Hydrogel-based fluid abrasive material for abrasive flow finishing processing and preparation method of hydrogel-based fluid abrasive material

Abstract

The invention aims to provide a hydrogel-based fluid abrasive material for abrasive particle flow finishing processing and a preparation method, and belongs to the technical field of polishing abrasive materials, the fluid abrasive material comprises the following components by mass: 30%-50% of abrasive particles, 40%-60% of a matrix solution, 0.3%-6% of a cross-linking agent, 0.1%-1% of a thickening agent, 1%-10% of a preservative, and 1%-5% of lubricating oil, the preparation method comprises the following steps: preparing the hydrogel-based fluid abrasive material for abrasive particle flow finishing processing, the preparation method comprises the following steps: stirring a guar gum / polyvinyl alcohol / glycerol matrix solution under a certain condition, heating to react, adding a cross-linking agent and a thickening agent, generating hydrogel with two macromolecules by a chemical cross-linking method, and finally adding a preservative, lubricating oil and abrasive particles to prepare the hydrogel-based fluid abrasive with viscoelasticity. The prepared abrasive material is good in fluidity and stability, free of pollution, low in cost, easy to degrade and good in surface quality improvement effect, and can be widely applied to the technical field of abrasive flow finishing machining.

Description

Technical Field

[0001] The invention belongs to the technical field of polishing abrasives, and in particular relates to a hydrogel-based fluid abrasive for abrasive flow finishing and a preparation method thereof. Background Art

[0002] Abrasive flow finishing technology is a finishing technology that uses viscoelastic fluid abrasive media to flow through the workpiece surface under pressure, and the abrasive repeatedly cuts it to improve the surface integrity of the workpiece. As an important tool for abrasive flow finishing, the performance of fluid abrasive determines its processing effect. Generally, it is required to have the following characteristics: no sticking to the workpiece wall; easy to carry abrasive particles, with a high viscoelastic adjustment range; good temperature adaptability; good surface improvement effect; non-corrosive, green and environmentally friendly.

[0003] At present, the fluid abrasives used in the market include imported abrasives and domestic abrasives. Most imported abrasives are expensive, the formula is confidential, and it is difficult to adjust according to actual production needs. Domestic abrasives have problems such as easy sticking to the wall, difficulty in adjusting viscoelasticity, difficulty in degradation, and the production process produces toxic gases that harm the environment, which limits the development of domestic abrasive flow finishing technology.

[0004] The Chinese patent application number 201911342332.7 discloses a composite fluid abrasive and a preparation method thereof, which uses silicone oil as a matrix, cubic boron nitride as abrasive, one or more of hydrogenated silicone oil, hydroxy silicone oil and organotin as chain extenders, silane coupling agents and / or titanate coupling agents as coupling agents, and one or more of white oil, liquid paraffin and vaseline as lubricants, and is added to a reactor for stirring and heating to react to obtain a composite fluid abrasive. Although the addition of chain extenders and coupling agents increases the chemical bonding force between the abrasive and the matrix, the viscoelastic adjustment range of the abrasive prepared with silicone oil as the matrix is ​​low, the applicability of the abrasive is poor, and it is difficult to carry abrasives with a larger mesh size to achieve finishing of high-roughness surfaces.

[0005] The Chinese patent with application number 202110343614.X discloses a viscoelastic fluid soft abrasive for abrasive flow finishing of difficult-to-process material surfaces. Methyl vinyl silicone rubber is used as the matrix, and alkyl silicone oil, white oil, dimethyl silicone oil, paraffin, sodium stearate and abrasive particles are added to mix. The prepared abrasive has good viscoelasticity and fluidity, and does not adhere to the workpiece. However, the preparation process of methyl vinyl silicone rubber needs to be carried out at high temperature, which will release toxic gases, which is harmful to operators and the environment. In addition, the abrasive has poor fluidity and is easy to remain on the inner surface of the workpiece, making it difficult to clean. Summary of the invention

[0006] In view of the above problems, the present invention aims to provide a hydrogel-based fluid abrasive, which introduces two high molecular polymers and prepares a hydrogel matrix through water, a crosslinking agent, and a thickener. The hydrogel matrix is ​​a double network entangled structure, which improves the adhesion between the abrasive and the matrix, making the abrasive not easy to fall off during processing. The preparation process is carried out below 100°C, and the prepared abrasive is easy to degrade, simple to operate, low in cost, and environmentally friendly.

[0007] The present invention adopts the following technical solution: A hydrogel-based fluid abrasive for abrasive flow finishing, comprising the following components in mass percentage: 30% to 50% abrasive, 40% to 60% matrix solution, 0.3% to 6% cross-linking agent, 0.1% to 1% thickener, 1% to 10% preservative, and 1% to 5% lubricating oil; The matrix solution is a mixed aqueous solution of guar gum, polyvinyl alcohol and glycerol, and the mass ratio of the guar gum, polyvinyl alcohol and glycerol is (0.27-0.4): (0.608-1.03): (1.2-4.5).

[0008] Furthermore, the particle size of the abrasive grains is 40-300 meshes, and the abrasive grains include one or more of silicon carbide, boron carbide and white corundum.

[0009] Furthermore, the cross-linking agent is sodium tetraborate.

[0010] Furthermore, the thickener is fumed silica, the particle size of the fumed silica is 7-40 nm, and the specific surface area is 50-380 m 2 / g.

[0011] Furthermore, the preservative includes one or both of potassium sorbate and kasone.

[0012] Furthermore, the lubricating oil is dimethyl silicone oil with a viscosity of 1000 cs.

[0013] A method for preparing a hydrogel-based fluid abrasive for abrasive flow finishing, comprising the following steps: The first step is to prepare a matrix solution: dissolve guar gum powder in glycerin, add distilled water to prepare a guar gum / glycerin / water solution, dissolve polyvinyl alcohol particles in distilled water to prepare a polyvinyl alcohol solution, mix to obtain a guar gum / polyvinyl alcohol / glycerin aqueous solution, stir and heat to react, and after the reaction is completed, obtain a matrix solution; The second step is the preparation of fluid abrasives: after the base solution is cooled, a cross-linking agent and a thickener are added, and the hydrogel base is obtained by heating and stirring. Finally, a preservative, a lubricating oil and abrasive particles are added to obtain a hydrogel-based fluid abrasive.

[0014] Furthermore, the mass concentration of the polyvinyl alcohol solution in the first step is 8-10%.

[0015] Furthermore, the heating reaction temperature in the first step is 60-90°C and the time is 1-2h; the heating temperature in the second step is 25-30°C and the time is 0.5-1h.

[0016] The beneficial effects of the present invention are as follows: The hydrogel structure of the present invention can carry abrasive particles better, and the abrasive particles are not easy to fall off during processing. The preparation process of the fluid abrasive is green and environmentally friendly, no irritating gas is generated, the abrasive has good viscoelasticity, and has a high material removal ability. The prepared fluid abrasive is easy to degrade, low in cost, and environmentally friendly, and can be widely used in abrasive flow finishing processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a physical picture of the hydrogel-based fluid abrasive prepared in the present invention. DETAILED DESCRIPTION

[0018] Example 1 The fluid abrasive of this embodiment is prepared from the following raw materials in mass percentage: 50% silicon carbide abrasive, 0.37% guar gum, 10.3% 10wt% polyvinyl alcohol solution, 1.2% glycerol, 34.88% distilled water, 0.6% sodium tetraborate, 0.25% fumed silica, 1.2% potassium sorbate, and 1.2% silicone oil.

[0019] The specific process of the preparation method of the matrix solution of this embodiment is as follows: guar gum powder is dissolved in glycerol, distilled water is added to prepare a guar gum / glycerol / water solution, the solution is poured into a 10 wt % polyvinyl alcohol solution, and the mixture is stirred and heated to 90° C. for reaction for 1 hour.

[0020] The specific process of the preparation method of the hydrogel-based fluid abrasive in this embodiment is as follows: after the matrix solution is cooled, sodium tetraborate and fumed silica are added, heated and stirred at 25° C. for 0.5 h to obtain a hydrogel matrix, and then potassium sorbate, silicone oil, and black silicon carbide abrasive particles are mixed to obtain a hydrogel-based fluid abrasive.

[0021] After testing, the hydrogel-based fluid abrasive of this embodiment has excellent viscoelasticity and abrasive carrying capacity. After abrasive flow processing of a stainless steel slender tube using the fluid abrasive of this embodiment, the performance of the fluid abrasive after processing is stable and does not stick to the workpiece surface.

[0022] Example 2 The fluid abrasive of this embodiment is prepared from the following raw materials in percentage by mass: 40% silicon carbide abrasive grains, 0.4% guar gum, 10% 10wt% polyvinyl alcohol solution, 4% glycerol, 39.83% distilled water, 0.5% sodium tetraborate, 0.27% fumed silica, 1% kason, 2% potassium sorbate, and 2% silicone oil.

[0023] The specific process of the preparation method of the matrix solution in this embodiment is the same as that in Example 1.

[0024] The specific process of the preparation method of the hydrogel-based fluid abrasive in this embodiment is as follows: after the matrix solution is cooled, sodium tetraborate and fumed silica are added, heated and stirred at 30° C. for 0.5 h to obtain a hydrogel matrix, and then potassium sorbate, kason, silicone oil, and black silicon carbide abrasive particles are mixed to obtain a hydrogel-based fluid abrasive.

[0025] After testing, the hydrogel-based fluid abrasive of this embodiment has excellent viscoelasticity and abrasive carrying capacity. After abrasive flow processing of a stainless steel slender tube using the fluid abrasive of this embodiment, the performance of the fluid abrasive after processing is stable and does not stick to the workpiece surface.

[0026] Example 3 The fluid abrasive of this embodiment is prepared from the following raw materials in percentage by mass: 38% silicon carbide abrasive grains, 0.27% guar gum, 7.6% 8wt% polyvinyl alcohol solution, 4.5% glycerol, 44.98% distilled water, 1.5% sodium tetraborate, 0.15% fumed silica, 1.5% kason, and 1.5% silicone oil.

[0027] The specific process of the preparation method of the matrix solution in this embodiment is as follows: guar gum powder is dissolved in glycerol, distilled water is added to prepare a guar gum / glycerol / water solution, the solution is poured into an 8 wt % polyvinyl alcohol solution, and the mixture is stirred and heated to 60° C. for reaction for 2 h.

[0028] The specific process of the preparation method of the hydrogel-based fluid abrasive in this embodiment is as follows: after the matrix solution is cooled, sodium tetraborate and fumed silica are added, heated and stirred at 25° C. for 1 hour to obtain a hydrogel matrix, and then mixed with kason, silicone oil, and black silicon carbide abrasive particles to obtain a hydrogel-based fluid abrasive.

[0029] After testing, the hydrogel-based fluid abrasive of this embodiment has excellent viscoelasticity and abrasive carrying capacity. After abrasive flow processing of a stainless steel slender tube using the fluid abrasive of this embodiment, the performance of the fluid abrasive after processing is stable and does not stick to the workpiece surface.

[0030] Comparative Example 1 The fluid abrasive of this comparative example is prepared from the following raw materials in percentage by mass: 50% silicon carbide abrasive grains, 10% 10wt% polyvinyl alcohol solution, 3% glycerol, 31.85% distilled water, 2% sodium tetraborate, 0.15% fumed silica, 1.5% potassium sorbate, and 1.5% silicone oil.

[0031] The specific process of the preparation method of the matrix solution of this comparative example is: dissolving glycerol in distilled water to prepare a glycerol / water solution, pouring it into a 10wt% polyvinyl alcohol solution, stirring and heating to 90°C to react for 1h.

[0032] The specific process of the preparation method of the hydrogel-based fluid abrasive in this comparative example is: after the matrix solution is cooled, sodium tetraborate and fumed silica are added, heated and stirred at 25°C for 1 hour to obtain a single-network hydrogel matrix, and then potassium sorbate, silicone oil, and black silicon carbide abrasive particles are mixed to obtain a single-network hydrogel-based fluid abrasive.

[0033] After testing, it was found that the hydrogel-based fluid abrasive in this comparative example was a single-network hydrogel with low viscoelasticity and could not meet normal use requirements.

[0034] Comparative Example 2 The fluid abrasive of this embodiment is prepared from the following raw materials in percentage by mass: 40% silicon carbide abrasive grains, 0.6% guar gum, 6% glycerol, 48.2% distilled water, 2% sodium tetraborate, 0.2% fumed silica, 1.5% kason, and 1.5% silicone oil.

[0035] The specific process of the preparation method of the matrix solution of this comparative example is: dissolving guar gum powder in glycerol, adding distilled water to prepare a guar gum / glycerol / water solution, stirring and heating to 90° C. to react for 1.5 hours.

[0036] The specific process of the preparation method of the hydrogel-based fluid abrasive in this comparative example is: after the matrix solution is cooled, sodium tetraborate and fumed silica are added, heated and stirred at 30°C for 0.5h to obtain a single-network hydrogel matrix, and then mixed with kason, silicone oil, and black silicon carbide abrasive particles to obtain a single-network hydrogel-based fluid abrasive.

[0037] After testing, the hydrogel-based fluid abrasive in this comparative example is a single-network hydrogel with moderate viscoelasticity, but poor adhesion between the matrix and the abrasive. When the fluid abrasive in this embodiment is used to perform abrasive flow processing on a stainless steel slender tube, the abrasive is prone to fall off during the processing, and the surface quality improvement effect is poor, which cannot meet normal use requirements.

[0038] Comparative Example 3 The fluid abrasive of this embodiment is prepared from the following raw materials in percentage by mass: 30% silicon carbide abrasive grains, 0.49% guar gum, 8.2% 10wt% polyvinyl alcohol solution, 5% glycerol, 54.35% distilled water, 0.8% sodium tetraborate, 0.16% fumed silica, 0.5% potassium sorbate, and 0.5% silicone oil.

[0039] The specific process of the preparation method of the matrix solution in this comparative example is the same as that in Example 1.

[0040] The specific process of the preparation method of the hydrogel-based fluid abrasive in this comparative example is the same as that in Example 1.

[0041] After testing, the double-network hydrogel-based fluid abrasive in this comparative example has good viscoelasticity and abrasive carrying capacity, but it sticks to the surface of the workpiece and cannot meet normal use requirements.

[0042] Performance Testing The prepared hydrogel-based fluid abrasive was used to perform abrasive flow machining on a stainless steel slender tube, and the surface roughness Ra value was measured by a MarSurf M400 roughness meter.

[0043] Table 1 Performance test results Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention 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 invention.

Claims

1. A hydrogel-based fluid abrasive for abrasive flow finishing, characterized in that: The composition comprises the following components in mass percentage: 30% to 50% abrasive grains, 40% to 60% matrix solution, 0.3% to 6% cross-linking agent, 0.1% to 1% thickener, 1% to 10% preservative, and 1% to 5% lubricating oil; The matrix solution is a mixed aqueous solution of guar gum, polyvinyl alcohol and glycerol, and the mass ratio of the guar gum, polyvinyl alcohol and glycerol is (0.27-0.4): (0.608-1.03): (1.2-4.5).

2. The hydrogel-based fluid abrasive for abrasive flow finishing according to claim 1, characterized in that: The particle size of the abrasive grains is 40-300 meshes, and the abrasive grains include one or more of silicon carbide, boron carbide and white corundum.

3. The hydrogel-based fluid abrasive for abrasive flow finishing according to claim 1, characterized in that: The cross-linking agent is sodium tetraborate.

4. The hydrogel-based fluid abrasive for abrasive flow finishing according to claim 1, characterized in that: The thickener is fumed silica, the particle size of the fumed silica is 7-40 nm, and the specific surface area is 50-380 m 2 / g.

5. The hydrogel-based fluid abrasive for abrasive flow finishing according to claim 1, characterized in that: The preservatives include one or both of potassium sorbate and kasone.

6. The hydrogel-based fluid abrasive for abrasive flow finishing according to claim 1, characterized in that: The lubricating oil is dimethyl silicone oil with a viscosity of 1000 cs.

7. A method for preparing a hydrogel-based fluid abrasive for abrasive flow finishing as claimed in claim 1, characterized in that: The steps include: The first step is to prepare a matrix solution: dissolve guar gum powder in glycerin, add distilled water to prepare a guar gum / glycerin / water solution, dissolve polyvinyl alcohol particles in distilled water to prepare a polyvinyl alcohol solution, mix to obtain a guar gum / polyvinyl alcohol / glycerin aqueous solution, stir and heat to react, and after the reaction is completed, obtain a matrix solution; The second step is the preparation of fluid abrasives: after the base solution is cooled, a cross-linking agent and a thickener are added, and the hydrogel base is obtained by heating and stirring. Finally, a preservative, a lubricating oil and abrasive particles are added to obtain a hydrogel-based fluid abrasive.

8. The method for preparing a hydrogel-based fluid abrasive for abrasive flow finishing according to claim 7, characterized in that: The mass concentration of the polyvinyl alcohol solution in the first step is 8-10%.

9. The method for preparing a hydrogel-based fluid abrasive for abrasive flow finishing according to claim 7, characterized in that: The heating reaction temperature in the first step is 60-90°C for 1-2 hours; the heating temperature in the second step is 25-30°C for 0.5-1 hour.

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