Application of Al2O3-13TiO2 composite ceramic powder in preparation of wear-resistant layer on surface of grinding roller

Abstract

The invention provides application of Al2O3-13TiO2 composite ceramic powder in preparation of a wear-resistant layer on the surface of a grinding roller, and belongs to the technical field of industry. The Al2O3-13TiO2 composite ceramic powder is used as a spraying material of the surface of the grinding roller, the wear-resistant layer on the surface of the grinding roller is prepared through a plasma spraying method, the hardness of the wear-resistant layer is improved by 30% compared with that of an existing grinding roller, and the service life is prolonged by 20%.

Description

Technical Field

[0001] The invention belongs to the field of industrial technology, and in particular relates to application of Al2O3-13TiO2 composite ceramic powder in preparing a wear-resistant layer on the surface of a grinding roller. Background Art

[0002] Roller mills are the primary equipment for processing wheat into flour. They operate by grinding wheat grains using two parallel, counter-rotating rollers. Rollers are key components that determine the mill's operational stability, flour yield, and the nutritional content of flour. They are primarily divided into toothed rollers and sandblasted rollers, used in the skin and core grinding systems, respectively. However, during the grinding process, roller surface wear causes changes in the roller's surface geometry. While surface treatment technologies such as carbonitriding, laser quenching, and physical vapor deposition are currently being used to improve the roller's wear resistance, their low hardness and insufficient wear resistance still severely impact flour quality and processing efficiency. Summary of the Invention

[0003] In light of this, the present invention aims to provide an application of an Al2O3-13TiO2 composite ceramic powder for preparing a wear-resistant coating on the surface of a grinding roller. This invention utilizes the Al2O3-13TiO2 composite ceramic powder as a spraying material for the grinding roller surface, using a plasma spraying method to produce a wear-resistant coating on the grinding roller surface. The coating has a hardness that is 30% higher than that of existing grinding rollers, and its service life is increased by 20%.

[0004] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0005] The invention provides an application of Al2O3-13TiO2 composite ceramic powder in preparing a wear-resistant layer on the surface of a grinding roller.

[0006] The present invention provides a method for preparing a wear-resistant layer on the surface of a grinding roller, comprising: spraying Ni-5Al powder on the surface of the grinding roller by a plasma spraying method to obtain a bonding bottom layer; and then spraying Al2O3-13TiO2 composite ceramic powder on the bonding bottom layer to obtain the wear-resistant layer on the surface of the grinding roller.

[0007] Preferably, the preparation method of the grinding roller comprises: polishing the base white cast iron until smooth, then cleaning it with anhydrous ethanol and acetone in sequence, drying it, and sandblasting the sprayed surface with brown corundum to obtain the grinding roller.

[0008] Preferably, the particle size of the brown corundum is 0.52-0.53 mm.

[0009] Preferably, the plasma spraying method of the bonding bottom layer includes: spraying current 500-600A, spraying distance 130-150mm, main gas flow rate 40-50L·min -1, auxiliary gas flow rate is 0.5~1.5L·min -1 .

[0010] Preferably, the plasma spraying method of the bonding bottom layer includes: spraying current 550A, spraying distance 140mm, main gas flow rate 45L·min -1 , auxiliary gas flow rate is 1.0L·min -1 .

[0011] Preferably, the plasma spraying method of the wear-resistant layer on the surface of the grinding roller includes: spraying current 600-700A, spraying distance 80-120mm, main gas flow rate 45-55L·min -1 , auxiliary gas flow rate is 0.5~1.1L·min -1 .

[0012] Preferably, the plasma spraying method of the wear-resistant layer on the surface of the grinding roller includes: spraying current 650A, spraying distance 100mm, main gas flow rate 45L·min -1 , auxiliary gas flow rate is 1.1L·min -1 .

[0013] The present invention also provides a wear-resistant grinding roller prepared by the above preparation method.

[0014] The present invention also provides application of the wear-resistant grinding roller in preparing a roller mill.

[0015] The present invention uses Al2O3-13TiO2 composite ceramic powder as the spraying material on the grinding roller surface and adopts the plasma spraying method to prepare the grinding roller surface wear-resistant layer. Its hardness is increased by 30% compared with the existing grinding roller, and its service life is increased by 20%. The hardness, bonding strength and wear rate of the grinding roller surface wear-resistant layer prepared in the specific embodiment of the present invention are 966.8HV, 23.5MPa and 0.16×10 -4 mm 3 / (N·m). BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Figure 2 is a relationship diagram of coating hardness, bonding strength, wear rate and factor effects, where (a) and (b) are the relationship between coating hardness and factor effects, (c) and (d) are the relationship between coating bonding strength and factor effects, and (e) and (f) are the relationship between coating wear rate and factor effects. DETAILED DESCRIPTION

[0017] The invention provides an application of Al2O3-13TiO2 composite ceramic powder in preparing a wear-resistant layer on the surface of a grinding roller.

[0018] In the present invention, the composite ceramic powder is preferably an Al2O3-xTiO2 composite powder with a TiO2 content of 13%.

[0019] The present invention has no special limitation on the source of the Al2O3-xTiO2 composite powder, and conventional commercial products in the field can be used.

[0020] In the present invention, the particle size of the Al2O3-xTiO2 composite powder is preferably 15 to 45 μm, and the purity is preferably greater than 99.7%.

[0021] The present invention provides a method for preparing a wear-resistant layer on the surface of a grinding roller, comprising: spraying Ni-5Al powder on the surface of the grinding roller by a plasma spraying method to obtain a bonding bottom layer; and then spraying Al2O3-13TiO2 composite ceramic powder on the bonding bottom layer to obtain the wear-resistant layer on the surface of the grinding roller.

[0022] The present invention has no special limitation on the source of the Ni-5Al powder, and conventional commercial products in the art can be used.

[0023] In the present invention, the particle size of the Ni-5Al powder is preferably 15 to 45 μm, and the purity is preferably greater than 99.7%.

[0024] In the present invention, the base white cast iron is preferably polished smooth with sandpaper and cleaned with sufficient anhydrous ethanol and acetone, dried in a drying oven, and then sandblasted with brown corundum with a particle size of 0.526 mm for use.

[0025] In the present invention, Al2O3-xTiO2 composite powder with a TiO2 content of 13% is preferably used as the spraying material, and an Al2O3-13TiO2 (aluminum titanium oxide) coating is prepared on the surface of Φ25mm×10mm KmTBCr12 white cast iron by plasma spraying technology, and then the optimal process parameters for coating preparation are determined by orthogonal experiment and range analysis.

[0026] In the present invention, the plasma equipment is preferably LBP-100.

[0027] The present invention also provides a wear-resistant grinding roller prepared by the above preparation method.

[0028] The present invention also provides application of the wear-resistant grinding roller in preparing a roller mill.

[0029] The technical solutions provided by the present invention are described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0030] Example 1

[0031] First, the base white cast iron was polished smooth with sandpaper and cleaned with sufficient anhydrous ethanol and acetone. After drying in a drying oven, the spraying surface was sandblasted with brown corundum with a particle size of 0.526 mm (millimeter) for standby use.

[0032] Next, a plasma device (LBP-100) was used to spray Ni-5Al powder as the bonding layer, followed by Al2O3-13TiO2 composite ceramic powder. All powders had a particle size range of 15 to 45 μm (micrometers) and a purity greater than 99.7%. The bonding layer process parameters were: spray current 550A (ampere), spray distance 140mm, and main gas flow rate 45L·min -1 (liters per minute), auxiliary gas flow rate is 1.0L min -1 .

[0033] The spraying current (I), spraying distance (H), main gas flow rate (Ar) and auxiliary gas flow rate (H2) were selected as experimental factors, and their factor levels are shown in Table 1. The L9 (3 4 ) Configuration factors and level scheme table, see Table 2.

[0034] The coating hardness was tested by a HV-1000SPTA micro Vickers hardness tester (Laizhou Weiyi Testing Equipment Manufacturing Co., Ltd.), with a load of 9.8N applied and maintained for 10s. Five different positions were selected to obtain the average microhardness. Referring to the national standard GB / T8642-2002 "Thermal Spraying - Determination of Tensile Bond Strength", the coating bonding strength was tested using a DNS200 electronic universal testing machine (Changchun Mechanical Science Research Institute Co., Ltd.). Each sample was tested 5 times and the average value was taken. The coating wear resistance test was carried out on an MDW-02G high-speed reciprocating friction and wear testing machine (Jinan Yihua Tribology Testing Technology Co., Ltd.). The grinding ball material was Si3N4 with a diameter of 6.35mm, the applied load was 15N, the reciprocating frequency was 2Hz, the reciprocating stroke was 20mm, the friction mode was reciprocating dry friction, and the test time was 30min. SPSSAU was used to perform range analysis on the orthogonal experimental data. The depth of the wear scar on the coating surface was measured using a VR-3200 3D profilometer. Origin was used to perform integral calculations to obtain the cross-sectional area of the wear scar. The coating wear rate was then calculated using formulas (1) and (2).

[0035] V=S×l (1)

[0036] W=V / (FL) (2)

[0037] Where V is the wear volume of the coating sample (mm 3 ); S is the cross-sectional area of the wear scar (mm 2 ); l is the wear scar length (mm); W is the wear rate (mm 3 / (N·m)); F is the load applied to the grinding balls (N); L is the total sliding distance (m).

[0038] The hardness, bonding strength and wear rate of the coating are the indicators, and the experimental results are as follows: Figure 1 As shown in the figure, the importance of each factor on the coating quality is determined to be: spray current > spray distance > auxiliary gas flow > main gas flow, that is, the spray current is 650A, the spray distance is 100mm, the Ar flow rate is 45L / min, and the H2 flow rate is 1.1L / min. The hardness, bonding strength, and wear rate of the prepared coating are 966.8HV, 23.5MPa, and 0.16×10 -4 mm 3 / (N·m)

[0039] Table 1 Coating process influencing factors and level numbers

[0040]

[0041] Table 24 Factor 3 level orthogonal experiment table

[0042]

[0043]

[0044] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. Application of Al2O3-13TiO2 composite ceramic powder in preparing wear-resistant layer on grinding roller surface.

2. A method for preparing a wear-resistant layer on the surface of a grinding roller, characterized in that: include: The Ni-5Al powder is sprayed on the surface of the grinding roller by plasma spraying to obtain a bonding bottom layer; then the Al2O3-13TiO2 composite ceramic powder is sprayed on the bonding bottom layer to obtain a wear-resistant layer on the surface of the grinding roller.

3. The method for preparing a wear-resistant layer on the surface of a grinding roller according to claim 2, characterized in that: The preparation method of the grinding roller comprises the following steps: polishing the base white cast iron until smooth, then cleaning it with anhydrous ethanol and acetone in sequence, drying it, and sandblasting the sprayed surface with brown corundum to obtain the grinding roller.

4. The method for preparing a wear-resistant layer on the surface of a grinding roller according to claim 3, characterized in that: The particle size of the brown corundum is 0.52-0.53 mm.

5. The method for preparing a wear-resistant layer on the surface of a grinding roller according to claim 2, wherein: The plasma spraying method of the bonding bottom layer includes: spraying current 500-600A, spraying distance 130-150mm, main gas flow rate 40-50L·min -1 , auxiliary gas flow rate is 0.5~1.5L·min -1 .

6. The method for preparing a wear-resistant layer on the surface of a grinding roller according to claim 5, characterized in that: The plasma spraying method of the bonding bottom layer includes: spraying current 550A, spraying distance 140mm, main gas flow rate 45L·min -1 , auxiliary gas flow rate is 1.0L·min -1 .

7. The method for preparing a wear-resistant layer on the surface of a grinding roller according to claim 2, characterized in that: The plasma spraying method for the wear-resistant layer on the surface of the grinding roller includes: spraying current 600-700A, spraying distance 80-120mm, main gas flow rate 45-55L·min -1 , auxiliary gas flow rate is 0.5~1.1L·min -1 .

8. The method for preparing a wear-resistant layer on the surface of a grinding roller according to claim 2, characterized in that: The plasma spraying method for the wear-resistant layer on the surface of the grinding roller includes: spraying current 650A, spraying distance 100mm, main gas flow rate 45L·min -1 , auxiliary gas flow rate is 1.1L·min -1 .

9. A wear-resistant grinding roller prepared by the method for preparing a wear-resistant layer on the surface of a grinding roller according to any one of claims 2 to 8.

10. Use of the wear-resistant grinding roller according to claim 9 in preparing a roller mill.

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