the vacuum degree is less than or equal to 0.10kPa, the treatment time is more than or equal to 12min, and the soft argon blowing time is 3-5 min;
(4) and (3) protecting and pouring the whole process: the superheat degree is 10-15 ℃, the drawing speed is 0.76-0.78 m/min, and the thickness specification of a casting blank is 200-250 mm;
(5) heating a casting blank: heating at 1300-1320 ℃, soaking at 1260-1280 ℃, and soaking for more than or equal to 60 min;
(6) rolling and cooling: the initial rolling temperature of rough rolling is 1180-1200 ℃, the initial rolling temperature of finish rolling is 1030-1080 ℃, the final rolling temperature of finish rolling is 920-980 ℃, and then the steel plate is placed in air for natural cooling, and the cooling speed is controlled to be less than or equal to 2 ℃/s;
(7) normalizing heat treatment: normalizing at 970-980 ℃, keeping the temperature in the furnace for (h + 50-60) min, keeping the temperature at 1/3h + 15-20 min, and cooling the steel plate at a cooling speed of less than or equal to 1.2 ℃/s after the steel plate is taken out of the furnace, wherein h is the thickness value of the finished steel plate in mm.
5. The method for producing the high-magnetic-sensitivity weather-resistant soft magnetic steel with excellent low-temperature toughness according to claim 4, wherein the method comprises the following steps: the start rolling temperature of the finish rolling is 1040-1070 ℃, and the finish rolling temperature of the finish rolling is 930-970 ℃.
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1534105A (en) * 2003-03-31 2004-10-06 上海磁悬浮交通发展有限公司 Soft magnetic structure steel possessing good low temperature toughness and easy welding preformance and its manufacturing method
JP2005220394A (en) * 2004-02-04 2005-08-18 Sumitomo Metal Ind Ltd Seawater corrosion resisting steel
CN1863934A (en) * 2003-10-06 2006-11-15 新日本制铁株式会社 High-strength magnetic steel sheet and worked part therefrom, and process for producing them
CN104884644A (en) * 2012-12-28 2015-09-02 杰富意钢铁株式会社 Process for producing grain-oriented electromagnetic steel sheet
CN104968822A (en) * 2013-02-26 2015-10-07 新日铁住金株式会社 High-strength hot-rolled steel sheet having maximum tensile strength of 980 MPa or above, and having excellent and baking hardenability and low-temperature toughness
CN106702260A (en) * 2016-12-02 2017-05-24 武汉钢铁股份有限公司 High-magnetic-inductivity low-iron-loss non-oriented silicon steel and production method thereof
CN111926236A (en) * 2020-08-12 2020-11-13 宝武集团鄂城钢铁有限公司 Method for producing steel plate with excellent Z-direction performance for welding structure by adopting continuous casting billet under condition of small compression ratio

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1534105A (en) * 2003-03-31 2004-10-06 上海磁悬浮交通发展有限公司 Soft magnetic structure steel possessing good low temperature toughness and easy welding preformance and its manufacturing method
CN1863934A (en) * 2003-10-06 2006-11-15 新日本制铁株式会社 High-strength magnetic steel sheet and worked part therefrom, and process for producing them
JP2005220394A (en) * 2004-02-04 2005-08-18 Sumitomo Metal Ind Ltd Seawater corrosion resisting steel
CN104884644A (en) * 2012-12-28 2015-09-02 杰富意钢铁株式会社 Process for producing grain-oriented electromagnetic steel sheet
CN104968822A (en) * 2013-02-26 2015-10-07 新日铁住金株式会社 High-strength hot-rolled steel sheet having maximum tensile strength of 980 MPa or above, and having excellent and baking hardenability and low-temperature toughness
CN106702260A (en) * 2016-12-02 2017-05-24 武汉钢铁股份有限公司 High-magnetic-inductivity low-iron-loss non-oriented silicon steel and production method thereof
CN111926236A (en) * 2020-08-12 2020-11-13 宝武集团鄂城钢铁有限公司 Method for producing steel plate with excellent Z-direction performance for welding structure by adopting continuous casting billet under condition of small compression ratio

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