CN114836684A - Low-chromium soft magnetic stainless steel and preparation method and application thereof - Google Patents
Low-chromium soft magnetic stainless steel and preparation method and application thereof Download PDFInfo
- Publication number
- CN114836684A CN114836684A CN202210339735.1A CN202210339735A CN114836684A CN 114836684 A CN114836684 A CN 114836684A CN 202210339735 A CN202210339735 A CN 202210339735A CN 114836684 A CN114836684 A CN 114836684A
- Authority
- CN
- China
- Prior art keywords
- percent
- equal
- less
- stainless steel
- soft magnetic
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- 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
- 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
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/26—Methods of annealing
-
- 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
- C21D8/1216—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
- C21D8/1233—Cold 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
-
- 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
- C22C33/06—Making ferrous alloys by melting using master alloys
-
- 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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/50—Ferrous alloys, e.g. steel alloys containing chromium with nickel with titanium or zirconium
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
- H01F1/14—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys
- H01F1/147—Alloys characterised by their composition
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Materials Engineering (AREA)
- Electromagnetism (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Dispersion Chemistry (AREA)
- Power Engineering (AREA)
- Soft Magnetic Materials (AREA)
Abstract
The invention belongs to the technical field of new stainless steel materials in the ferrous metallurgy industry, and particularly relates to low-chromium soft magnetic stainless steel and a preparation method and application thereof. The invention provides low-chromium soft magnetic stainless steel, which comprises the following components in percentage by weight: c is less than or equal to 0.015 percent; 0.4 to 1.0 percent of Si; 0.15 to 0.30 percent of Mn; p is less than or equal to 0.030 percent; s is less than or equal to 0.005 percent; 11.0 to 13.5 percent of Cr; ni is less than or equal to 0.20 percent; 0.12 to 0.30 percent of Ti; n is less than or equal to 0.020%; the balance being Fe and unavoidable impurities. The low-chromium soft magnetic stainless steel has low raw material cost, and also has good corrosion resistance and electromagnetic performance.
Description
Technical Field
The invention belongs to the technical field of new stainless steel materials in the ferrous metallurgy industry, and particularly relates to low-chromium soft magnetic stainless steel and a preparation method and application thereof.
Background
The soft magnetic material is a material with low coercive force and high magnetic conductivity, and can be widely applied to electromagnetic valve bodies of electronic products in the household saloon car industry, the radio industry and the like. Common metal-based soft magnetic materials are pure iron and silicon steel. However, with the rapid development of automatic control technology and intelligent technology, after the two materials are processed into components, in order to ensure the corrosion resistance, electroplating or rust-proof coating must be applied, which results in increasing the production cost and bringing about the problem of environmental pollution. Therefore, it is very important to research and develop soft magnetic stainless steel with good corrosion resistance and electromagnetic performance.
The Chinese patent with publication number CN111471918A discloses a soft magnetic stainless steel, which comprises the following chemical components in percentage by weight: c is less than or equal to 0.015 percent; si: 1.9 to 2.1 percent; mn: 0.20-0.30%; p is less than or equal to 0.025 percent; s: 0.015-0.030%; cr: 14.5 to 15.5 percent; ni is less than or equal to 0.20 percent; mo: 0.40 to 0.45 percent; n is less than or equal to 0.020%; the balance being Fe and unavoidable impurities. It achieves its object in terms of corrosion resistance by increasing the Cr content, which undoubtedly increases the cost of the soft magnetic stainless steel product. From the aspect of improving magnetism, the product performance is improved by utilizing the Si element as an alloy component, and the smelting difficulty and the cost are increased.
Disclosure of Invention
The invention aims to provide low-chromium soft magnetic stainless steel and a preparation method and application thereof aiming at the defects of the prior art.
Specifically, in a first aspect, the present invention provides a low-chromium soft magnetic stainless steel, which comprises, by weight: c is less than or equal to 0.015 percent; 0.4 to 1.0 percent of Si; 0.15 to 0.30 percent of Mn; p is less than or equal to 0.030 percent; s is less than or equal to 0.005 percent; 11.0 to 13.5 percent of Cr; ni is less than or equal to 0.20 percent; 0.12 to 0.30 percent of Ti; n is less than or equal to 0.020%; the balance being Fe and unavoidable impurities.
Preferably, the low-chromium soft magnetic stainless steel comprises the following components in percentage by weight: c is less than or equal to 0.010 percent; 0.40 to 0.60 percent of Si; 0.15 to 0.25 percent of Mn; p is less than or equal to 0.025 percent; s is less than or equal to 0.001 percent; 11.0 to 12.50 percent of Cr; ni is less than or equal to 0.20 percent; 0.15 to 0.25 percent of Ti; n is less than or equal to 0.010 percent; the balance being Fe and unavoidable impurities.
In a second aspect, the present invention provides a method for preparing a low chromium soft magnetic stainless steel, comprising:
(1) smelting molten iron by adopting a converter, and introducing inert gas in the whole smelting process to obtain first molten steel;
(2) introducing the first molten steel into a VOD furnace, and performing vacuum decarburization and denitrification treatment to obtain second molten steel;
(3) introducing the second molten steel into an LF furnace, and adding ferrotitanium to adjust the titanium content to obtain third molten steel;
(4) and sequentially carrying out continuous casting, coping, hot rolling, annealing and pickling, cold rolling and bright annealing on the third molten steel to finally obtain the low-chromium soft magnetic stainless steel.
According to the preparation method of the low-chromium soft magnetic stainless steel, the first molten steel comprises the following components in percentage by weight: 0.20 to 0.30 percent of C, 0.05 to 0.15 percent of Si, 0.20 to 0.30 percent of Mn, less than or equal to 0.025 percent of P, less than or equal to 0.030 percent of S, 11.0 to 13.5 percent of Cr, less than or equal to 0.15 percent of Ni, less than or equal to 0.020 percent of N, and the balance of Fe and inevitable impurities; the content of C and Si in the second molten steel is 0.006-0.010 percent and 0.40-1.00 percent.
According to the preparation method of the low-chromium soft magnetic stainless steel, the third molten steel comprises the following components in percentage by weight: less than or equal to 0.015 percent of C, 0.4 to 1.0 percent of Si, 0.15 to 0.30 percent of Mn, less than or equal to 0.030 percent of P, less than or equal to 0.005 percent of S, 11.0 to 13.5 percent of Cr, less than or equal to 0.20 percent of Ni, 0.12 to 0.30 percent of Ti, less than or equal to 0.020 percent of N, and the balance of Fe and inevitable impurities.
In the preparation method of the low-chromium soft magnetic stainless steel, in the refining process of the LF furnace, the bottom blowing gas strength is 100-minus 200L/min, the stirring time is 3min, and the tapping temperature is controlled to be 1570-minus 1585 ℃.
In the preparation method of the low-chromium soft magnetic stainless steel, in the hot rolling procedure, the heating and heat preservation temperature is 1100-.
In the preparation method of the low-chromium soft magnetic stainless steel, in the annealing and pickling process, the annealing temperature is 850-950 ℃, the TV is 170-210, the sulfuric acid concentration is 200-300g/L, the nitric acid concentration is 60-120g/L, and the hydrofluoric acid concentration is less than or equal to 7 g/L.
In the preparation method of the low-chromium soft magnetic stainless steel, in the cold rolling procedure, the cold rolling reduction is 55-75%; in the bright annealing process, the annealing temperature is 900-980 ℃, and the TV is 20-50.
In a third aspect, the invention provides an application of the low-chromium soft magnetic stainless steel in preparing an electromagnetic valve body.
The technical scheme of the invention has the following beneficial effects:
(1) the low-chromium soft magnetic stainless steel has low raw material cost, good corrosion resistance and good electromagnetic property;
(2) the low-chromium soft magnetic stainless steel has the advantages of increased grain size and lower surface roughness and coercive force, wherein the coercive force can be reduced to be less than or equal to 120A/m;
(3) the component design of the invention adopts the addition of Ti element to be combined with C, N element in preference to Cr element, thereby avoiding local chromium depletion and improving the corrosion resistance of the material;
(4) the invention provides a preparation method of low-chromium soft magnetic stainless steel, which can effectively avoid oxidation residue by bright annealing treatment of cold-rolled stainless steel and reduce the chromium content in the stainless steel by utilizing the influence of low surface roughness on corrosion resistance;
(5) the low-chromium soft magnetic stainless steel and the product produced by the preparation method thereof can replace pure iron to manufacture electromagnetic valve bodies of electronic products in household cars, radio industry and the like.
Drawings
Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention.
Fig. 1 is a graph showing the relationship between the coercive force and the grain size of the soft magnetic stainless steel.
Detailed Description
The present invention will be described in detail with reference to the following embodiments in order to fully understand the objects, features and effects of the invention. The process of the present invention employs conventional methods or apparatus in the art, except as described below. The following noun terms have meanings commonly understood by those skilled in the art unless otherwise specified.
The terms "the," "said," "an," and "an" as used herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item. The terms "preferred", "further preferred", and the like, refer to embodiments of the invention that may provide certain benefits under certain circumstances. However, other embodiments may be preferred, under the same or other circumstances. Furthermore, the recitation of one or more embodiments does not imply that other embodiments are not useful, nor is it intended to exclude other embodiments from the scope of the invention.
When a range of values is disclosed herein, the range is considered to be continuous and includes both the minimum and maximum values of the range, as well as each value between such minimum and maximum values. Further, when a range refers to an integer, each integer between the minimum and maximum values of the range is included. Further, when multiple range-describing features or characteristics are provided, the ranges may be combined. In other words, unless otherwise indicated, all ranges disclosed herein are to be understood to encompass any and all subranges subsumed therein.
Specifically, according to a first aspect of the present invention, there is provided a low-chromium soft magnetic stainless steel comprising, in weight percent: c is less than or equal to 0.015 percent; 0.4 to 1.0 percent of Si; 0.15 to 0.30 percent of Mn; p is less than or equal to 0.030 percent; s is less than or equal to 0.005 percent; 11.0 to 13.5 percent of Cr; ni is less than or equal to 0.20 percent; 0.12 to 0.30 percent of Ti; n is less than or equal to 0.020%; the balance being Fe and unavoidable impurities.
The invention optimizes the component design, ensures lower C, N content by adding proper amount of Ti element, utilizes the preferential reaction of Ti with C, N in steel, and controls O, S, P and other impurity elements in steel to ensure the corrosivity and good processability of stainless steel.
Specifically, in the composition design of the present invention:
C. n: the solubility of carbon and nitrogen in ferritic stainless steel is very low, so that carbide (Cr, Fe) is inevitably precipitated during high-temperature heating and subsequent cooling 23 C 6 And (Cr, Fe) 7 C 3 Etc.) and nitrides (CrN and Cr 2 N) to create Cr-lean regions, resulting in a significant reduction in the corrosion resistance of these regions; meanwhile, the coercive force of the alloy is improved and the soft magnetic performance of the alloy is deteriorated due to the increase of the content of the carbon element. Therefore, the invention limits the content of C to less than or equal to 0.015 percent (preferably less than or equal to 0.010 percent), limits the content of N to less than or equal to 0.020 percent (less than or equal to 0.010 percent) and ensures the content as low as possible.
Cr: chromium is an alloying element that imparts a ferritic structure to ferritic stainless steels and has good corrosion resistance. The corrosion resistance is the biggest influence of Cr on the performance of the ferritic stainless steel, which is mainly reflected in the improvement of the performance of the steel against oxidation media and acid chloride media, and the chromium can rapidly generate chromium oxide (Cr) on the surface of the stainless steel in the oxidation media 2 O 3 ) And (5) passivating the film. Therefore, the present invention limits the Cr content to 11.0% to 13.5% (preferably 11.0% to 12.50%).
Mn: manganese is added as a deoxidizing element, and if the content is too low, the purity of the steel is not favorable, and if the content is too high, the cost is increased. Therefore, the present invention limits the Mn content to: mn 0.15% -0.30% (preferably 0.15% -0.25%).
Si: the silicon element can obviously improve the soft magnetic property of the alloy, but the silicon element content is too high, which has certain influence on the improvement of the surface quality of the product and is easy to form a composite oxide which is difficult to remove on the surface. Therefore, the present invention limits the Si content to: 0.4% -1.0% (preferably 0.40% -0.6%).
Ti: titanium is a powerful carbonitride generating element, and contributes to the improvement of corrosion resistance. Ti and N are combined to form TiN, the isometric crystal proportion can be increased, the forming performance is improved, but the Ti content is too high to be beneficial to the later-stage grain coarsening, so the Ti content is limited to 0.12-0.30% (preferably 0.15% -0.25%).
P, S: phosphorus and sulfur are harmful elements, and the lower the content, the better.
Ni: the nickel element is an austenite forming element, and in this steel grade, the nickel element is controlled only as a residual element, and since the nickel element has an influence on the saturation magnetization of this steel, the content thereof is limited to not more than 0.20%.
In the invention, the specific components in the contents exert a synergistic effect, so that the corrosion resistance and the electromagnetic property of the low-chromium soft magnetic stainless steel are improved, and the cost and the coercive force of the raw materials are reduced.
According to a second aspect, the present invention provides a method for preparing a low chromium soft magnetic stainless steel, comprising:
(1) smelting molten iron by adopting a converter, and introducing inert gas in the whole smelting process to obtain first molten steel;
(2) introducing the first molten steel into a VOD furnace, and performing vacuum decarburization and denitrification treatment to obtain second molten steel;
(3) introducing the second molten steel into an LF furnace, and adding ferrotitanium to adjust the titanium content to obtain third molten steel;
(4) and sequentially carrying out continuous casting, coping, hot rolling, annealing and pickling, cold rolling and bright annealing on the third molten steel to finally obtain the low-chromium soft magnetic stainless steel.
According to the preparation method of the low-chromium soft magnetic stainless steel, the stainless steel after cold rolling is subjected to bright annealing treatment, so that oxidation residues can be effectively avoided, and meanwhile, the influence of low surface roughness on corrosion resistance is utilized, so that the content of chromium in the stainless steel is reduced.
In some preferred embodiments, the method for preparing the low chromium soft magnetic stainless steel of the present invention comprises:
(1) and smelting the molten iron by adopting a converter, and introducing inert gas in the whole smelting process to obtain first molten steel.
Preferably, the molten iron is pretreated by a blast furnace before being introduced into the converter, and P is controlled to be less than or equal to 0.010 wt% and S is controlled to be less than or equal to 0.035 wt%.
Further preferably, the first molten steel comprises, by weight: 0.20 to 0.30 percent of C, 0.05 to 0.15 percent of Si, 0.20 to 0.30 percent of Mn, less than or equal to 0.025 percent of P, less than or equal to 0.030 percent of S, 11.0 to 13.5 percent of Cr, less than or equal to 0.15 percent of Ni, less than or equal to 0.020 percent of N, and the balance of Fe and inevitable impurities.
Preferably, the inert gas is argon.
Further preferably, in the smelting process of the converter, the tapping temperature is controlled to 1650-.
(2) And introducing the first molten steel into a VOD furnace, and performing vacuum decarburization and denitrification treatment to obtain second molten steel.
Preferably, in the refining process of the VOD furnace, the arrival temperature of the first molten steel introduced into the VOD furnace is controlled to be more than or equal to 1600 ℃, the arrival slag thickness is less than or equal to 50mm, the vacuum degree in the VOD furnace is less than or equal to 3mbar, and the stirring time is more than or equal to 12 min.
Optionally, during the refining process of the VOD furnace, a proper amount of Al can be added into the furnace according to the requirement.
Refining by a VOD furnace to ensure that the content of C and Si in the second molten steel is 0.006-0.010 wt% and 0.40-1.00 wt%.
(3) And introducing the second molten steel into an LF furnace, and adding ferrotitanium to adjust the titanium content to obtain third molten steel.
Preferably, in the refining process of the LF furnace, stirring for 3min with the bottom blowing gas supply strength of 100-200L/min can be carried out to ensure that the molten steel is not exposed, and weak stirring with the bottom blowing gas supply strength of 80-100L/min can be carried out, wherein the weak stirring time is more than or equal to 15min, and the tapping temperature is controlled to 1570-1585 ℃.
Further preferably, during single pouring, the tapping temperature is controlled to be 1605-; and during continuous casting, the tapping temperature is controlled to be 1600-.
Specifically, the second molten steel is introduced into an LF furnace, the sulfur content of the molten liquid in the LF furnace is adjusted, and refining in the LF furnace is controlled, so that the third molten steel comprises the following chemical components in percentage by weight: : less than or equal to 0.015 percent of C, 0.4 to 1.0 percent of Si, 0.15 to 0.30 percent of Mn, less than or equal to 0.030 percent of P, less than or equal to 0.005 percent of S, 11.0 to 13.5 percent of Cr11, less than or equal to 0.20 percent of Ni, 0.12 to 0.30 percent of Ti, less than or equal to 0.020 percent of N, and the balance of Fe and inevitable impurities.
(4) And sequentially carrying out continuous casting, coping, hot rolling, annealing and pickling, cold rolling and bright annealing on the third molten steel to finally obtain the low-chromium soft magnetic stainless steel.
Preferably, the temperature of the cast steel is controlled to be 1540-1560 ℃ during the continuous casting process, so that the problems that the supercooling degree is too small when the temperature is too high, the rapid solidification of the casting blank is not facilitated, and the floating of inclusions in the molten steel casting process is not facilitated due to too low temperature are solved.
Wherein, in the grinding process, each surface of the stainless steel plate blank is ground, and the visible defects on the surface are ground completely.
In the hot rolling step, the stainless steel slab is heated and held at a predetermined temperature and is rolled to a predetermined thickness. Preferably, the heating and heat-preserving temperature of the hot-rolled coil is 1100-. The heating and heat preservation time is 9-12min/10mm in thickness so as to meet the requirement of uniform internal and external temperatures of the casting blank.
Further preferably, after the hot rolling process is finished, the coiling temperature is 600-.
Wherein, in the annealing and pickling process, the annealing temperature is 850-950 ℃, the TV is 170-210, the sulfuric acid concentration is 200-300g/L, the nitric acid concentration is 60-120g/L, and the hydrofluoric acid concentration is less than or equal to 7 g/L. Therefore, on one hand, the hot rolled strip structure is eliminated through annealing, and the matrix is subjected to recovery recrystallization; on the other hand, the influence of rolling lubrication is removed by pickling with sulfuric acid, and the surface oxide is removed by pickling with a mixture of nitric acid and hydrofluoric acid.
Wherein, in the cold rolling process, the cold rolling reduction is 55-75%.
Wherein, in the bright annealing process, the annealing temperature is 900-980 ℃, and the TV is 20-50. The Cr element is an essential element in the stainless steel, the higher the content is, the higher the corrosion resistance is, the bright annealing process is adopted, the oxide residue on the surface of the stainless steel is reduced, the surface roughness is reduced, and the surface advantage is utilized to replace the action of the chromium element, so that the corrosion resistance is improved.
In the art, an important index for measuring the electromagnetic performance of soft magnetic materials is the coercive force Hc, and the lower the value of the coercive force Hc, the better the electromagnetic performance. The coercivity Hc of the soft magnetic material is related to the grain size. Fig. 1 shows a graph of the relationship between the coercive force and the grain size of the soft magnetic stainless steel, in which the ordinate represents the coercive force Hc and the abscissa represents the grain size. As can be seen from fig. 1, the larger the grain size within a certain range, the lower the coercive force Hc corresponding thereto, and the more excellent the electromagnetic performance.
Through detection, the low-chromium soft magnetic stainless steel produced by the method has the advantages of increased grain size and lower surface roughness and coercive force, wherein the coercive force can be reduced to be less than or equal to 120A/m.
It should be noted that parameters which are not noted in the processes of smelting, continuous casting, coping, rolling and annealing in the preparation method of the low-chromium soft magnetic stainless steel of the present invention can be performed according to the conventional method, and the present invention is not limited specifically herein.
The low-chromium soft magnetic stainless steel is combined with C, N element in preference to Cr element by adding Ti element, so that local chromium deficiency is avoided, the corrosion resistance of the material is improved, and meanwhile, a bright annealing process is adopted to reduce the surface roughness and oxidation residue, thereby providing good surface quality for annealing of the processed product in a protective atmosphere; in the aspect of improving magnetism, the annealing process is adopted to improve the product performance, and the method replaces the prior art that the alloy component Si element is used to improve the product performance.
According to a third aspect, the invention also provides the application of the low-chromium soft magnetic stainless steel in preparing the electromagnetic valve body.
Preferably, the low-chromium soft magnetic stainless steel can be used for producing electromagnetic valve bodies of industrial products such as automobile electronic igniters and the like.
Examples
The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention. Experimental procedures without specifying specific conditions in the following examples were carried out according to conventional methods and conditions.
Firstly, a step of pretreating blast furnace molten iron, wherein P is controlled to be less than or equal to 0.010 percent and S is controlled to be less than or equal to 0.035 percent in the molten iron pretreatment process.
Next, a multi-stage smelting step, which comprises:
firstly, smelting in a converter, wherein pretreated molten iron is introduced into the converter, argon is introduced in the whole smelting process of the converter, and the smelting in the converter is controlled, so that the generated first molten steel comprises the following chemical components in percentage by weight: c: 0.20-0.30%, Si: 0.05-0.15%, Mn: 0.20 to 0.30 percent of steel, less than or equal to 0.025 percent of P, less than or equal to 0.030 percent of S, 11.0 to 13.5 percent of Cr, less than or equal to 0.15 percent of Ni, less than or equal to 0.020 percent of N, and the balance of Fe and inevitable impurities, wherein the tapping temperature is controlled at 1650-1685 ℃ and the slag thickness is less than or equal to 50mm in the smelting process of the furnace.
And secondly, refining in a VOD furnace, wherein the first molten steel is introduced into the VOD furnace, vacuum decarburization and denitrification treatment are carried out, a proper amount of Al is added according to the requirement, and the refining in the VOD furnace is controlled so that the generated second molten steel comprises the following chemical components in percentage by weight: c: 0.006-0.010%, Si: 0.40-1.00%, wherein the arrival temperature of the first molten steel introduced into the VOD furnace is controlled to be more than or equal to 1600 ℃, the arrival slag thickness is less than or equal to 50mm, the vacuum degree in the VOD furnace is less than or equal to 3mbar, and the stirring time is more than or equal to 12 min.
And finally, refining in an LF (ladle furnace), wherein the second molten steel is introduced into the LF, the sulfur content of the molten liquid in the LF is adjusted, the refining in the LF is controlled, a titanium alloy is added, and the chemical components of the molten steel are finely adjusted so that the generated third molten steel comprises the following chemical components in percentage by weight as shown in embodiment 1, embodiment 2 and embodiment 3 in Table 1. Wherein, in the LF furnace refining, the stirring can be carried out for 3min at the bottom blowing gas supply intensity of 100-.
And continuously casting the third molten steel into a stainless steel plate blank, wherein the steel casting temperature is 1540-.
And grinding the stainless steel plate blank, wherein each surface of the stainless steel plate blank is ground for 2 times.
And a stainless steel plate blank hot rolling step, wherein the heating and heat preservation temperature is controlled to be 1100-.
Annealing and pickling stainless steel hot rolled coils, wherein the annealing temperature is 850-950 ℃, the TV is controlled at 170-210, the concentration of sulfuric acid is controlled at 200-300g/L, the concentration of nitric acid is controlled at 60-120g/L, and the concentration of hydrofluoric acid is controlled at: less than or equal to 7 g/L.
And (3) cold rolling the stainless steel hot rolled coil, controlling the cold rolling reduction rate to be 55-75%, and rolling the stainless steel hot rolled coil into a stainless steel cold rolled coil with the thickness of 0.5-3.0 mm.
And finally, a stainless steel cold-rolled coil annealing step, wherein the annealing temperature is controlled to be 900-980 ℃, the TV is controlled to be 20-50, and the stainless steel cold-rolled coil is subjected to bright annealing treatment to obtain the expected stainless steel cold-rolled coil product, and the physical and chemical properties of the stainless steel cold-rolled coil product are shown in the table 2 in embodiment 1, embodiment 2 and embodiment 3.
Table 1 shows chemical compositions of a low-chromium soft magnetic stainless steel according to various embodiments of the present invention, and chemical compositions of an existing low-chromium soft magnetic stainless steel as a comparative example.
TABLE 1 Components and contents (wt%) of low-chromium soft magnetic stainless steels in examples and comparative examples
Example 1, example 2 and example 3 in table 1 are all low chromium soft magnetic stainless steel materials according to examples of the present invention, which are all produced by the method for preparing the low chromium soft magnetic stainless steel according to the present invention. Comparative example 1 is a commercially available prior art material, designation KM-31. Comparative example 2 is a soft magnetic stainless steel with publication number CN 111471918A.
Table 2 further shows the comparison of the properties and the manufacturing costs of the low chromium soft magnetic stainless steel according to the example of the present invention and the existing soft magnetic stainless steel KM-31 as comparative example 1 and the soft magnetic stainless steel with publication No. CN111471918A as comparative example 2.
TABLE 2 coercive force of low-chromium soft magnetic stainless steel in each example and comparative example
| Coercive force Hc/(A/m) | Material manufacturing cost per ton steel | |
| Example 1 | 89 | 8209 |
| Example 2 | 110 | 8168 |
| Example 3 | 103 | 8198 |
| Comparative example 1 | 323 | - |
| Comparative example 2 | 101 | 8638 |
As can be seen from Table 2, the coercive force of the low-chromium soft magnetic stainless steel material of the invention is 89-110A/m, which is much lower than 323A/m of KM-31, and the manufacturing cost of the low-chromium soft magnetic stainless steel material of the invention is lower than that of the soft magnetic stainless steel with publication No. CN 111471918A. Therefore, the soft magnetic stainless steel material has more excellent electromagnetic performance and lower cost.
Wherein, the cost of the comparative example 2 in the table 2 is measured and calculated by B3805207 heat smelting components, and the cost of the cold plate is measured and calculated by adopting the same manufacturing process.
The present invention has been disclosed in the foregoing in terms of preferred embodiments, but it will be understood by those skilled in the art that these embodiments are merely illustrative of the present invention and should not be construed as limiting the scope of the present invention. It should be noted that all changes and substitutions that are equivalent to these embodiments are deemed to be within the scope of the claims of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined in the claims.
Claims (10)
1. A low-chromium soft magnetic stainless steel is characterized by comprising the following components in percentage by weight: c is less than or equal to 0.015 percent; 0.4 to 1.0 percent of Si; 0.15 to 0.30 percent of Mn; p is less than or equal to 0.030 percent; s is less than or equal to 0.005 percent; 11.0 to 13.5 percent of Cr; ni is less than or equal to 0.20 percent; 0.12 to 0.30 percent of Ti; n is less than or equal to 0.020%; the balance being Fe and unavoidable impurities.
2. The low chromium soft magnetic stainless steel according to claim 1, comprising, in weight percent: c is less than or equal to 0.010 percent; 0.40 to 0.60 percent of Si; 0.15 to 0.25 percent of Mn; p is less than or equal to 0.025 percent; s is less than or equal to 0.001 percent; 11.0 to 12.50 percent of Cr; ni is less than or equal to 0.20 percent; 0.15 to 0.25 percent of Ti; n is less than or equal to 0.010 percent; the balance being Fe and unavoidable impurities.
3. A method for producing a low chromium soft magnetic stainless steel according to claim 1 or 2, comprising:
(1) smelting molten iron by adopting a converter, and introducing inert gas in the whole smelting process to obtain first molten steel;
(2) introducing the first molten steel into a VOD furnace, and performing vacuum decarburization and denitrification treatment to obtain second molten steel;
(3) introducing the second molten steel into an LF furnace, and adding ferrotitanium to adjust the titanium content to obtain third molten steel;
(4) and sequentially carrying out continuous casting, coping, hot rolling, annealing and pickling, cold rolling and bright annealing on the third molten steel to finally obtain the low-chromium soft magnetic stainless steel.
4. The method of preparing a low chromium soft magnetic stainless steel according to claim 3, wherein the first molten steel comprises, in weight percent: 0.20 to 0.30 percent of C, 0.05 to 0.15 percent of Si, 0.20 to 0.30 percent of Mn, less than or equal to 0.025 percent of P, less than or equal to 0.030 percent of S, 11.0 to 13.5 percent of Cr, less than or equal to 0.15 percent of Ni, less than or equal to 0.020 percent of N, and the balance of Fe and inevitable impurities; the content of C and Si in the second molten steel is 0.006-0.010 percent and 0.40-1.00 percent.
5. The method of preparing a low chromium soft magnetic stainless steel according to claim 3, wherein the third molten steel comprises, in weight percent: less than or equal to 0.015 percent of C, 0.4 to 1.0 percent of Si, 0.15 to 0.30 percent of Mn, less than or equal to 0.030 percent of P, less than or equal to 0.005 percent of S, 11.0 to 13.5 percent of Cr, less than or equal to 0.20 percent of Ni, 0.12 to 0.30 percent of Ti, less than or equal to 0.020 percent of N, and the balance of Fe and inevitable impurities.
6. The method for preparing a low-chromium soft magnetic stainless steel as claimed in claim 3, wherein in the refining process of the LF furnace, the strength of bottom blowing gas is 100-200L/min, the stirring time is 3min, and the tapping temperature is controlled to be 1570-1585 ℃.
7. The method for preparing a low-chromium soft magnetic stainless steel as claimed in claim 3, wherein in the hot rolling process, the heating and heat preservation temperature is 1100-.
8. The method for preparing a low-chromium soft magnetic stainless steel as claimed in claim 3, wherein in the annealing and pickling process, the annealing temperature is 850-.
9. A method for producing a low-chromium soft magnetic stainless steel according to claim 3, wherein in the cold rolling process, a cold rolling reduction is 55 to 75%; in the bright annealing process, the annealing temperature is 900-980 ℃, and the TV is 20-50.
10. Use of the low chromium soft magnetic stainless steel according to any one of claims 1 to 9 for the manufacture of a solenoid valve body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210339735.1A CN114836684A (en) | 2022-04-01 | 2022-04-01 | Low-chromium soft magnetic stainless steel and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210339735.1A CN114836684A (en) | 2022-04-01 | 2022-04-01 | Low-chromium soft magnetic stainless steel and preparation method and application thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114836684A true CN114836684A (en) | 2022-08-02 |
Family
ID=82564352
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210339735.1A Pending CN114836684A (en) | 2022-04-01 | 2022-04-01 | Low-chromium soft magnetic stainless steel and preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114836684A (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62247027A (en) * | 1986-04-19 | 1987-10-28 | Nippon Steel Corp | Production of chromium-containing steel products having excellent corrosion resistance |
| JPH07233452A (en) * | 1993-12-27 | 1995-09-05 | Sumitomo Metal Ind Ltd | Ferritic stainless steel excellent in magnetic property |
| JPH1036950A (en) * | 1996-07-25 | 1998-02-10 | Nisshin Steel Co Ltd | Soft magnetic stainless steel having high magnetic flux density |
| US20160333439A1 (en) * | 2014-01-08 | 2016-11-17 | Jfe Steel Corporation | Ferritic stainless steel and production method therefor |
| CN111471918A (en) * | 2020-03-30 | 2020-07-31 | 山西太钢不锈钢股份有限公司 | Soft magnetic stainless steel and method for manufacturing soft magnetic stainless steel wire |
| CN113025872A (en) * | 2021-02-01 | 2021-06-25 | 广西柳钢华创科技研发有限公司 | Chromium-manganese-nickel-nitrogen austenitic stainless steel and manufacturing method thereof |
-
2022
- 2022-04-01 CN CN202210339735.1A patent/CN114836684A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62247027A (en) * | 1986-04-19 | 1987-10-28 | Nippon Steel Corp | Production of chromium-containing steel products having excellent corrosion resistance |
| JPH07233452A (en) * | 1993-12-27 | 1995-09-05 | Sumitomo Metal Ind Ltd | Ferritic stainless steel excellent in magnetic property |
| JPH1036950A (en) * | 1996-07-25 | 1998-02-10 | Nisshin Steel Co Ltd | Soft magnetic stainless steel having high magnetic flux density |
| US20160333439A1 (en) * | 2014-01-08 | 2016-11-17 | Jfe Steel Corporation | Ferritic stainless steel and production method therefor |
| CN111471918A (en) * | 2020-03-30 | 2020-07-31 | 山西太钢不锈钢股份有限公司 | Soft magnetic stainless steel and method for manufacturing soft magnetic stainless steel wire |
| CN113025872A (en) * | 2021-02-01 | 2021-06-25 | 广西柳钢华创科技研发有限公司 | Chromium-manganese-nickel-nitrogen austenitic stainless steel and manufacturing method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111575588B (en) | Martensite precipitation hardening stainless steel and preparation method and application thereof | |
| CN111809107A (en) | Hot-dip galvanized high-strength IF steel for Ti-series ton barrel and manufacturing method thereof | |
| CN110079731B (en) | 260 MPa-grade cold-rolled steel plate for enamel and production method thereof | |
| CN113846260B (en) | Production method of high-strength steel plate for engineering machinery | |
| CN113403550B (en) | High-plasticity fatigue-resistant cold-rolled hot-galvanized DH1180 steel plate and preparation method thereof | |
| WO2022228216A1 (en) | Steel for high-temperature carburized gear shaft and manufacturing method for steel | |
| CN110527923B (en) | High-yield-ratio structural steel for 600 MPa-grade automobile body and production method thereof | |
| CN111793777A (en) | 1000 MPa-level hot-rolled high-strength corrosion-resistant dual-phase steel plate and preparation method thereof | |
| CN111809108A (en) | Hot-galvanized high-strength IF steel for 400 MPa-grade car front fender and manufacturing method thereof | |
| WO2019029533A1 (en) | Cast steel, preparation method for cast steel and use of cast steel | |
| CN109097681A (en) | A kind of high intensity is low to be mingled with autobody sheet and its continuous casting process electromagnetic agitation technique | |
| CN110093563B (en) | Enamel cold-rolled steel plate for deep drawing and production method thereof | |
| CN114657459B (en) | Nitrogen-vanadium-titanium-niobium rare earth microalloyed high-strength deep-drawing cold-rolled steel plate and production method thereof | |
| EP3821041A1 (en) | Process for producing a high strength cold-rolled and heat-treated steel strip and product produced thereby | |
| CN115679223A (en) | Novel high-yield-ratio cold-rolled DH980 steel and preparation method thereof | |
| CN111424221B (en) | Stainless steel plate for lamination and manufacturing method thereof | |
| CN114836684A (en) | Low-chromium soft magnetic stainless steel and preparation method and application thereof | |
| CN113462960A (en) | Preparation method of 340 MPa-grade niobium-containing hot-galvanized high-strength IF steel | |
| CN107829025B (en) | thin-gauge dual-phase steel with good hole expanding performance and processing method thereof | |
| WO2023241546A1 (en) | Highly formable and easily phosphated high-manganese cold-rolled steel plate having tensile strength of 1000-1600 mpa, and manufacturing method therefor | |
| CN116043122B (en) | 600 MPa-grade acid-pickled dual-phase steel with high reaming performance and capable of being directly hot-packed and production method thereof | |
| CN112795837B (en) | 1300Mpa high-toughness cold-formed steel plate and production method thereof | |
| WO2023246941A1 (en) | Automotive structural steel having a yield strength of ≥1000 mpa and manufacturing method therefor | |
| WO2023246898A1 (en) | High-plasticity steel and manufacturing method therefor | |
| WO2024032528A1 (en) | Hot stamped part having excellent low-temperature brittleness resistance and manufacturing method therefor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |