A coating for casting and a method of preparation

Abstract

The application provides a casting material and a preparation method, which comprises 5-8% of Al(HCO3)3 powder, 19-22% of a water-based modified polybutadiene resin, 22-27% of an Al(HCO3)3 modified bentonite composite material, 18-23% of water, 10-13% of a MnO2 and bentonite containing (CTAB)3PW12O40 modified ZnO-based composite, and 20-26% of Al2[Si4O10](OH)2 powder. The application has good high-temperature-resistant and non-cracking characteristics, thereby ensuring the surface quality and size stability of the casting.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of inorganic materials, and particularly relates to a casting coating and a preparation method. BACKGROUND

[0002] Chinese patent CN201610488802.0 relates to a casting coating, which comprises a casting upper mold coating and a lower mold coating. The upper mold coating comprises the following substances in parts by weight: amino-modified silicone oil 20-30 parts, epoxy carbon fiber resin 15-25 parts, alumina fiber 30-50 parts, polyhexatitanic acid potassium 20-40 parts, EVA resin 15-27 parts, amino resin 5-7 parts, and ethanol 30-50 parts. The lower mold coating comprises the following substances in parts by weight: magnesium salt whisker 15-25 parts, titanium dioxide 10-16 parts, silica sol 18-26 parts, aluminum oxide 11-7 parts, sodium carboxymethyl cellulose 5-9 parts, and silicon dioxide 20-30 parts. The casting coating effectively solves the problem of poor surface quality of alloy profile castings. However, the size precision of the castings is not high enough. SUMMARY

[0003] The present application mainly provides a casting coating and a preparation method to solve the technical problems in the background art.

[0004] The technical solution adopted by the present application to solve the above technical problems is as follows:

[0005] A casting coating comprises:

[0006] 5-8% of Al(HCO3)3 powder, 19-22% of water-based modified polybutadiene resin, 22-27% of Al(HCO3)3 modified bentonite composite material, 18-23% of water, 20-26% of MnO2 and bentonite-containing (CTAB)3PW 12 O 40 10-13% of modified ZnO-based composite, and 20-26% of Al2[Si4O 10 ](OH)2 powder.

[0007] According to the technical solution of the above casting coating, a preparation method of the casting coating is also provided, which comprises the following steps:

[0008] 5-8% of Al(HCO3)3 powder, 19-22% of water-based modified polybutadiene resin, 22-27% of Al(HCO3)3 modified bentonite composite material, 18-23% of water, 20-26% of MnO2 and bentonite-containing (CTAB)3PW 12 O 40 10-13% of modified ZnO-based composite, 20-26% of Al2[Si4O 10Mix 20-26% of (OH)2 powder and stir evenly in a container to form a casting coating.

[0009] Furthermore, the MnO2 and (CTAB)3PW containing bentonite... 12 O 40 The preparation of modified ZnO-based complexes includes the following steps:

[0010] Step 1: Take the amount of bentonite to be added as (CTAB) 3PW 12 O 40 Take 3-9% by weight of zinc salt ZnSO4 and prepare an aqueous solution containing 50-60 g / L of ZnSO4. Then add twice the molar amount of NaOH of ZnSO4 and stir the solution for 2-5 minutes to obtain a mixed solution.

[0011] Step 2: Add MnO2 powder and (CTAB)3PW containing bentonite to the mixture obtained in Step 1. 12 O 40 Powder, then continue stirring for 0.5-1 hour, and then wash the precipitate 2-3 times with distilled water and anhydrous ethanol respectively;

[0012] Step 3: Place the precipitate washed in Step 2 into a drying oven and dry for 0.5-1 hour, then calcine at 400-500℃ for 2-4 hours to obtain MnO2 and (CTAB)3PW containing bentonite. 12 O 40 Modified ZnO-based composite powder.

[0013] Furthermore, the MnO2 and (CTAB)3PW containing bentonite... 12 O 40 The amount of powder added is 4-9% of the weight of ZnO, and MnO2 and (CTAB)3PW containing bentonite are added. 12 O 40 The weight ratio of the powder is 1:1.1-1.3.

[0014] Furthermore, the preparation of the MnO2 powder includes the following steps:

[0015] Step 1: Weigh 3.5g MnSO4·H2O, 2.6g (NH4)2SO4, and 9.5g (NH4)2S2O8 respectively, dissolve them in 400mL of deionized water, and stir with a stirrer until there is no precipitate or impurities in the solution to obtain a mixed solution;

[0016] Step 2: Transfer the mixture to a 1000mL reaction vessel, place the reaction vessel at 140℃ for 10 hours, and then allow it to cool naturally to room temperature to obtain the precipitate;

[0017] Step three, the obtained precipitate in the reaction kettle is filtered and washed several times and dried to obtain MnO2 powder.

[0018] Further, the bentonite-containing (CTAB)3PW 12 O 40 The preparation of the powder comprises the following steps:

[0019] Step one, 0.5 mol of CTAB is added in 1000 ml of ethanol and 1000 ml of water, and stirred for 15 min, then 0.5 mol of CTAB is added, stirred for 15 min, and then 0.165 mol of phosphotungstic acid is added, stirred for 3-5 min to obtain a mixed solution;

[0020] Step two, the bentonite powder obtained in step two is added to the mixed solution, and stirring is continued for 1 h, and then it is placed at 50°C for 30 min, washed with ethanol, filtered, and dried at 50°C to obtain a bentonite-containing (CTAB)3PW 12 O 40 powder.

[0021] Further, the preparation of the Al(HCO3)3 modified bentonite composite material comprises the following steps:

[0022] Step one, Al(HCO3)3 and bentonite are mixed in a ratio of 3:100, the bentonite is ground to 80-120 mesh, and then Al(HCO3)3 is added in a certain solid-liquid weight ratio of 2:5-8, and stirred to obtain a mixed solution;

[0023] Step two, 2.3-2.7% of Al2[Si4O 10 ](OH)2 powder based on the weight of the Al(HCO3)3 and bentonite mixture is added to the mixed solution obtained in step one, and then stirred for 25-30 min, and then incubated at 75-105°C for 13-15 h, and then filtered and dried to obtain an Al(HCO3)3 modified bentonite composite material.

[0024] Further, in step two, the composite material is ground to 200-325 mesh, and the Al(HCO3)3 modified bentonite composite material, Al(HCO3)3, MnO2, and bentonite-containing (CTAB)3PW 12 O 40 modified ZnO-based composite, and Al2[Si4O 10 ](OH)2 powder have a particle size of 200-325 mesh.

[0025] Further, a first motor is connected to the top end of the stirrer, an output shaft of the first motor is connected to a stirring shaft, and a plurality of stirring blades are installed on the outer surface of the stirring shaft from top to bottom.

[0026] The inside of the blender is provided with a filter screen, which is in sliding connection with the inner wall of the blender and the outer surface of the stirring shaft, and the filter screen is connected with a shaking mechanism.

[0027] Further, the shaking mechanism comprises a plurality of lifting rods installed on the upper surface of the filter screen, a cam abutting against one end of the lifting rods extending to the outside, and a second motor connected with the cam, which is installed on the upper surface of the blender.

[0028] Compared with the prior art, the blender has the beneficial effects that:

[0029] The Al(HCO3)3, Al(HCO3)3 modified bentonite composite material, MnO2 and (CTAB)3PW 12 O 40 modified ZnO-based composite, Al2[Si4O 10 ](OH)2, thereby having good high-temperature-resistant non-cracking characteristics, thus ensuring the surface quality of the castings and the dimensional stability. Al(HCO3)3, Al(HCO3)3 modified bentonite composite material, MnO2 and (CTAB)3PW 12 O 40 modified ZnO-based composite, Al2[Si4O 10 ](OH)2 has bulk strength, prevents caking, has good dispersibility and improves the peelability from the body of the castings. The binder is mainly Al(HCO3)3 modified bentonite composite material, and is simultaneously matched with a water-based modified polybutadiene resin to improve the leveling property, brushing property and improve the bonding strength. The suspending agent is MnO2 and (CTAB)3PW 12 O 40 modified ZnO-based composite.

[0030] The application will be explained in detail below in combination with the drawings and specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0031] Fig. 1 It is a structural schematic view of the blender of the application;

[0032] Fig. 2 It is a sectional view of the blender of the application.

[0033] In the drawings: 10, blender; 11, first motor; 12, stirring shaft; 13, stirring blade; 14, filter screen; 15, shaking mechanism; 151, lifting rod; 152, cam; 153, second motor. DETAILED DESCRIPTION

[0034] For the purpose of promoting an understanding of the application, the application will now be described in greater detail with reference to the figures illustrative embodiments thereof, it is expressly understood that the application can be practiced by variations of the embodiments described herein without departing from the spirit or scope of the present application.

[0035] It is to be understood that where an element such as a layer, region or substrate is referred to as being "on" or "connected to" another element, it can be directly on or connected to the other element or intervening elements can be present. As used herein, the term and the like are intended to mean for the purpose of illustration and description only and are not intended to be limiting of the scope of the present application. In addition, it is to be understood that the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise.

[0036] As used herein, including the claims, the singular form of "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. All technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs unless clearly indicated otherwise. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. All publications, patent applications, patents and other references mentioned herein are incorporated by reference in their entirety.

[0037] Embodiments, please refer to the attached Figs. 1-2 A foundry coating comprising:

[0038] Al(HCO3)3 powder 5-8%, waterborne modified polybutadiene resin 19-22%, Al(HCO3)3 modified bentonite composite 22-27%, water 18-23%, MnO2 and bentonite containing (CTAB)3PW 12 O 40 Modified ZnO based composite 10-13%, Al2[Si4O 10 ](OH)2 powder 20-26%.

[0039] Embodiments, please refer to the attached Figs. 1-2 According to the above embodiments will also provide a method for preparing a foundry coating, comprising the following steps:

[0040] In weight percent Al(HCO3)3 powder 5-8%, waterborne modified polybutadiene resin 19-22%, Al(HCO3)3 modified bentonite composite 22-27%, water 18-23%, MnO2 and bentonite containing (CTAB)3PW 12 O 40 Modified ZnO based composite 10-13%, Al2[Si4O 10 ](OH)2 powder 20-26% are mixed, stirred evenly in the container to form a foundry coating.

[0041] Further, the MnO2 and bentonite-containing (CTAB)3PW 12 O 40 The preparation of the modified ZnO-based composite includes the following steps:

[0042] Step one, take the bentonite addition amount of (CTAB)3PW 12 O 40 3-9% of the weight of ZnSO4, prepare a ZnSO4-containing aqueous solution with a concentration of 50-60 g / L, then add 2 times the molar amount of NaOH to the solution, and stir the solution with a stirrer for 2-5 minutes to obtain a mixed solution;

[0043] Step two, add MnO2 powder and bentonite-containing (CTAB)3PW 12 O 40 powder to the mixed solution obtained in step one, and continue stirring for 0.5-1 h, and then wash the precipitate with distilled water and anhydrous ethanol for 2-3 times;

[0044] Step three, dry the precipitate washed in step two in a drying oven for 0.5-1 h, and then calcine it at 400-500℃ for 2-4 h to obtain the MnO2 and bentonite-containing (CTAB)3PW 12 O 40 modified ZnO-based composite powder.

[0045] Further, the MnO2 and bentonite-containing (CTAB)3PW 12 O 40 The addition amount of the powder is 4-9% of the weight of ZnO, and the weight ratio of MnO2 to bentonite-containing (CTAB)3PW 12 O 40 powder is 1:1.1-1.3.

[0046] Further, the preparation of the MnO2 powder includes the following steps:

[0047] Step one, respectively take 3.5 g of MnSO4·H2O, 2.6 g of (NH4)2SO4, and 9.5 g of (NH4)2S2O8, dissolve them in 400 mL of deionized water, and stir the solution with a stirrer for 10 minutes until no precipitate and no impurities exist in the solution to obtain a mixed solution;

[0048] Step two, transfer the mixed solution to a 1000 mL reaction kettle, place the reaction kettle in an environment at 140℃ for 10 h, and then naturally cool it to room temperature to obtain a precipitate;

[0049] Step three, filter and wash the precipitate obtained in the reaction kettle multiple times, and then dry it to obtain MnO2 powder.

[0050] Further, the bentonite-containing (CTAB)3PW 12 O 40 The powder preparation comprises the following steps:

[0051] Step one, add 0.5 mol of CTAB in 1000 ml of ethanol and 1000 ml of water, stir for 10 min, then add 0.5 mol of CTAB, stir for 15 min, continue to add 0.165 mol of phosphotungstic acid, and react for 3-5 min under stirring condition to obtain a mixed solution;

[0052] Step two, put the bentonite powder into the mixed solution obtained in step two, continue to stir for 1 h, stand for 30 min at 50°C, wash with ethanol, perform suction filtration, and dry at 50°C to obtain the bentonite-containing (CTAB)3PW 12 O 40 powder.

[0053] Further, the preparation of the Al(HCO3)3 modified bentonite composite material comprises the following steps:

[0054] Step one, according to the ratio of Al(HCO3)3 to bentonite of 3:100, grind the bentonite to 80-120 mesh, mix with Al(HCO3)3, and then add water according to a certain solid-liquid weight ratio of 2:5-8, stir uniformly in a stirrer 10 to obtain a mixed solution;

[0055] Step two, add 2.3-2.7% of Al2[Si4O 10 ](OH)2 powder to the mixed solution obtained in step one, then stir for 25-30 min, and after heat preservation at 75-105°C for 13-15 h, filter and dry to obtain the Al(HCO3)3 modified bentonite composite material.

[0056] Further, in step two, the composite material is ground to 200-325 mesh, and the particle size of the Al(HCO3)3 modified bentonite composite material, Al(HCO3)3, MnO2 and the bentonite-containing (CTAB)3PW 12 O 40 modified ZnO-based composite, and Al2[Si4O 10 ](OH)2 powder is 200-325 mesh.

[0057] Further, the top end of the stirrer 10 is connected with a first motor 11, the output shaft of the first motor 11 is connected with a stirring shaft 12, and a plurality of stirring blades 13 are installed on the outer surface of the stirring shaft 12 from top to bottom.

[0058] The inside of the blender 10 is provided with a filter screen 14 which is in sliding connection with the inner wall of the blender 10 and the outer surface of the stirring shaft 12, and the filter screen 14 is connected with a shaking mechanism 15. In this embodiment, the first motor 11 drives the stirring shaft 12 connected with the output shaft of the first motor 11, and the stirring blade 13 on the shaft body is driven by the stirring shaft 12, so as to stir the raw materials in the blender 10 by the stirring blade 13.

[0059] Further, the shaking mechanism 15 includes a plurality of lifting rods 151 installed on the upper surface of the filter screen 14, a cam 152 abutting against one end of the lifting rod 151 extending to the outside, and a second motor 153 connected with the cam 152, wherein the second motor 153 is installed on the upper surface of the blender 10. In this embodiment, the output shaft of the second motor 153 drives the cam 152, the lifting rod 151 is pushed by the cam 152, and the filter screen 14 connected with the rod body is driven by the lifting rod 151 to shake, so that when the stirring blade 13 hits the raw materials, the filter screen 14 is shaken to further guide the raw materials to fall uniformly.

[0060] Embodiment 2

[0061] Different from embodiment 1, each raw material is weighed according to the data of embodiment 2 in table 1.

[0062] Embodiment 3

[0063] Different from embodiment 1, each raw material is weighed according to the data of embodiment 3 in table 1.

[0064] Embodiment 4

[0065] Different from embodiment 1, each raw material is weighed according to the data of embodiment 4 in table 1.

[0066] Embodiment 5

[0067] Different from embodiment 1, each raw material is weighed according to the data of embodiment 5 in table 1.

[0068] Table 1

[0069]

[0070]

[0071]

[0072] The application is described above by way of example with reference to the accompanying drawings, and it is obvious that the specific implementation of the application is not limited to the above-described manner, and as long as such non-essential improvements are made by adopting the method concept and technical solutions of the application, or the concept and technical solutions of the application are directly applied to other occasions without improvement, they are all within the protection scope of the application.

Claims

1. A casting coating, characterized by Comprising: Al(HCO3)3 powder 5-8%, aqueous modified polybutadiene resin 19-22%, Al(HCO3)3 modified bentonite composite 22-27%, water 18-23%, MnO2 and (CTAB)3PW with bentonite 12 O 40 Modified ZnO based composite 10-13%, Al2[Si4O 10 ](OH)2 powder 20-26%.

2. A method for preparing a coating for casting for preparing a coating for casting according to claim 1, characterized in that Comprising the following steps: Formulated with 5-8% by weight of Al(HCO3)3 powder, 19-22% of aqueous modified polybutadiene resin, 22-27% of Al(HCO3)3 modified bentonite composite, 18-23% of water, MnO2 and (CTAB)3PW containing bentonite 12 O 40 Modified ZnO based composite 10-13%, Al2[Si4O 10 ](OH)2 powder 20-26% are mixed and stirred uniformly in a container to form a foundry coating.

3. A method of preparing a coating for casting according to claim 2, characterized in that, The MnO2 and bentonite containing (CTAB)3PW 12 O 40 The modified ZnO-based composite preparation comprises the following steps: Step one, take the bentonite added amount is (CTAB) 3PW 12 O 40 3-9% of the weight, take the zinc salt ZnSO4, prepare into an aqueous solution containing ZnSO4 50-60 g / L, then add 2 times of ZnSO4 molar amount of NaOH, stir the solution by a stirrer (10) for 2-5 minutes to obtain a mixed solution; Step two, add MnO2 powder and (CTAB)3PW containing bentonite to the mixture obtained in step one 12 O 40 powder, and then continue stirring for 0.5-1 h, and then wash the precipitate with distilled water and anhydrous ethanol for 2-3 times, respectively; Step three, put the precipitate washed in step two into a drying oven and dry for 0.5-1 h, then calcine at 400-500 °C for 2-4 h to obtain MnO2 and bentonite containing (CTAB)3PW 12 O 40 Modified ZnO-based composite powder.

4. A method of preparing a coating for casting according to claim 3, characterized in that, MnO2 and bentonite containing (CTAB)3PW 12 O 40 The amount of powder added is 4-9% by weight of ZnO, MnO2 and bentonite containing (CTAB)3PW 12 O 40 The weight ratio of the powder is 1:1.1-1.

3.

5. A method of preparing a coating for casting according to claim 3, characterized in that, The preparation of the MnO2 powder comprises the following steps: Step one, respectively take 3.5g MnSO4·H2O, 2.6g (NH4)2SO4, 9.5g (NH4)2S2O8, dissolve in 400mL deionized water, stir the machine (10) to stir until there is no precipitate and no impurities in the solution, get the mixed solution; Step two, transfer the mixed solution to 1000mL reaction kettle, place the reaction kettle in 140℃ environment for 10h, then naturally cool to room temperature, get the precipitate; Step three, filter and wash the precipitate obtained in the reaction kettle several times to get MnO2 powder.

6. A method of preparing a coating for casting according to claim 2, characterized in that, The bentonite-containing (CTAB)3PW 12 O 40 The powder preparation comprises the following steps: Step one, add 0.5mol of CTAB in 1000ml of ethanol and 1000ml of water, stir the machine (10) for 15min, then add 0.5mol of CTAB, stir for 15min, continue to add 0.165mol of phosphotungstic acid, stir under the condition of reaction for 3-5min, get the mixed solution; Step two, put bentonite powder into the mixed solution obtained from step two, continue to stir for 1 h, stand for 30 min at 50 °C, wash with ethanol, perform suction filtration, and dry at 50 °C to obtain (CTAB)3PW containing bentonite powder 12 O 40 powder.

7. A method of preparing a coating for casting according to claim 2, characterized in that, The preparation of the Al(HCO3)3 modified bentonite composite material comprises the following steps: Step one, according to the proportion of Al(HCO3)3 and bentonite of 3:100, add water according to the solid-liquid weight ratio of 2:5-8, stir the machine (10) until uniform, get the mixed solution; Step two, to the mixture obtained in step one, add Al(HCO3)3, bentonite mixture weight of 2.3-2.7% of Al2[Si4O 10 ](OH)2powder, then stir for 25-30 min, incubate at 75-105℃ for 13-15 h, then filter, dry to obtain Al(HCO3)3modified bentonite composite material.

8. A method of preparing a coating for casting according to claim 7, characterized in that, The composite material is ground to 200-325 mesh in step two, the Al(HCO3)3 modified bentonite composite material, Al(HCO3)3, MnO2 and (CTAB)3PW containing bentonite 12 O 40 The modified ZnO-based composite, Al2[Si4O 10 The particle size of the Al2[Si4O10](OH)2 powder is 200-325 mesh.

9. The method of preparing a coating for casting according to claim 3, characterized in that, The top of the stirring machine (10) is connected with a first motor (11), the output shaft of the first motor (11) is connected with a stirring shaft (12), and the outer surface of the stirring shaft (12) is sequentially installed with a plurality of stirring blades (13) from top to bottom; The inside of the stirring machine (10) is provided with a filter screen (14), the filter screen (14) and the inner wall of the stirring machine (10) and the outer surface of the stirring shaft (12) are connected in sliding mode, and the filter screen (14) is connected with a shaking mechanism (15).

10. A method of preparing a coating for casting according to claim 9, characterized in that, The shaking mechanism (15) comprises a plurality of lifting rods (151) installed on the upper surface of the filter screen (14), a cam (152) abutting with one end of the lifting rod (151) extending to the outside, and a second motor (153) connected with the cam (152), and the second motor (153) is installed on the upper surface of the stirring machine (10).

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