CN113583746A - Antirust grinding fluid for bonded neodymium-iron-boron magnet and preparation method thereof - Google Patents

Abstract

The invention provides an antirust grinding fluid for a bonded neodymium iron boron magnet and a preparation method thereof, wherein the antirust grinding fluid comprises the following components in percentage by mass: 3-10% of an antirust agent; 0.5-2.0% triethanolamine; 0.5-2.0% of polyether; 0.1-0.6% of defoaming agent; 0.05-0.3% of preservative; the balance being water. According to the invention, the environment-friendly biodegradable water-based antirust agent is used for replacing sodium nitrite in the traditional formula, so that the antirust grinding fluid has better environment-friendly performance; meanwhile, the antirust grinding fluid is applied to the wet chamfering process of the bonded neodymium iron boron magnet, so that the corners of the processed magnet workpiece are rounded and the antirust performance is excellent.

Description

Antirust grinding fluid for bonded neodymium-iron-boron magnet and preparation method thereof

Technical Field

The invention relates to the technical field of grinding fluid, in particular to an antirust grinding fluid for bonded neodymium iron boron magnets and a preparation method thereof.

Background

After the bonded neodymium iron boron magnet is subjected to compression molding and curing, sharp edges can be generated at corners, edges and the like, and the corrosion resistance of the magnet after electrophoresis and roll-spraying coating can be greatly reduced due to the sharp edges, and the subsequent installation of the magnet and the application after installation are also seriously influenced. In order to avoid the adverse effects, the magnet after being pressed and formed is usually required to be polished, chamfered and edge-removed by using an abrasive material, the chamfering process comprises a dry grinding method and a wet grinding method, the dry grinding method is to directly grind the magnet by using a brown corundum abrasive material without adding grinding fluid, although the method can prevent the magnet from rusting, the edge and corner of the magnet are easily removed due to poor chamfering strength; the wet grinding is to add proper aqueous grinding fluid into the brown corundum abrasive, so that the corners and edges of the workpiece can be protected from being lost in the grinding process, and the rusting of the workpiece in the grinding process can be prevented.

The traditional grinding fluid is prepared by adding sodium nitrite into a formula for rust prevention, and the sodium nitrite serving as a rust inhibitor has a good effect, but has a carcinogenic effect and is not beneficial to environmental protection.

Disclosure of Invention

The invention aims to provide an antirust grinding fluid for a bonded neodymium iron boron magnet and a preparation method thereof, aiming at the defects of the prior art. The antirust grinding fluid is prepared by adopting naturally degradable environment-friendly raw materials instead of sodium nitrite in the traditional formula, and is environment-friendly.

In order to achieve the purpose, the invention provides an antirust grinding fluid for a bonded neodymium iron boron magnet, which comprises the following components in percentage by mass:

preferably, the composition comprises the following components in percentage by mass:

in one embodiment, the water is pure water, and the conductivity of the pure water is less than or equal to 10 mu S/cm.

In one embodiment, the antirust agent is one or more of triethanolamine oleate borate, alkanolamine oleate, phytic acid, sebacic acid and organic ternary polycarboxylic acid.

In one embodiment, the defoamer is one or more of a silicone defoamer, a polyether defoamer, or a polyether modified silicon defoamer.

In one embodiment, the polyether is one or more of polyether L61, polyether L62, and polyether L64.

In one embodiment, the anti-corrosion agent further comprises trisodium phosphate, and the weight percentage of the trisodium phosphate is 0.2-1.5%.

In one embodiment, the corrosion inhibitor is triethyl oleate soap.

On the other hand, the invention provides a preparation method of the antirust grinding fluid for the bonded neodymium iron boron magnet, which comprises the following steps:

adding water, an antirust agent and triethanolamine into a reaction kettle, and heating for reaction until a transparent clear solution is formed;

removing the heat source, adding polyether, and continuously stirring until the solution is uniform;

and cooling the solution to room temperature, adding water, a defoaming agent and a preservative, mixing, and continuously stirring until the system is uniform to obtain the antirust grinding fluid.

In one embodiment, the temperature of the heating reaction is 75-85 ℃.

The invention has the beneficial effects that:

firstly, the invention abandons the scheme of adopting sodium nitrite as an antirust component in the traditional formula, and selects and replaces the environment-friendly aqueous antirust agent, and the aqueous antirust agent can be degraded in natural environment and is environment-friendly; secondly, the antirust agent is compounded by a plurality of water-based antirust agents, so that the antirust effect of the antirust grinding fluid is improved; thirdly, a certain amount of corrosion inhibitor is added in the invention to further improve the rust-proof and corrosion-proof performance; moreover, the chamfering method is used for the chamfering process of the bonded neodymium iron boron magnet, and after the chamfering process is ground, the corners of the magnet workpiece are rounded and the rust resistance is excellent.

Detailed Description

The following examples are provided to further illustrate the embodiments of the present invention.

The following description of the embodiments of the present invention is provided by way of specific examples, and other advantages and effects of the present invention will be readily apparent to those skilled in the art from the disclosure herein. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention. It is to be noted that the features in the following embodiments and examples may be combined with each other without conflict. It is also to be understood that the terminology used in the examples is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention. Test methods in which specific conditions are not specified in the following examples are generally carried out under conventional conditions or under conditions recommended by the respective manufacturers.

When numerical ranges are given in the examples, it is understood that both endpoints of each of the numerical ranges and any value therebetween can be selected unless the invention otherwise indicated. Unless defined 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 invention belongs and the description of the present invention, and any methods, apparatuses, and materials similar or equivalent to those described in the examples of the present invention may be used to practice the present invention.

Note that "%" and "part(s)" shown in the description herein mean "% by mass" and "part(s) by mass", respectively, unless otherwise specified.

The invention provides an antirust grinding fluid for a bonded neodymium iron boron magnet, which comprises the following components in percentage by mass: 3-10% of an antirust agent; 0.5-2.0% of triethanolamine; 0.5-2.0% of polyether; 0.1-0.6% of defoaming agent; 0.05-0.3% of preservative; the balance being water.

In some embodiments, the components have more preferred mass percentages, such as: 4-6% of an antirust agent; 0.9-1.2% of triethanolamine; 0.9-1.2% of polyether; 0.1-0.3% of defoaming agent; 0.08-0.12% of preservative; the balance being water.

In some embodiments, the formula of the antirust grinding fluid for the bonded neodymium iron boron magnet can further contain trisodium phosphate, and the weight percentage of the trisodium phosphate is 0.2-1.5%.

In some embodiments, the formulation of the rust-proof grinding fluid for bonding neodymium-iron-boron magnets may further contain a corrosion inhibitor, for example, a triethyl oleate corrosion inhibitor.

The invention provides a preparation method of an antirust grinding fluid for bonding neodymium iron boron magnets, which comprises the following steps:

s1, adding water, an antirust agent and triethanolamine into a reaction kettle, and heating for reaction until a transparent clear solution is formed;

s2, removing the heat source, adding polyether, and continuing stirring until the solution is uniform;

s3, cooling the solution to room temperature, adding water, a defoaming agent and a preservative, mixing, and continuously stirring until the system is uniform to obtain the antirust grinding fluid.

In a specific embodiment, the water in step S1 can be, for example, pure water, the conductivity of which is ≦ 10 μ S/cm.

In a specific embodiment, the rust inhibitor in step S1 may be one or more of triethanolamine borate oleate, alkanolamine oleate, phytic acid, sebacic acid, and organic triprotic polycarboxylic acid. For example, triethanolamine oleate borate can be selected as the antirust agent, and for example, triethanolamine oleate borate and alkanolamine oleate can be selected to be compounded as the antirust agent of the grinding fluid, and for example, triethanolamine oleate borate and organic ternary polycarboxylic acid can be selected to be compounded as the antirust agent of the grinding fluid. The antirust agent of the grinding fluid adopts a water-based antirust agent to replace sodium nitrite in the traditional formula, and the water-based antirust agent can be naturally degraded in the environment and is environment-friendly. And the acid triethanolamine borate is added into the grinding fluid as an antirust agent, has an excellent antirust effect on metal materials, can form a protective film on the surface of a workpiece, and can increase the lubricating property of the grinding fluid.

In one embodiment, the reaction temperature of the heating reaction of the water, the rust inhibitor and the triethanolamine in the step S1 may be 75 to 90 ℃.

In different embodiments, trisodium phosphate may be further added in step S1, and the mass percentage of the added trisodium phosphate may be, for example, 0.2 to 1.5%, specifically, 0.5%, 0.7%, and 0.9% of trisodium phosphate may be added to enhance the degreasing capability of the grinding fluid.

In different embodiments, triethyl oleate soap can be added as a corrosion inhibitor in the step S1, so that the antirust and anticorrosive performance of the grinding fluid is further improved.

In various embodiments, the polyether in step S2 may be one or more of polyether L61, polyether L62, and polyether L64. For example, in one preferred embodiment, the polyether in S2 can be selected from polyether L64, and in yet another preferred embodiment, the polyether in S2 can be selected from a mixture of polyether L62 and polyether L64.

In various embodiments, the defoamer described in step S3 may be one or more of a silicone defoamer, a polyether defoamer, or a polyether modified silicon defoamer, and more specifically, may be, for example, a DF-682 defoamer.

The present invention will be described in detail with reference to the following examples.

Example 1

The rust-proof grinding fluid for the bonded neodymium iron boron magnet is prepared from the following raw materials according to the following formula:

table 1 example 1 ingredient table

Adding triethanolamine boric acid oleate, triethanolamine, trisodium phosphate and part of pure water into a reaction kettle, heating to 85 ℃, and reacting to form a transparent clear solution; then removing the heat source, adding polyether L64, and continuously stirring until the solution is uniform; and finally, cooling the solution to room temperature, adding the defoaming agent DF-682, the preservative BK and the residual pure water, and continuously stirring until the system is uniform to obtain the antirust grinding fluid.

Example 2

The rust-proof grinding fluid for the bonded neodymium iron boron magnet is prepared from the following raw materials according to the following formula:

table 2 example 2 ingredient table

Name of raw materials	Dosage (kg)	Specification of	Brand
				Oleic acid Triethanolamine boric acid	6	Industrial scale (200 kg/barrel)	Chemical Co Ltd of Yongtai Jinan
Triethanolamine	1.2	Industrial grade	/
				Polyether L64	1	Industrial scale (50 kg/barrel)	Jiangsu Hai'an petrochemical plant
Trisodium phosphate	0.8	Industrial grade	/
				Defoaming agent DF-682	0.3	Industrial grade (60 kg/barrel)	DONGGUAN DEFENG DEFOAMER Co.,Ltd.
Preservative BK	0.1	/	Beijing Nanda Dahe Rong science and technology development Co Ltd
				Pure water	90.6	The conductivity is less than or equal to 10 mu S/cm	/

Adding triethanolamine boric acid oleate, triethanolamine, trisodium phosphate and part of pure water into a reaction kettle, heating to 85 ℃, and reacting to form a transparent clear solution; then removing the heat source, adding polyether L64, and continuously stirring until the solution is uniform; and finally, cooling the solution to room temperature, adding the defoaming agent DF-682, the preservative BK and the residual pure water, and continuously stirring until the system is uniform to obtain the antirust grinding fluid.

Example 3

The rust-proof grinding fluid for the bonded neodymium iron boron magnet is prepared from the following raw materials according to the following formula:

table 3 example 3 ingredient table

Adding triethanolamine boric acid oleate, triethanolamine, trisodium phosphate, triethanolamine oleate soap and part of pure water into a reaction kettle, heating to 85 ℃, and reacting to form a transparent clear solution; then removing the heat source, adding polyether L64, and continuously stirring until the solution is uniform; and finally, cooling the solution to room temperature, adding the defoaming agent DF-682, the preservative BK and the residual pure water, and continuously stirring until the system is uniform to obtain the antirust grinding fluid.

The above-mentioned rust-preventive grinding liquids of examples 1 to 3, tap water and pure water were applied to the wet chamfering process of bonded ndfeb magnets, respectively, and the polishing effect and rust-preventive property were measured, and the comparison results are shown in the following table:

TABLE 4 glossing and anticorrosive effects of examples 1 to 3 and comparative examples

Medium	Effect of light decoration	Antirust effect	Remarks for note
				Example 1 grinding fluid	The edge and corner of the magnet do not drop slag	The surface of the magnet is free of rust after being naturally placed in the air for 5 days
EXAMPLE 2 grinding fluid	The edge and corner of the magnet do not drop slag	The surface of the magnet is free of rust after being naturally placed in the air for 5 days
				EXAMPLE 3 grinding fluid	The edge and corner of the magnet do not drop slag	The surface of the magnet is free of rust after being naturally placed in the air for 5 days
Tap water	Magnet edge and corner slag removal	The surface of the magnet is seriously rusted after being naturally placed in the air for 1 day
				Pure water	Slight slag falling of magnet corners and edges	The surface of the magnet is slightly rusted after the magnet is naturally placed in the air for 1 day	The conductivity is less than or equal to 10 mu S/cm

As can be seen from the table, the antirust grinding fluid disclosed by the invention has excellent grinding performance and antirust performance on bonded neodymium iron boron magnets.

While the invention has been described with reference to specific embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. Those skilled in the art can make various changes, modifications and equivalent arrangements to those skilled in the art without departing from the spirit and scope of the invention, which should be construed as broadly as the invention; meanwhile, any changes, modifications and variations of the above-described embodiments, which are equivalent to those of the technical spirit of the present invention, are within the scope of the technical solution of the present invention.

Claims (10)

1. The rust-proof grinding fluid for the bonded neodymium-iron-boron magnet is characterized by comprising the following components in percentage by mass:

2. the antirust grinding fluid for the bonded neodymium-iron-boron magnet according to claim 1 is characterized by comprising the following components in percentage by mass:

3. the antirust grinding fluid for bonded neodymium-iron-boron magnets according to claim 1, wherein the water is pure water, and the conductivity of the pure water is less than or equal to 10 μ S/cm.

4. The rust-proof grinding fluid for the bonded neodymium iron boron magnet according to claim 1, wherein the rust-proof agent is one or more of triethanolamine oleate borate, alkanolamine oleate, phytic acid, sebacic acid and organic ternary polycarboxylic acid.

5. The antirust grinding fluid for the bonded neodymium iron boron magnet according to claim 1, wherein the defoaming agent is one or more of an organic silicon defoaming agent, a polyether defoaming agent or a polyether modified silicon defoaming agent.

6. The antirust grinding fluid for bonded neodymium iron boron magnets according to claim 1, wherein the polyether is one or more of polyether L61, polyether L62 and polyether L64.

7. The antirust grinding fluid for the bonded neodymium-iron-boron magnet according to claim 1, further comprising trisodium phosphate, wherein the mass percentage of the trisodium phosphate is 0.2-1.5%.

8. The antirust grinding fluid for the bonded neodymium-iron-boron magnet according to claim 1, further comprising a corrosion inhibitor, wherein the corrosion inhibitor is triethyl oleate soap.

9. The method for preparing the rust-proof grinding fluid for the bonded neodymium-iron-boron magnet according to any one of claims 1 to 6, characterized by comprising the following steps:

adding water, an antirust agent and triethanolamine into a reaction kettle, and heating for reaction until a transparent clear solution is formed;

removing the heat source, adding polyether, and continuously stirring until the solution is uniform;

and cooling the solution to room temperature, adding water, a defoaming agent and a preservative, mixing, and continuously stirring until the system is uniform to obtain the antirust grinding fluid.

10. The preparation method of the antirust grinding fluid for the bonded neodymium iron boron magnet according to claim 9, wherein the temperature of the heating reaction is 75-85 ℃.