A high magnetic induction oriented silicon steel and its manufacturing method and product

Abstract

The present application provides a high magnetic induction oriented silicon steel and a manufacturing method and product thereof, wherein the high magnetic induction oriented silicon steel, in terms of mass percentage, is composed of the following components: C: 0.025% to 0.06%; Si: 2.9% to 3.7%; Mn: 0.08% to 0.3%; Als: 0.01% to 0.035%; Cu: 0.1% to 0.6%; N: 0.006% to 0.012%; Sn: 0.01% to 0.1%; P: 0 to 0.03%; S: 0 to 0.015%; the rest is iron and other unavoidable impurities. The high magnetic induction oriented silicon steel can be prepared using a medium temperature slab heating process, has lower iron loss and higher magnetic polarization intensity, and meets the national standard for the performance requirements of high magnetic induction oriented silicon steel.

Description

Technical Field

[0001] The present application relates to the technical field of steel production, and in particular to a high magnetic induction oriented silicon steel and a manufacturing method and product thereof. Background Art

[0002] High-performance oriented silicon steel is the "crown" of steel industry products and is the core material for manufacturing ultra-high voltage AC / DC transformers, high-efficiency and energy-saving distribution transformers, converter valve saturated reactors and other power equipment.

[0003] Oriented silicon steel can be divided into high magnetic induction oriented silicon steel (HiB) and common oriented silicon steel (CGO) according to its performance; high magnetic induction oriented silicon steel (HiB) can be divided into high temperature high magnetic induction oriented silicon steel (slab heating temperature is greater than 1350℃) and low temperature high magnetic induction oriented silicon steel (slab heating temperature is less than 1200℃) according to the slab heating temperature range; medium temperature oriented silicon steel (slab heating temperature is 1250-1320℃) generally has low magnetic induction, and CGO is generally produced using medium temperature slab heating process. There is no report on the production of high magnetic induction oriented silicon steel using medium temperature slab heating process.

[0004] Therefore, it is necessary to provide a high magnetic induction oriented silicon steel that can be produced using a medium temperature slab heating process. Summary of the invention

[0005] The present application provides a high magnetic induction oriented silicon steel and a manufacturing method and product thereof. The high magnetic induction oriented silicon steel can be prepared using a medium-temperature slab heating process, has lower iron loss and higher magnetic polarization intensity, and meets the national standard for the performance requirements of high magnetic induction oriented silicon steel.

[0006] In a first aspect, the present application provides a high magnetic induction oriented silicon steel, which is composed of the following components in terms of mass percentage:

[0007] C: 0.025%~0.06%;

[0008] Si: 2.9%~3.7%;

[0009] Mn: 0.08%~0.3%;

[0010] Als: 0.01%~0.035%;

[0011] Cu: 0.1%~0.6%;

[0012] N: 0.006%~0.012%;

[0013] Sn: 0.01%~0.1%;

[0014] P: 0~0.03%;

[0015] S: 0~0.015%;

[0016] The rest is iron and other inevitable impurities.

[0017] In the technical solution of the present application, by adjusting the components and their mass percentages in high magnetic induction oriented silicon steel, Cu2S is used as the main inhibitor to make it suitable for production by medium temperature slab heating process, and a certain amount of Sn is added as an auxiliary inhibitor. Sn can be segregated on the grain boundaries during the secondary recrystallization annealing process, hindering the normal growth of the primary grains, and promoting the preferential growth of Goss grains, thereby reducing iron loss and improving magnetic induction, and obtaining high magnetic induction oriented silicon steel.

[0018] In some embodiments of the present application, the following components are used in percentage by mass:

[0019] C: 0.03%~0.05%;

[0020] Si: 3% to 3.5%;

[0021] Mn: 0.08%~0.25%;

[0022] Als: 0.01%~0.03%;

[0023] Cu: 0.3%~0.6%;

[0024] N: 0.006%~0.012%;

[0025] Sn: 0.01%~0.04%;

[0026] P: 0~0.03%;

[0027] S: 0~0.015%;

[0028] The rest is iron and other inevitable impurities.

[0029] In some embodiments of the present application, the thickness of the high magnetic induction oriented silicon steel is 0.15-0.3 mm.

[0030] In some embodiments of the present application, the core loss P of the high magnetic induction oriented silicon steel is 1.7 / 50 ≤1W / kg.

[0031] In some embodiments of the present application, the magnetic polarization intensity J of the high magnetic induction oriented silicon steel is 800 ≥1.88T.

[0032] In a second aspect, the present application provides a method for preparing high magnetic induction oriented silicon steel, comprising the following steps:

[0033] S10 provides slabs;

[0034] S20: heating the slab to obtain a heated slab;

[0035] S30 Descaling, rough rolling and finish rolling the heated slab to obtain a hot rolled steel plate;

[0036] S40: cooling the hot-rolled steel sheet to a coiling temperature, coiling, pickling, primary cold rolling, decarburization annealing, secondary cold rolling, and high-temperature annealing to obtain high magnetic induction oriented silicon steel;

[0037] The cooling specifically includes: cooling the hot-rolled steel plate to 750-850°C at 150-400°C / s, and then cooling to the coiling temperature at 50-100°C / s;

[0038] The high magnetic induction oriented silicon steel is composed of the following components by mass percentage:

[0039] C: 0.025%~0.06%;

[0040] Si: 2.9%~3.7%;

[0041] Mn: 0.08%~0.3%;

[0042] Als: 0.01%~0.035%;

[0043] Cu: 0.1%~0.6%;

[0044] N: 0.006%~0.012%;

[0045] Sn: 0.01%~0.1%;

[0046] P: 0~0.03%;

[0047] S: 0~0.015%;

[0048] The rest is iron and other inevitable impurities.

[0049] The technical solution of the present application is a further improvement on the preparation method of oriented silicon steel, mainly in that an ultra-fast cooling process is used to quickly cool the hot-rolled steel plate obtained by finish rolling, thereby reducing the temperature of the peak precipitation of the two-phase particles, refining the size of the two-phase particles, and making the distribution more uniform and the inhibitory force stronger; at the same time, due to the rapid cooling, the degree of microstructure recovery and recrystallization of the hot-rolled steel plate can be shortened, further reducing iron loss and improving magnetic induction.

[0050] In some embodiments of the present application, step S20 specifically includes:

[0051] The slab is heated at 1280-1320° C. for more than 200 minutes to obtain a heated slab.

[0052] In some embodiments of the present application, in the step S30, the final rolling temperature of the finish rolling is 920-1050°C.

[0053] In some embodiments of the present application, in the step S40, the coiling temperature is 450-620°C.

[0054] In a third aspect, the present application provides a product manufactured by processing the high magnetic steel oriented silicon steel according to any embodiment of the first aspect or the high magnetic steel oriented silicon steel manufactured by the manufacturing method according to any embodiment of the second aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0056] Figure 1 This is the electron microscope morphology of the two-phase particles in Example 1.

[0057] Figure 2 This is the electron microscope morphology of the two-phase particles in Example 3.

[0058] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0059] The various embodiments or implementation schemes in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments.

[0060] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the implementation or examples are included in at least one implementation or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same implementation or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more implementations or examples in a suitable manner.

[0061] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0062] The inventors have discovered that in the prior art, high magnetic induction oriented silicon steel is mainly obtained through a high temperature slab heating process or a low temperature slab heating process.

[0063] In the high-temperature slab heating process, MnS and AlN are mainly used as inhibitors in oriented silicon steel. However, in the continuous casting process of the slab, due to the slow solidification and subsequent cooling of the cast slab, the second phase ions such as MnS and AlN are coarsened to more than ten or even dozens of microns, which completely loses the effect of inhibiting grain growth. Therefore, the slab must be heated to 1350-1400℃ to fully dissolve the coarse MnS and AlN particles, and control their fine dispersed precipitation in the subsequent hot rolling and normalizing processes. However, its disadvantages are energy waste and reduced yield. At the same time, the serious slag accumulation in the heating furnace leads to a shortened furnace life.

[0064] In the low-temperature slab heating process, generally only a trace amount of aluminum is added during steelmaking, and nitriding treatment is performed after decarburization annealing to form an AlN inhibitor. However, the disadvantage of this method is that an additional nitriding annealing process is added, which prolongs the process flow. At the same time, the nitriding amount is not evenly distributed along the thickness direction, and a long period of heat preservation is required to promote the diffusion of nitrogen elements. The production efficiency is very low. In addition, after nitriding treatment, the nitrogen content in the oriented silicon steel increases significantly, which will increase the burden of subsequent purification annealing, and it is also easy for the brass texture to grow abnormally, deteriorating the magnetic properties.

[0065] The medium temperature slab heating process can overcome the shortcomings of the above-mentioned high temperature slab heating process and low temperature slab heating process, but the problem is that the magnetic induction of the prepared oriented silicon steel is low and cannot meet the requirements of the national standard GB / T 2521.2 for high magnetic induction oriented silicon steel.

[0066] In this regard, the inventors adjusted and designed the components and mass percentages in the oriented silicon steel, so that high magnetic induction oriented silicon steel that meets the requirements of GB / T 2521.2 can be prepared through a medium-temperature slab heating process.

[0067] In a first aspect, the present application provides a high magnetic induction oriented silicon steel, which is composed of the following components in terms of mass percentage:

[0068] C: 0.025%~0.06%;

[0069] Si: 2.9%~3.7%;

[0070] Mn: 0.08%~0.3%;

[0071] Als: 0.01%~0.035%;

[0072] Cu: 0.1%~0.6%;

[0073] N: 0.006%~0.012%;

[0074] Sn: 0.01%~0.1%;

[0075] P: 0~0.03%;

[0076] S: 0~0.015%;

[0077] The rest is iron and other inevitable impurities.

[0078] In the technical solution of the present application, by adjusting the components and their mass percentages in high magnetic induction oriented silicon steel, Cu2S is used as the main inhibitor to make it suitable for production by medium temperature slab heating process, and a certain amount of Sn is added as an auxiliary inhibitor. Sn can be segregated on the grain boundaries during the secondary recrystallization annealing process, hindering the normal growth of the primary grains, and promoting the preferential growth of Goss grains, thereby reducing iron loss and improving magnetic induction, and obtaining high magnetic induction oriented silicon steel.

[0079] The components and mass percentages of the high magnetic induction oriented silicon steel in the technical solution of the present application are described in detail below.

[0080] The carbon (C) content is set within the range of 0.025% to 0.06%:

[0081] The C content within 0.025% to 0.06% can make the steel plate contain at least 5% to 25% austenite phase during the hot rolling process and lay the foundation for the next production process. At the same time, carbon is an element that expands austenite. If the carbon content is too low, it may directly lead to imperfect organization, inaccurate orientation, high iron loss, and low magnetic induction intensity during the secondary recrystallization process. If the carbon content is too high, the decarburization process may be more difficult and the organization may be uneven, which will affect the perfection of the secondary recrystallization.

[0082] The silicon (Si) content is set in the range of 2.9% to 3.7%:

[0083] The Si content of 2.9% to 3.7% can significantly increase the resistivity, thereby reducing turbine loss and iron loss, and the silicon element is mainly an element that shrinks the austenite zone. However, when the silicon content is too high, the hot-rolled structure becomes coarse and uneven, and the precipitated inhibitors are large in size and small in number, which weakens the inhibitor's ability to inhibit primary recrystallization, making it difficult to cause secondary recrystallization, and ultimately making it difficult to directly process the material. When the silicon content is too low, it is impossible to obtain oriented silicon steel with low iron loss and high magnetic induction.

[0084] Manganese (Mn) content is set in the range of 0.08% to 0.3%:

[0085] Mn can form MnS with S, which can prevent the hot brittleness caused by the formation of low-melting-point FeS along the grain boundaries. Therefore, a certain amount of manganese should be ensured to improve the hot-rolled plasticity. Mn can also improve the hot-rolled plate structure and texture, and improve the magnetic properties. In the technical solution of the present application, since MnS has a high solid solution temperature and is not suitable as an inhibitor in the medium-temperature slab heating process, the Mn content is not easy to be too high, and its content is controlled within the range of 0.08% to 0.3%.

[0086] The acid-soluble aluminum (Als) content is set within the range of 0.01% to 0.035%:

[0087] Als includes AlN in steel and solid solution aluminum. The solid solution temperature of AlN is lower than that of MnS, and in the presence of Cu, its solid solution temperature will be reduced. Therefore, AlN can be used as an auxiliary inhibitor to improve the orientation and magnetic induction of steel. In addition, the role of aluminum is similar to that of silicon. It can increase the resistivity of silicon steel, reduce battery core loss, and reduce magnetic induction intensity. When the aluminum content reaches a certain amount, it will coarsen the grains and promote carbon graphitization. Aluminum can also reduce the oxygen content in steel and reduce magnetic aging. However, aluminum oxide in steel will deteriorate the magnetism. Therefore, the Als content is set in the range of 0.01% to 0.035%.

[0088] The copper (Cu) content is set in the range of 0.1% to 0.6%:

[0089] In the technical solution of this application, Cu is mainly combined with S to form Cu2S as an inhibitor, and its solid solution temperature is about 1250°C, which is significantly lower than the solid solution temperature of MnS and AlN. At the same time, the addition of Cu can also reduce the solid solution temperature of AlN, so the heating temperature of the slab can be significantly reduced. At the same time, the same sulfide can be precipitated in large quantities during the hot rolling stage, and normalization is not required, which simplifies the production process. However, excessive Cu will form (Mn, Cu) S particles during the hot rolling process, which increases the coercive force and hysteresis loss of silicon steel and makes the steel brittle. Therefore, the copper (Cu) content is set in the range of 0.1% to 0.6%.

[0090] The tin (Sn) content is set in the range of 0.01% to 0.1%:

[0091] Sn is a segregation element that can segregate at Cu2S particles, thereby inhibiting the coarsening of Cu2S, making it more finely dispersed, strengthening the inhibitor's inhibitory ability, reducing the precipitate interface energy, inhibiting the precipitate from Ostwald effect, and improving the orientation and magnetic properties of steel. However, excessive addition of Sn will deteriorate the bottom layer quality of steel. The inventors found that a higher content of Cu in steel can improve the bottom layer quality of steel. After comprehensive consideration, the tin (Sn) content is set within the range of 0.01% to 0.1%.

[0092] The nitrogen (N) content is set within the range of 0.006% to 0.012%:

[0093] Nitrogen is a harmful element. It can form fine AlN with aluminum to act as an auxiliary inhibitor. However, when the content is too high, the iron loss of oriented silicon steel will increase. At the same time, nitrogen is also an element that produces magnetic aging. Because the solubility of nitrogen in α-Fe is about 10 times lower than that of carbon at room temperature, nitrogen has a greater impact on aging than carbon. When the nitrogen content is too high, blistering is likely to occur after annealing, and the product will be scrapped. Therefore, the nitrogen (N) content is set within the range of 0.006% to 0.012%.

[0094] Phosphorus (P) content is set below 0.03%:

[0095] Phosphorus can increase ρ, reduce the γ zone, promote grain growth, and reduce iron loss. Phosphorus significantly increases hardness and improves punching properties. Phosphorus has the effect of hindering the precipitation and growth of carbides and reducing magnetic aging. However, if the phosphorus content is too high, especially when the carbon content is very low, the cold-worked parts will deteriorate and the products will become brittle. Therefore, it is necessary to set the phosphorus (P) content below 0.03%.

[0096] Sulfur (S) content is set below 0.015%:

[0097] Sulfur is a harmful element. Its main function is to form Cu2S with Cu as an inhibitor. It has been inhibiting the growth of primary recrystallized grains during high-temperature annealing and providing a driving force for the abnormal growth of Goss grains. However, an increase in sulfur content will lead to an increase in iron loss of oriented silicon steel. S in steel not only increases the hot brittleness of steel, but also destroys the uniformity of the steel structure in the form of sulfide inclusions, hinders the growth of ferrite grains during annealing, and increases the hysteresis loss of silicon steel sheets. Therefore, the sulfur (S) content needs to be set below 0.015%.

[0098] In the technical solution of the present application, the content of Mn and Al in oriented silicon steel is significantly reduced, and Cu2S with a lower solid solution temperature is used as the main inhibitor, so that Cu2S in the slab can be fully dissolved at 1280-1320°C, and fine and dispersed Cu2S particles are precipitated during the subsequent hot rolling and cooling process, thereby inhibiting grain growth. At the same time, the mass fraction of the inhibitor element is controlled. When the mass fraction is too high, Cu2S coarsening cannot inhibit grain growth. When the mass fraction is too low, the number of inhibitors precipitated is too small, and the primary grains are easy to grow, which is also not conducive to the occurrence of secondary recrystallization.

[0099] Although Cu2S has a low solid solution temperature, which is conducive to the use of a medium-temperature slab heating process, the problem is that its high-temperature stability is poor and it is not easy to coarsen during high-temperature annealing, resulting in it being difficult to obtain oriented silicon steel with high magnetic induction by using it alone as an inhibitor. Therefore, by controlling the content of Al and N and adding the segregated element Sn, the magnetic induction of the oriented silicon steel is improved by using Cu2S+AlN+Sn together as an inhibitor, and by controlling the mass percentage of the components, it can be fully dissolved under medium-temperature slab heating conditions, and can be aged at a suitable rate in the high temperature zone. While ensuring that the Goss grains undergo secondary recrystallization, the surrounding matrix remains small and stable, thereby obtaining a high magnetic induction oriented silicon steel with low iron loss.

[0100] In some embodiments of the present application, the following components are used in percentage by mass:

[0101] C: 0.03%~0.05%;

[0102] Si: 3% to 3.5%;

[0103] Mn: 0.08%~0.25%;

[0104] Als: 0.01%~0.03%;

[0105] Cu: 0.3%~0.6%

[0106] N: 0.006%~0.012%;

[0107] Sn: 0.01%~0.04%;

[0108] P: 0~0.03%;

[0109] S: 0~0.015%;

[0110] The rest is iron and other inevitable impurities.

[0111] In some of the above embodiments, the inventors have conducted a large number of experiments and further optimized the mass percentage of each component to adjust the content of inhibitors in the oriented silicon steel, thereby further improving the iron loss and magnetic induction of the oriented silicon steel.

[0112] In some embodiments of the present application, the thickness of the high magnetic induction oriented silicon steel is 0.15-0.3 mm.

[0113] In some of the above embodiments, generally speaking, under the condition of constant material and external magnetic field, eddy current loss is proportional to the square of the plate thickness, that is, as the plate thickness decreases, the eddy current loss decreases sharply, thereby reducing the iron loss of the oriented silicon steel; however, the thinning of the thickness will increase the texture components that are unfavorable to magnetism in the recrystallization texture, reduce the components that are favorable to the texture, and reduce the magnetic induction. Therefore, the thickness of the oriented silicon steel is not easy to be too thin. In some embodiments of the present application, the thickness of the high magnetic induction oriented silicon steel is 0.15-0.3mm.

[0114] In some embodiments of the present application, the core loss P of the high magnetic induction oriented silicon steel is 1.7 / 50 ≤1W / kg.

[0115] In some embodiments of the present application, the magnetic polarization intensity J of the high magnetic induction oriented silicon steel is 800 ≥1.88T.

[0116] By testing the data of the high magnetic induction oriented silicon steel composed of the above components, in some embodiments, the maximum iron loss P of the high magnetic induction oriented silicon steel is 1.7 / 50 No more than 1W / kg, and its magnetic polarization intensity J 800 Greater than 1.88T, which meets the performance requirements of high magnetic induction oriented silicon steel on iron loss and magnetic induction in the national standard GB / T2521.2, indicating that the high magnetic induction oriented silicon steel with the components provided in the present application can be prepared by a medium-temperature slab heating process. It can be seen that compared with the medium-temperature oriented silicon steel in the prior art, the iron loss is smaller and the magnetic induction intensity is higher.

[0117] In a second aspect, the present application provides a method for preparing high magnetic induction oriented silicon steel, comprising the following steps:

[0118] S10 provides slabs;

[0119] S20: heating the slab to obtain a heated slab;

[0120] S30 Descaling, rough rolling and finish rolling the heated slab to obtain a hot rolled steel plate;

[0121] S40: cooling the hot-rolled steel sheet to a coiling temperature, coiling, pickling, primary cold rolling, decarburization annealing, secondary cold rolling, and high-temperature annealing to obtain high magnetic induction oriented silicon steel;

[0122] The cooling specifically includes: cooling the hot-rolled steel plate to 750-850°C at 150-400°C / s, and then cooling to the coiling temperature at 50-100°C / s;

[0123] The high magnetic induction oriented silicon steel is composed of the following components by mass percentage:

[0124] C: 0.025%~0.06%;

[0125] Si: 2.9%~3.7%;

[0126] Mn: 0.08%~0.3%;

[0127] Als: 0.01%~0.035%;

[0128] Cu: 0.1%~0.6%;

[0129] N: 0.006%~0.012%;

[0130] Sn: 0.01%~0.1%;

[0131] P: 0~0.03%;

[0132] S: 0~0.015%;

[0133] The rest is iron and other inevitable impurities.

[0134] The technical solution of the present application is a further improvement on the preparation method of oriented silicon steel, mainly in that an ultra-fast cooling process is used to quickly cool the hot-rolled steel plate obtained by fine rolling, thereby reducing the temperature of the peak precipitation of the two-phase particles, refining the size of the two-phase particles, and making the distribution more uniform and the inhibitory force stronger; at the same time, due to the rapid cooling, the degree of microstructure recovery and recrystallization of the hot-rolled steel plate can be shortened, further reducing iron loss and improving magnetic induction.

[0135] In the technical solution of the present application, except for special limitations in the solution, the main process refers to the preparation method of oriented silicon steel in the prior art, and the specific steps and parameters are not further limited. As an example, step S10 specifically includes: ironmaking, desulfurization, converter steelmaking, and continuous casting to obtain a slab with components that meet the requirements.

[0136] In step S20, the coarse inhibitor grains in the slab are fully dissolved by heat treatment to obtain a heated slab.

[0137] In step S30, the heated slab is descaled, rough rolled and finish rolled. During the rough rolling and finish rolling processes, a large amount of finely dispersed Cu2S will precipitate from the hot-rolled steel plate as the main inhibitor, and a small amount of finely dispersed AlN will also precipitate. At the same time, Sn can be segregated at the interface between the Cu2S, AlN particles and the matrix, inhibiting the coarsening of these inhibitor particles, making them better dispersed, and enhancing the inhibitory effect of the inhibitor in the steel.

[0138] In the technical solution of this application, the most important improvement compared with the prior art is the cooling process of the hot-rolled steel plate. In the prior art, the cooling method for hot-rolled steel plates is generally laminar cooling. Since conventional laminar cooling is not very effective in removing the steam film attached to the surface of the steel plate, the cooling rate of conventional laminar cooling is not very fast. The fastest cooling rate of laminar cooling is also below 100℃ / s. However, the inventors found that at this cooling rate, the two-phase particles formed by the inhibitor in the steel are easy to aggregate and become coarse, such as the attached Figure 2 As shown, the ability to hinder the migration of primary recrystallization grain boundaries is weak, and it is difficult to limit the average size of primary recrystallized grains, which leads to the reduction of magnetic properties of oriented silicon steel.

[0139] In this regard, the inventors used an ultra-fast cooling process to cool the hot-rolled steel plate. The ultra-fast cooling process has the effect of efficiently removing the steam film attached to the surface of the steel plate, so that the cooling rate is much higher than the conventional laminar cooling, and the cooling rate can reach up to 400°C / s. Therefore, the inventors used the ultra-fast cooling process to quickly cool the hot-rolled steel plate that had just finished finishing rolling, cooling it to 750-850°C at 150-400°C / s, so that the hot-rolled steel plate can be quickly reduced from the final rolling temperature to below the peak temperature of inhibitor precipitation, thereby reducing the formation of coarse two-phase particles during the slow cooling process, thereby refining the size of the two-phase particles that serve as inhibitors in oriented silicon steel, such as the attached Figure 1 As shown, the suppression ability is improved, thereby ultimately improving the magnetic induction properties of oriented silicon steel.

[0140] Then, the steel is cooled to the coiling temperature at a rate of 50-100°C / s and then coiled. The steel is then pickled, subjected to primary cold rolling, decarburization annealing, secondary cold rolling and high temperature annealing to obtain high magnetic induction oriented silicon steel.

[0141] It should be noted that the technical solution of this application does not further limit the specific condition parameters of other steps, and those skilled in the art can make corresponding choices based on the existing technology. As an example, in step S40, decarburization annealing specifically includes: decarburization annealing at 800-900°C for 100-200s; high temperature annealing specifically includes: coating MgO on the surface of the steel plate after secondary cold rolling and then high temperature annealing at 1150-1250°C for 10-24h.

[0142] In some embodiments of the present application, step S20 specifically includes:

[0143] The slab is heated at 1280-1320° C. for more than 200 minutes to obtain a heated slab.

[0144] In some of the above embodiments, in order to fully dissolve the coarse inhibitor grains in the slab and better precipitate fine dispersed two-phase grains during the hot rolling process, the slab needs to be heated at 1280-1320°C for more than 200 minutes to fully dissolve the inhibitor.

[0145] In some embodiments of the present application, in the step S30, the final rolling temperature of the finish rolling is 920-1050°C.

[0146] In some of the above embodiments, the final rolling temperature is 920-1050°C in order to prevent the two-phase particles acting as inhibitors in the slab from agglomerating and becoming coarse during the finishing rolling process, thereby reducing the inhibition ability and ultimately leading to a reduction in the magnetic induction performance of the oriented silicon steel. Therefore, the final rolling temperature needs to be controlled at 920-1050°C.

[0147] In some embodiments of the present application, in the step S40, the coiling temperature is 450-620°C.

[0148] In some of the above embodiments, the hot-rolled steel plate is cooled to 750-850°C by an ultra-fast cooling process at 150-400°C / s, and then cooled to 450-620°C by a laminar cooling process at 50-100°C / s. Fine dispersed two-phase grains can be obtained as inhibitors, which can effectively improve the inhibitory effect of the inhibitor, thereby improving the magnetic induction properties of the oriented silicon steel.

[0149] In a third aspect, the present application provides a product manufactured by processing the high magnetic steel oriented silicon steel according to any embodiment of the first aspect or the high magnetic steel oriented silicon steel manufactured by the manufacturing method according to any embodiment of the second aspect.

[0150] The following examples are used to describe in more detail a high magnetic induction oriented silicon steel and a preparation method and product thereof, but the present application is not limited to these examples. It should be noted that in the following specific examples, conditions and parameters not explicitly specified can be determined by those skilled in the art according to the prior art and are not described in detail here.

[0151] The core loss P1.7 / 50 and magnetic polarization intensity J of high magnetic induction oriented silicon steel were measured using GB / T 13789-2008 "Method for measuring magnetic properties of electrical steel sheets (strips) using a single-piece tester" 800 .

[0152] Example 1

[0153] Through ironmaking, desulfurization, converter steelmaking, and continuous casting, slabs with components that meet the requirements are obtained;

[0154] The slab is heated at 1300°C for 300 minutes to obtain a heated slab;

[0155] The heated slab is descaled, rough rolled and finished rolled to obtain a hot rolled steel plate, wherein the final rolling temperature is 955°C;

[0156] The hot-rolled steel plate is first cooled to 795°C at 260°C / s using an ultra-fast cooling process, and then cooled to 560°C at 55°C / s using a laminar cooling process. It is then coiled, pickled, cold rolled once, decarburized annealed, cold rolled twice, and annealed at high temperature to obtain 0.27mm thick high magnetic induction oriented silicon steel.

[0157] The components and mass percentages of the high magnetic induction oriented silicon steel are shown in Table 1.

[0158] Core loss P1.7 / 50 and magnetic polarization intensity J of high magnetic induction oriented silicon steel 800 The test results are shown in Table 2.

[0159] At the same time, the distribution of the two-phase particles in the steel plate obtained by cooling and coiling the hot-rolled steel plate was observed using an electron microscope. The results are as follows Figure 1 .

[0160] Example 2

[0161] Through ironmaking, desulfurization, converter steelmaking, and continuous casting, slabs with components that meet the requirements are obtained;

[0162] The slab is heated at 1301°C for 305min to obtain a heated slab;

[0163] The heated slab is descaled, rough rolled and finished rolled to obtain a hot rolled steel plate, wherein the final rolling temperature is 960°C;

[0164] The hot-rolled steel plate is first cooled to 780°C using an ultra-fast cooling process at 270°C / s, and then cooled to 555°C using a laminar cooling process at 52°C / s. It is then coiled and pickled, cold rolled once, decarburized annealed, cold rolled twice, and annealed at high temperature to obtain 0.27mm thick high magnetic induction oriented silicon steel.

[0165] The components and mass percentages of the high magnetic induction oriented silicon steel are shown in Table 1.

[0166] Core loss P1.7 / 50 and magnetic polarization intensity J of high magnetic induction oriented silicon steel 800 The test results are shown in Table 2.

[0167] Example 3

[0168] Through ironmaking, desulfurization, converter steelmaking, and continuous casting, slabs with components that meet the requirements are obtained;

[0169] The slab is heated at 1305°C for 310 min to obtain a heated slab;

[0170] The heated slab is descaled, rough rolled and finished rolled to obtain a hot rolled steel plate, wherein the final rolling temperature is 950°C;

[0171] The hot-rolled steel plate is cooled to 565°C at 60°C / s by a laminar cooling process, and is coiled, pickled, cold-rolled once, decarburized annealed, cold-rolled twice, and annealed at high temperature to obtain a 0.27mm thick high magnetic induction oriented silicon steel.

[0172] The components and mass percentages of the high magnetic induction oriented silicon steel are shown in Table 1.

[0173] Core loss P1.7 / 50 and magnetic polarization intensity J of high magnetic induction oriented silicon steel 800 The test results are shown in Table 2.

[0174] At the same time, the distribution of the two-phase particles in the steel plate obtained by cooling and coiling the hot-rolled steel plate was observed using an electron microscope. The results are as follows Figure 2 .

[0175] Example 4

[0176] Through ironmaking, desulfurization, converter steelmaking, and continuous casting, slabs with components that meet the requirements are obtained;

[0177] The slab is heated at 1302°C for 307 minutes to obtain a heated slab;

[0178] The heated slab is descaled, rough rolled and finished rolled to obtain a hot rolled steel plate, wherein the final rolling temperature is 965°C;

[0179] The hot-rolled steel plate is cooled to 570°C at 58°C / s by a laminar cooling process, and is coiled, pickled, cold-rolled once, decarburized annealed, cold-rolled twice, and annealed at high temperature to obtain a 0.27mm thick high magnetic induction oriented silicon steel.

[0180] The components and mass percentages of the high magnetic induction oriented silicon steel are shown in Table 1.

[0181] Core loss P1.7 / 50 and magnetic polarization intensity J of high magnetic induction oriented silicon steel 800 The test results are shown in Table 2.

[0182] Example 5

[0183] Through ironmaking, desulfurization, converter steelmaking, and continuous casting, slabs with components that meet the requirements are obtained;

[0184] The slab is heated at 1295°C for 320 minutes to obtain a heated slab;

[0185] The heated slab is descaled, rough rolled and finished rolled to obtain a hot rolled steel plate, wherein the final rolling temperature is 961°C;

[0186] The hot-rolled steel plate is first cooled to 790°C at 265°C / s using an ultra-fast cooling process, and then cooled to 557°C at 53°C / s using a laminar cooling process. It is then coiled, pickled, cold rolled once, decarburized annealed, cold rolled twice, and annealed at high temperature to obtain 0.23mm thick high magnetic induction oriented silicon steel.

[0187] The components and mass percentages of the high magnetic induction oriented silicon steel are shown in Table 1.

[0188] Core loss P1.7 / 50 and magnetic polarization intensity J of high magnetic induction oriented silicon steel 800 The test results are shown in Table 2.

[0189] Example 6

[0190] Through ironmaking, desulfurization, converter steelmaking, and continuous casting, slabs with components that meet the requirements are obtained;

[0191] The slab is heated at 1300°C for 315 minutes to obtain a heated slab;

[0192] The heated slab is descaled, rough rolled and finished rolled to obtain a hot rolled steel plate, wherein the final rolling temperature is 964°C;

[0193] The hot-rolled steel plate is first cooled to 798°C using an ultra-fast cooling process at 262°C / s, and then cooled to 556°C using a laminar cooling process at 52°C / s. It is then coiled and pickled, cold rolled once, decarburized annealed, cold rolled twice, and annealed at high temperature to obtain 0.23mm thick high magnetic induction oriented silicon steel.

[0194] The components and mass percentages of the high magnetic induction oriented silicon steel are shown in Table 1.

[0195] Core loss P1.7 / 50 and magnetic polarization intensity J of high magnetic induction oriented silicon steel 800 The test results are shown in Table 2.

[0196] Example 7

[0197] Through ironmaking, desulfurization, converter steelmaking, and continuous casting, slabs with components that meet the requirements are obtained;

[0198] The slab is heated at 1302°C for 312 minutes to obtain a heated slab;

[0199] The heated slab is descaled, rough rolled and finished rolled to obtain a hot rolled steel plate, wherein the final rolling temperature is 963°C;

[0200] The hot-rolled steel plate is cooled to 559°C at 60°C / s by a laminar cooling process, and is coiled, pickled, cold-rolled once, decarburized annealed, cold-rolled twice, and annealed at high temperature to obtain a 0.23mm thick high magnetic induction oriented silicon steel.

[0201] The components and mass percentages of the high magnetic induction oriented silicon steel are shown in Table 1.

[0202] Core loss P1.7 / 50 and magnetic polarization intensity J of high magnetic induction oriented silicon steel 800 The test results are shown in Table 2.

[0203] Example 8

[0204] Through ironmaking, desulfurization, converter steelmaking, and continuous casting, slabs with components that meet the requirements are obtained;

[0205] The slab is heated at 1300°C for more than 307 minutes to obtain a heated slab;

[0206] The heated slab is descaled, rough rolled and finished rolled to obtain a hot rolled steel plate, wherein the final rolling temperature is 957°C;

[0207] The hot-rolled steel plate is cooled to 550°C at 59°C / s by a laminar cooling process, and is coiled, pickled, cold-rolled once, decarburized annealed, cold-rolled twice, and annealed at high temperature to obtain a 0.23mm thick high magnetic induction oriented silicon steel.

[0208] The components and mass percentages of the high magnetic induction oriented silicon steel are shown in Table 1.

[0209] Core loss P1.7 / 50 and magnetic polarization intensity J of high magnetic induction oriented silicon steel 800 The test results are shown in Table 2.

[0210] Table 1

[0211] C Si Mn Als Cu N Sn P S Example 1 0.040 3.10 0.22 0.0200 0.500 0.0090 0.07 0.012 0.010 Example 2 0.039 3.12 0.20 0.0195 0.505 0.0095 0.03 0.011 0.008 Example 3 0.040 3.10 0.22 0.0200 0.500 0.0090 0.07 0.012 0.010 Example 4 0.039 3.12 0.20 0.0195 0.505 0.0095 0.03 0.011 0.008 Example 5 0.039 3.12 0.20 0.0195 0.505 0.0095 0.03 0.011 0.008 Example 6 0.040 3.10 0.22 0.0200 0.500 0.0090 0.07 0.012 0.010 Example 7 0.040 3.10 0.22 0.0200 0.500 0.0090 0.07 0.012 0.010 Example 8 0.039 3.12 0.20 0.0195 0.505 0.0095 0.03 0.011 0.008

[0212] Note: C represents the mass content of carbon, in %;

[0213] Si represents the mass content of silicon, in %;

[0214] Mn represents the mass content of manganese, in %;

[0215] Als represents the mass content of acid-soluble aluminum, in %;

[0216] Cu represents the mass content of copper, in %;

[0217] N represents the mass content of nitrogen, in %;

[0218] Sn represents the mass content of tin, in %;

[0219] P represents the mass content of phosphorus, in %;

[0220] S represents the mass content of sulfur, in %;

[0221] The rest is iron and inevitable impurities.

[0222] Table 2

[0223] Thickness(mm) P1.7 / 50(W / kg) <![CDATA[J 800 (T)]]> Example 1 0.27 0.98 1.90 Example 2 0.27 0.97 1.91 Example 3 0.27 1.07 1.87 Example 4 0.27 1.08 1.86 Example 5 0.23 0.93 1.91 Example 6 0.23 0.95 1.91 Example 7 0.23 1.05 1.87 Example 8 0.23 1.04 1.87

[0224] From the results in Table 2, it can be seen that each embodiment has lower iron loss and better magnetic induction performance, especially embodiments 1-2 and embodiments 5-6. By optimizing the components and mass percentages of oriented silicon steel and using the cooling process of ultra-fast cooling + layer cooling, high magnetic induction oriented silicon steel with iron loss less than 1W / kg and magnetic polarization intensity greater than 1.88T can be obtained. It meets the requirements of GB / T 2521.2 on the performance of high magnetic induction oriented silicon steel, and since the high magnetic induction oriented silicon steel provided in this application uses Cu2S as the main inhibitor, it can be produced using a medium-temperature slab heating process, thereby effectively reducing production costs and saving resources. Compared with embodiments 1-2 and embodiments 5-6, embodiments 3-4 and embodiments 7-8 have relatively high iron losses and weak magnetic polarization intensity due to the coarse aggregation of the two-phase particles during the cooling process, resulting in poor inhibition effect. As Figure 1 and Figure 2 As shown, Figure 1 is the distribution diagram of the two-phase particles in Example 1, Figure 2 From the distribution diagram of the two-phase particles in Example 3, it can be seen that the two-phase particles obtained by using the ultra-fast cooling + laminar cooling process are more evenly distributed and dispersed than those obtained by using only laminar cooling, and therefore have a better inhibitory effect, so that the final oriented silicon steel has better magnetic polarization strength.

[0225] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for preparing high magnetic induction oriented silicon steel, characterized in that: The following steps are involved: S10 provides slabs; S20: heating the slab at 1280-1320° C. for more than 200 min to obtain a heated slab; S30 Descaling, rough rolling and finish rolling the heated slab to obtain a hot rolled steel plate; S40: cooling the hot-rolled steel sheet to a coiling temperature, coiling, pickling, primary cold rolling, decarburization annealing, secondary cold rolling, and high-temperature annealing to obtain high magnetic induction oriented silicon steel; The cooling specifically includes: cooling the hot-rolled steel plate to 750-850°C at 150-400°C / s, and then cooling to the coiling temperature at 50-100°C / s; The high magnetic induction oriented silicon steel is composed of the following components by mass percentage: C：0.025%~0.06%； Si: 2.9%~3.7%; Mn: 0.08%~0.3%; Als: 0.01%~0.035%; Cu: 0.5%~0.6%; N：0.006%~0.012%； Sn: 0.01%~0.1%; P：0~0.03%； S：0~0.015%； The rest is iron and other inevitable impurities.

2. The preparation method according to claim 1, characterized in that: In terms of mass percentage, it is composed of the following components: C：0.03%~0.05%； Si: 3%~3.5%; Mn: 0.08%~0.25%; Als: 0.01%~0.03%; Cu: 0.5%~0.6%; N：0.006%~0.012%； Sn: 0.01%~0.04%; P：0~0.03%； S：0~0.015%； The rest is iron and other inevitable impurities.

3. The preparation method according to claim 1 or 2, characterized in that: The thickness of the high magnetic induction oriented silicon steel is 0.15-0.3 mm.

4. The preparation method according to claim 3, characterized in that: The core loss P of the high magnetic induction oriented silicon steel 1.7 / 50 ≤1W / kg.

5. The preparation method according to claim 3, characterized in that: The magnetic polarization intensity J of the high magnetic induction oriented silicon steel 800 ≥1.88T.

6. The preparation method according to claim 1, characterized in that: In the step S30, the final rolling temperature of the finish rolling is 920-1050°C.

7. The preparation method according to claim 1, characterized in that: In the step S40, the coiling temperature is 450-620°C.

8. A product, characterized in that It is made by processing the high magnetic induction oriented silicon steel prepared by the preparation method according to any one of claims 1 to 7.

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