A method for preparing titanium-containing magnesium oxide for oriented silicon steel

Abstract

The invention relates to the technical field of electrical steel sheets, and proposes a method for preparing titanium-containing magnesium oxide for oriented silicon steel, comprising the following steps: S1, adding magnesium oxide, titanium dioxide and a grinding aid into water, grinding to obtain a grinding slurry; S2, filtering the grinding slurry to obtain a magnesium-titanium filter cake; S3, calcining the magnesium-titanium filter cake to obtain titanium-containing magnesium oxide; the weight proportion of magnesium oxide is 90-100 parts, the weight proportion of titanium dioxide is 5-10 parts, and the weight proportion of water is 900-1000 parts; the grinding aid comprises the following components in weight proportions: 0.1-0.3 parts of poloxamer, 0.1-0.2 parts of sodium p-styrene sulfonate, 0-0.2 parts of polyethylene glycol monolaurate, and 0-0.2 parts of sodium citrate. Through the above technical scheme, the problem that the oriented silicon steel in the prior art needs to physically add titanium dioxide when coating magnesium oxide, thereby resulting in poor magnetic properties of the oriented silicon steel and increased iron loss is solved.

Description

Technical Field

[0001] The invention relates to the technical field of electrical steel sheets, and in particular to a method for preparing titanium-containing magnesium oxide special for oriented silicon steel. Background Art

[0002] Oriented silicon steel is an important soft magnetic ferrosilicon alloy material, mainly used to make the iron core of motors and transformers. In the production process of oriented silicon steel, magnesium oxide needs to be coated on the surface of oriented silicon steel before high-temperature annealing, and the magnesium oxide needs to contain a certain amount of titanium. At present, the existing technology physically adds titanium dioxide in a certain proportion when coating magnesium oxide, which makes the added titanium dioxide and oriented silicon steel unable to fully combine, resulting in poor magnetic properties of oriented silicon steel and increased iron loss.

[0003] As global energy resources become increasingly scarce, energy conservation has become an urgent issue for the manufacturing industry. The market has an increasingly strong demand for improving the magnetic properties of oriented silicon steel and reducing iron loss. Therefore, in order to improve the magnetic properties of oriented silicon steel and reduce iron loss, it is of great practical significance and application value to develop a preparation method for titanium-containing magnesium oxide specifically for oriented silicon steel. Summary of the invention

[0004] The invention provides a method for preparing titanium-containing magnesium oxide specially used for oriented silicon steel, which solves the problem in the related art that titanium dioxide needs to be physically added when magnesium oxide is coated on oriented silicon steel, thereby causing poor magnetic properties of the oriented silicon steel and increased iron loss.

[0005] The technical solution of the present invention is as follows:

[0006] The present invention provides a method for preparing titanium-containing magnesium oxide specially used for oriented silicon steel, comprising the following steps:

[0007] S1, adding magnesium oxide, titanium dioxide and a grinding aid into water, grinding to obtain a grinding slurry;

[0008] S2, filtering the grinding slurry by hydraulic pressure to obtain a magnesium-titanium filter cake;

[0009] S3, the magnesium-titanium filter cake is calcined to obtain titanium-containing magnesium oxide;

[0010] The weight proportion of the magnesium oxide is 90-100 parts, the weight proportion of the titanium dioxide is 5-10 parts, and the weight proportion of the water is 900-1000 parts;

[0011] The grinding aid comprises the following components in parts by weight: 0.1-0.3 parts of poloxamer, 0.1-0.2 parts of sodium p-styrene sulfonate, 0-0.2 parts of polyethylene glycol monolaurate, and 0-0.2 parts of sodium citrate.

[0012] As a further technical solution, in step S1, during the grinding, the temperature is 65-75° C., the pressure is 0.5-1.0 MPa, and the time is 25-30 min.

[0013] As a further technical solution, in step S1, the grinding includes primary grinding and secondary grinding;

[0014] During the primary grinding, the grinding aid includes the following components in parts by weight: 0.1-0.3 parts of poloxamer and 0.1-0.2 parts of sodium p-styrene sulfonate;

[0015] During the secondary grinding, the grinding aid includes the following components in parts by weight: 0.05-0.2 parts of polyethylene glycol monolaurate and 0.05-0.2 parts of sodium citrate.

[0016] By using different grinding aids for two grindings, the titanium-containing magnesium oxide and the oriented silicon steel can be more fully combined, thereby further improving the magnetic properties of the oriented silicon steel and further reducing the iron loss of the oriented silicon steel.

[0017] As a further technical solution, after the primary grinding, filtering is performed to obtain slurry, and the grinding aid and water used in the secondary grinding are added to the slurry, and secondary grinding is performed to obtain grinding slurry.

[0018] As a further technical solution, in step S1, the time of the first grinding is greater than the time of the second grinding.

[0019] When the time of the first grinding is longer than that of the second grinding, it helps to further promote the combination of titanium-containing magnesium oxide and oriented silicon steel, thereby further improving the magnetic properties of the oriented silicon steel and further reducing the iron loss of the oriented silicon steel.

[0020] As a further technical solution, in step S1, the ratio of the time of the first grinding to the time of the second grinding is 4:1.

[0021] When the ratio of the first grinding time to the second grinding time is 4:1, it helps to further promote the combination of titanium-containing magnesium oxide and oriented silicon steel, thereby further improving the magnetic properties of the oriented silicon steel and further reducing the iron loss of the oriented silicon steel.

[0022] As a further technical solution, in step S2, during the filter pressing, the temperature of the grinding slurry is 25-28°C.

[0023] As a further technical solution, in step S3, during the calcination, the temperature is 920-980° C. and the time is 50-60 min.

[0024] As a further technical solution, in step S3, before calcination, the magnesium-titanium filter cake is dried to a water content of <3wt%.

[0025] As a further technical solution, in step S3, the temperature during the drying is ≤180°C.

[0026] As a further technical solution, in step S3, the calcination further includes air cooling and crushing.

[0027] The invention also provides titanium-containing magnesium oxide specially used for oriented silicon steel, which is prepared by the preparation method.

[0028] As a further technical solution, the titanium content of the titanium-containing magnesium oxide is 5wt%~8wt%;

[0029] The particle size of the titanium-containing magnesium oxide is 2.5 μm≤D90≤3.5 μm.

[0030] The present invention also provides a oriented silicon steel, which is obtained by uniformly mixing the titanium-containing magnesium oxide and water, coating the mixture on the surface of the silicon steel, and then drying and annealing.

[0031] As a further technical solution, the mass ratio of the titanium-containing magnesium oxide to water is 9-10:1.

[0032] As a further technical solution, during the coating, the coating amount is 10-12 g / m 2 .

[0033] As a further technical solution, during the annealing, the temperature is 780-800° C. and the time is 1-1.5 min.

[0034] As a further technical solution, according to GB / T 13789-2022, under a magnetic field of 800A / m, the magnetic induction intensity of the oriented silicon steel is 1.903~1.984T.

[0035] As a further technical solution, according to GB / T 13789-2022, when the magnetic induction intensity is 1.7 T and the alternating magnetic field frequency is 50 Hz, the iron loss of the oriented silicon steel is 0.931-0.992 W / kg.

[0036] The working principle and beneficial effects of the present invention are:

[0037] 1. In the present invention, magnesium oxide and titanium dioxide are ground by adding a grinding aid to prepare titanium-containing magnesium oxide. Titanium-containing magnesium oxide avoids the defect that titanium dioxide and oriented silicon steel cannot be fully combined due to the need to physically add titanium dioxide when magnesium oxide is coated on oriented silicon steel, thereby improving the magnetic properties of oriented silicon steel and reducing the iron loss of oriented silicon steel. DETAILED DESCRIPTION

[0038] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] In the following examples and comparative examples, unless otherwise specified, the purity of magnesium oxide is 99.9wt%, the purity of titanium dioxide is 98.5wt%, the poloxamer is poloxamer 407, the purity of sodium p-styrene sulfonate is 99wt%, the CAS number of polyethylene glycol monolaurate is 9004-81-3, and the purity of sodium citrate is 99wt%.

[0040] Example 1

[0041] A method for preparing titanium-containing magnesium oxide for oriented silicon steel comprises the following steps:

[0042] S1. By weight, 90 parts of magnesium oxide, 5 parts of titanium dioxide, 0.1 parts of poloxamer and 0.1 parts of sodium p-styrene sulfonate were added to 900 parts of water, and ground at 65° C. and 0.8 MPa pressure for 30 min to obtain a grinding slurry;

[0043] S2, cooling the grinding slurry to 25°C, and then filtering it through a plate and frame filter press to obtain a magnesium-titanium filter cake;

[0044] S3. The magnesium-titanium filter cake is calcined at 920° C. for 60 min to obtain titanium-containing magnesium oxide.

[0045] Example 2

[0046] A method for preparing titanium-containing magnesium oxide for oriented silicon steel comprises the following steps:

[0047] S1. By weight, 100 parts of magnesium oxide, 10 parts of titanium dioxide, 0.3 parts of poloxamer and 0.2 parts of sodium p-styrene sulfonate were added to 1000 parts of water, and ground at 75° C. and 0.8 MPa pressure for 25 min to obtain a grinding slurry;

[0048] S2, cooling the grinding slurry to 28°C, and then filtering it through a plate and frame filter press to obtain a magnesium-titanium filter cake;

[0049] S3. Dry the magnesium-titanium filter cake at 180° C. to a water content of 2.5 wt %, calcine at 980° C. for 50 min, and obtain titanium-containing magnesium oxide after air cooling and crushing.

[0050] Example 3

[0051] A method for preparing titanium-containing magnesium oxide for oriented silicon steel comprises the following steps:

[0052] S1. By weight, 100 parts of magnesium oxide, 10 parts of titanium dioxide, 0.3 parts of poloxamer, 0.2 parts of sodium p-styrene sulfonate and 0.1 parts of polyethylene glycol monolaurate were added to 1000 parts of water, and ground at 75° C. and 0.8 MPa pressure for 25 min to obtain a grinding slurry;

[0053] S2, cooling the grinding slurry to 28°C, and then filtering it through a plate and frame filter press to obtain a magnesium-titanium filter cake;

[0054] S3. Dry the magnesium-titanium filter cake at 180° C. to a water content of 2.5 wt %, calcine at 980° C. for 50 min, and obtain titanium-containing magnesium oxide after air cooling and crushing.

[0055] Example 4

[0056] A method for preparing titanium-containing magnesium oxide for oriented silicon steel comprises the following steps:

[0057] S1. By weight, 100 parts of magnesium oxide, 10 parts of titanium dioxide, 0.3 parts of poloxamer, 0.2 parts of sodium p-styrene sulfonate and 0.1 parts of sodium citrate were added to 1000 parts of water, and ground at 75° C. and 0.8 MPa pressure for 25 min to obtain a grinding slurry;

[0058] S2, cooling the grinding slurry to 28°C, and then filtering it through a plate and frame filter press to obtain a magnesium-titanium filter cake;

[0059] S3. Dry the magnesium-titanium filter cake at 180° C. to a water content of 2.5 wt %, calcine at 980° C. for 50 min, and obtain titanium-containing magnesium oxide after air cooling and crushing.

[0060] Example 5

[0061] A method for preparing titanium-containing magnesium oxide for oriented silicon steel comprises the following steps:

[0062] S1. By weight, 100 parts of magnesium oxide, 10 parts of titanium dioxide, 0.3 parts of poloxamer, 0.2 parts of sodium p-styrene sulfonate, 0.05 parts of polyethylene glycol monolaurate and 0.05 parts of sodium citrate were added to 1000 parts of water, and ground at 75° C. and 0.8 MPa pressure for 25 min to obtain a grinding slurry;

[0063] S2, cooling the grinding slurry to 28°C, and then filtering it through a plate and frame filter press to obtain a magnesium-titanium filter cake;

[0064] S3. Dry the magnesium-titanium filter cake at 180° C. to a water content of 2.5 wt %, calcine at 980° C. for 50 min, and obtain titanium-containing magnesium oxide after air cooling and crushing.

[0065] Example 6

[0066] A method for preparing titanium-containing magnesium oxide for oriented silicon steel comprises the following steps:

[0067] S1. By weight, 100 parts of magnesium oxide, 10 parts of titanium dioxide, 0.3 parts of poloxamer and 0.2 parts of sodium p-styrene sulfonate were added to 1000 parts of water, and the mixture was ground at 75°C and 0.8 MPa for 12.5 min, and then filtered to obtain a slurry. 0.05 parts of polyethylene glycol monolaurate, 0.05 parts of sodium citrate and 1000 parts of water were added to the slurry, and the mixture was ground at 75°C and 0.8 MPa for 12.5 min to obtain a grinding slurry.

[0068] S2, cooling the grinding slurry to 28°C, and then filtering it through a plate and frame filter press to obtain a magnesium-titanium filter cake;

[0069] S3. Dry the magnesium-titanium filter cake at 180° C. to a water content of 2.5 wt %, calcine at 980° C. for 50 min, and obtain titanium-containing magnesium oxide after air cooling and crushing.

[0070] Example 7

[0071] A method for preparing titanium-containing magnesium oxide for oriented silicon steel comprises the following steps:

[0072] S1. By weight, 100 parts of magnesium oxide, 10 parts of titanium dioxide, 0.3 parts of poloxamer and 0.2 parts of sodium p-styrene sulfonate were added to 1000 parts of water, and the mixture was ground at 75° C. and 0.8 MPa for 10 min, and then filtered to obtain a slurry. 0.05 parts of polyethylene glycol monolaurate, 0.05 parts of sodium citrate and 1000 parts of water were added to the slurry, and the mixture was ground at 75° C. and 0.8 MPa for 15 min to obtain a grinding slurry.

[0073] S2, cooling the grinding slurry to 28°C, and then filtering it through a plate and frame filter press to obtain a magnesium-titanium filter cake;

[0074] S3. Dry the magnesium-titanium filter cake at 180° C. to a water content of 2.5 wt %, calcine at 980° C. for 50 min, and obtain titanium-containing magnesium oxide after air cooling and crushing.

[0075] Example 8

[0076] A method for preparing titanium-containing magnesium oxide for oriented silicon steel comprises the following steps:

[0077] S1. By weight, 100 parts of magnesium oxide, 10 parts of titanium dioxide, 0.3 parts of poloxamer and 0.2 parts of sodium p-styrene sulfonate were added to 1000 parts of water, and the mixture was ground at 75° C. and 0.8 MPa for 15 min, and then filtered to obtain a slurry. 0.05 parts of polyethylene glycol monolaurate, 0.05 parts of sodium citrate and 1000 parts of water were added to the slurry, and the mixture was ground at 75° C. and 0.8 MPa for 10 min to obtain a grinding slurry.

[0078] S2, cooling the grinding slurry to 28°C, and then filtering it through a plate and frame filter press to obtain a magnesium-titanium filter cake;

[0079] S3. Dry the magnesium-titanium filter cake at 180° C. to a water content of 2.5 wt %, calcine at 980° C. for 50 min, and obtain titanium-containing magnesium oxide after air cooling and crushing.

[0080] Example 9

[0081] A method for preparing titanium-containing magnesium oxide for oriented silicon steel comprises the following steps:

[0082] S1. By weight, 100 parts of magnesium oxide, 10 parts of titanium dioxide, 0.3 parts of poloxamer and 0.2 parts of sodium p-styrene sulfonate were added to 1000 parts of water, and the mixture was ground at 75° C. and 0.8 MPa for 20 min, and then filtered to obtain a slurry. 0.05 parts of polyethylene glycol monolaurate, 0.05 parts of sodium citrate and 1000 parts of water were added to the slurry, and the mixture was ground at 75° C. and 0.8 MPa for 5 min to obtain a grinding slurry.

[0083] S2, cooling the grinding slurry to 28°C, and then filtering it through a plate and frame filter press to obtain a magnesium-titanium filter cake;

[0084] S3. Dry the magnesium-titanium filter cake at 180° C. to a water content of 2.5 wt %, calcine at 980° C. for 50 min, and obtain titanium-containing magnesium oxide after air cooling and crushing.

[0085] Example 10

[0086] A method for preparing titanium-containing magnesium oxide for oriented silicon steel comprises the following steps:

[0087] S1. By weight, 100 parts of magnesium oxide, 10 parts of titanium dioxide, 0.3 parts of poloxamer and 0.2 parts of sodium p-styrene sulfonate were added to 1000 parts of water, and the mixture was ground at 75° C. and 0.8 MPa for 20 min, and then filtered to obtain a slurry. 0.2 parts of polyethylene glycol monolaurate, 0.2 parts of sodium citrate and 1000 parts of water were added to the slurry, and the mixture was ground at 75° C. and 0.8 MPa for 5 min to obtain a grinding slurry.

[0088] S2, cooling the grinding slurry to 28°C, and then filtering it through a plate and frame filter press to obtain a magnesium-titanium filter cake;

[0089] S3. Dry the magnesium-titanium filter cake at 180° C. to a water content of 2.5 wt %, calcine at 980° C. for 50 min, and obtain titanium-containing magnesium oxide after air cooling and crushing.

[0090] Comparative Example 1

[0091] The difference between this comparative example and Example 1 is that, in this comparative example, in step S1, poloxamer is not added, and the weight portion of sodium p-styrene sulfonate added is 0.2 parts.

[0092] Comparative Example 2

[0093] The difference between this comparative example and Example 1 is that, in this comparative example, in step S1, no sodium p-styrene sulfonate is added, and the weight portion of poloxamer added is 0.2 parts.

[0094] Comparative Example 3

[0095] The difference between this comparative example and Example 1 is that, in this comparative example, in step S1, sodium p-styrene sulfonate and poloxamer are not added.

[0096] The titanium content of the titanium-containing magnesium oxide prepared in Examples 1 to 10 was detected by a full-element spectrometer (model XAD-200), and the results showed that the titanium content of the titanium-containing magnesium oxide prepared in Examples 1 to 10 was 5wt% to 8wt%. The particle size of the titanium-containing magnesium oxide prepared in Examples 1 to 10 was detected by a fully automatic laser particle size analyzer (model NKT6100), and the results showed that the particle size of the titanium-containing magnesium oxide prepared in Examples 1 to 10 was 2.5μm≤D90≤3.5μm.

[0097] The titanium-containing magnesium oxide prepared in Examples 1 to 10 and Comparative Examples 1 to 3 was mixed with water at a mass ratio of 9:1, stirred evenly, and heated to 10 g / m 2 The coating amount was respectively coated on the surface of oriented silicon steel (oriented silicon steel consists of the following components in weight percentage: C 0.007%, Si 3.5%, Mn 0.006%, Al 0.03%, N 0.0075%, and the rest is Fe and unavoidable impurities), dried, and annealed at 800℃ for 1min, and then the following performance tests were carried out:

[0098] ① Magnetic induction intensity: Measure the magnetic induction intensity under 800A / m magnetic field in accordance with GB / T 13789-2022 "Method for measuring the magnetic properties of electrical steel strip (sheet) using a single-piece tester";

[0099] ② Iron loss: The iron loss is measured in a 50Hz alternating magnetic field with a magnetic induction intensity of 1.7T in accordance with GB / T 13789-2022 "Method for measuring the magnetic properties of electrical steel strip (sheet) using a single-piece tester".

[0100] The test results are shown in Table 1 below.

[0101] Table 1 Performance test results

[0102]

[0103] The comparison between Example 1 and Comparative Examples 1 to 3 shows that when preparing titanium-containing magnesium oxide, the magnetic properties of oriented silicon steel can be significantly improved and the iron loss can be significantly reduced by the compounding of poloxamer and sodium p-styrene sulfonate. The comparison between Example 5 and Example 2 to 4 shows that the magnetic properties of oriented silicon steel can be further improved and the iron loss can be further reduced by the combination of poloxamer, sodium p-styrene sulfonate, polyethylene glycol monolaurate and sodium citrate. The comparison between Example 5 and Example 6 to 9 shows that the two grinding processes can help to further improve the magnetic properties of oriented silicon steel and further reduce the iron loss of oriented silicon steel. The comparison between Example 8 and Example 6 to 7 shows that when the time of the first grinding is greater than the time of the second grinding, it helps to further improve the magnetic properties of the oriented silicon steel and further reduce the iron loss of the oriented silicon steel. The comparison between Example 8 and Example 9 shows that when the ratio of the time of the first grinding to the time of the second grinding is 4:1, the magnetic properties of the oriented silicon steel can be further improved and the iron loss of the oriented silicon steel can be further reduced.

[0104] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing titanium-containing magnesium oxide for oriented silicon steel, characterized in that: The following steps are involved: S1, adding magnesium oxide, titanium dioxide and a grinding aid into water, grinding to obtain a grinding slurry; S2, filtering the grinding slurry by hydraulic pressure to obtain a magnesium-titanium filter cake; S3, the magnesium-titanium filter cake is calcined to obtain titanium-containing magnesium oxide; The weight proportion of the magnesium oxide is 90-100 parts, the weight proportion of the titanium dioxide is 5-10 parts, and the weight proportion of the water is 900-1000 parts; The grinding aid comprises the following components in parts by weight: 0.1-0.3 parts of poloxamer, 0.1-0.2 parts of sodium p-styrene sulfonate, 0-0.2 parts of polyethylene glycol monolaurate, and 0-0.2 parts of sodium citrate; The titanium content of the titanium-containing magnesium oxide is 5wt% to 8wt%; In step S1, the grinding includes primary grinding and secondary grinding; During the primary grinding, the grinding aid includes the following components in parts by weight: 0.1-0.3 parts of poloxamer and 0.1-0.2 parts of sodium p-styrene sulfonate; During the secondary grinding, the grinding aid includes the following components in parts by weight: 0.05-0.2 parts of polyethylene glycol monolaurate and 0.05-0.2 parts of sodium citrate; In step S1, the time of the first grinding is greater than the time of the second grinding.

2. The method for preparing titanium-containing magnesium oxide for oriented silicon steel according to claim 1, characterized in that: In step S1, during the grinding, the temperature is 65-75° C., the pressure is 0.5-1.0 MPa, and the time is 25-30 min.

3. The method for preparing titanium-containing magnesium oxide for oriented silicon steel according to claim 1, characterized in that: In step S1, the ratio of the first grinding time to the second grinding time is 4:

1.

4. A titanium-containing magnesium oxide specially used for oriented silicon steel, characterized in that: The method is prepared according to any one of claims 1 to 3.

5. The titanium-containing magnesium oxide for oriented silicon steel according to claim 4, characterized in that: The titanium content of the titanium-containing magnesium oxide is 5wt% to 8wt%; The particle size of the titanium-containing magnesium oxide is 2.5 μm≤D90≤3.5 μm.

6. A oriented silicon steel, characterized in that: The titanium-containing magnesium oxide according to claim 4 is uniformly mixed with water, coated on the surface of silicon steel, and then dried and annealed to obtain the product.

7. The oriented silicon steel according to claim 6, characterized in that: According to GB / T 13789-2022, under a magnetic field of 800A / m, the magnetic induction intensity of the oriented silicon steel is 1.903-1.984T.

8. The oriented silicon steel according to claim 6, characterized in that: According to GB / T 13789-2022, when the magnetic induction intensity is 1.7 T and the alternating magnetic field frequency is 50 Hz, the iron loss of the oriented silicon steel is 0.931-0.992 W / kg.

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