KR20220008580A - High performance eco-friendly one-component surface treatment agent for cold forging process - Google Patents

Abstract

The present invention relates to a surface treatment agent composition for cold forging, including: a polymer binder including an acrylic acid-based polymer and phosphorous oxide in a weight ratio of 1:10 to 4:10 and having a pH of 3 to 5; one or more dispersants selected from a group consisting of anionic, cationic, amphoteric and nonionic dispersants; and one or more lubricity improvers selected from a group consisting of molybdenum disulfide, graphite, and wax.

Description

High performance eco-friendly one-component surface treatment agent for cold forging process

The present invention relates to an environmentally friendly one-component cold forging surface treatment agent having excellent performance.

The forging process is a metal processing method in which a metal material such as a lump of metal or a thick metal plate is placed between the molds, and the metal material is deformed and molded by pressing and pressing the metal material. Representative examples include hammer and press forging. can For such forging, based on the crystallization temperature of the material to be processed, hot forging is divided into hot forging, if it is within the crystallization temperature range, warm forging, and cold forging from 100° C. or less to room temperature.

In the plastic working of metal materials, the use of lubricants is essential because the metal material as a workpiece and a tool such as a mold rub against each other violently at the friction interface. Lubricants in plastic working of metal materials are interposed in the friction interface to prevent direct metal to metal contact, reduce frictional resistance and contribute to suppression of wear, etc. Affects quality improvement.

The lubricant used in the forging process is a release lubricant composition used for processing metallic and non-ferrous metal materials. It is designed to have both seizure resistance and friction reduction ability under severe conditions such as high surface pressure, pressure load, and surface area expansion. Various types of lubricants for forging are used depending on the material, the viscosity required in the process, the processing precision of the material, the size of the surface pressure, and the subsequent process.

As a lubricant for plastic working, a method of interposing lubricants such as oils, soaps, and waxes at the friction interface is used for light machining. , and there is a problem in that seizures (direct contact between metals) are likely to occur. For this reason, in general, a chemical conversion film for plastic working, in which a chemical conversion film is formed on the surface of a metal material to be processed, and lubricated with soap or the like is performed thereon, is widely used as a lubricant. However, the chemical conversion film for plastic processing is formed after performing about 10 steps such as degreasing, water washing, acid washing, water washing, chemical conversion treatment, water washing, lubricating film formation and drying, etc. , liquid management is required because chemical reactions occurring in each treatment process must be controlled, and a large amount of energy is consumed to maintain the treatment tank at a high temperature. In addition, since a large amount of insoluble salt and waste liquid are generated in the treatment process, it is not preferable from an environmental point of view. Accordingly, the Sumimold process, which reduces the steps by shot blasting, degreasing, cleaning base film, drying, lubricating film formation and drying, etc., has been proposed, but it takes more than 2 hours and generates a large amount of wastewater and waste, There is a problem of consuming a large amount of energy.

Accordingly, it is required to develop a one-component type surface treatment agent for cold forging that can shorten the working time and reduce process energy consumption while reducing the amount of wastewater and waste.

The problem to be solved by the present invention is that it is possible to greatly reduce the working time by shortening the process steps, and it is environmentally friendly because there is little generation of wastewater and waste, and it is economical high-performance eco-friendly one-component cold forging surface because the cost can be dramatically reduced. To provide a treatment composition.

Another object to be solved by the present invention is to provide a method for cold forging of a metal material using the cold forging surface treatment agent composition.

In order to achieve the above object, the present invention includes an acrylic acid-based polymer and phosphorous oxide in a weight ratio of 1:10 to 4:10, a polymer binder having a pH of 3 to 5; one or more dispersants selected from the group consisting of anionic, cationic, amphoteric and nonionic dispersants; And it provides a surface treatment agent composition for cold forging comprising; and molybdenum disulfide, graphite, and any one or more lubricity improvers selected from the group consisting of wax.

In one embodiment of the present invention, the surface agent composition for cold forging can control the content of solids according to the required physical properties, for example, as the surface agent composition for cold forging having a solid content of 35% by weight, 5 g of an acrylic acid-based polymer (acrylic 35 wt% of solids in acid-based polymer; pH 3-5), 27 g of phosphoric oxide (40% of solids in phosphoric oxide, pH 3-5), 0.45 g of dispersant, molybdenum disulfide:graphite:wax in a weight ratio of 10:2:3 22 g of the lubricity improver mixed with the furnace, and the viscosity of the surface agent composition for cold forging may be 100 to 800 cps.

In addition, the present invention for the cold forging process of the molding using the surface treatment agent composition for cold forging, (1) preheating the material to be molded to 40 to 60 ℃; (2) applying and drying the release agent composition for cold forging according to any one of claims 1 to 1 on the surface of the preheated material; And (3) forming the material; provides a method for cold forging of a metal material comprising a.

The cold forging surface treatment agent according to the present invention is a paint-type, one-component lubricant, which greatly reduces the working time by shortening the process step, has excellent performance, and is economical due to low energy consumption during use. In addition, it is eco-friendly because wastewater and waste are hardly generated, and it is industrially advantageous because it improves the quality of forgings, prevents seizure of molds, and increases mold life.

1 is a cross-sectional structure of a surface lubricated surface formed on a material surface for a cold forging process according to an embodiment of the present invention.
Figure 2 is a cross-sectional structure of the surface lubrication treatment formed on the surface of the material for the cold forging process according to the prior art.
Figure 3a shows that after treatment with a surface treatment agent composition for cold forging containing an acrylic acid-based polymer and phosphorous oxide in a weight ratio of 1:10 to 4:10 as a binder, a dimension cutting process is performed (normal; Example), Figure 3b is a schematic diagram of a surface treatment composition for cold forging containing a single component of an acrylic acid-based polymer as a binder, followed by a dimensional cutting process (control group).
Figure 4a shows that the upper end is treated with a surface treatment agent composition for cold forging containing an acrylic acid-based polymer and phosphorous oxide in a weight ratio of 1:10 to 4:10 as a binder, and then a deformation process by press pressure is performed (normal; practice) Example), Figure 4b is a schematic diagram of a process (control group) that was treated with a surface treatment agent composition for cold forging including a single component of an acrylic acid-based polymer as a binder, and then subjected to a deformation process by press pressure.
Figure 5a shows that after treatment with a surface treatment agent composition for cold forging containing an acrylic acid-based polymer and phosphorous oxide in a weight ratio of 1:10 to 4:10 as a binder, a deformation process by extrusion is performed (normal; Example); Figure 5b is a schematic view of a deformation process by extrusion after treatment with a surface treatment agent composition for cold forging including a single component of an acrylic acid-based polymer as a binder (control group).

Hereinafter, the present invention will be described in detail.

The eco-friendly one-component cold forging surface treatment composition of the present invention is used for cold forging during the precision extrusion forging process.

In the conventional cold forging process, the process step is performed in several steps. As a commonly used cold forging process, the sumimold process consists of shot blasting, alkali degreasing, hot water washing, chemical conversion coating (primary coating), hot water cleaning, drying, lubricating coating (secondary coating), drying, and molding. The primary coating film is called a base film and bonderite, and the component is usually a zinc phosphate film layer, which is introduced to increase the film weight to increase moldability, and the secondary film is called a lubricating film, bonderube, and soap lubrication. _{Soda stearate (C 17} H ₃₅ COONa) is placed on the surface layer on the zinc stearate (metal soap) layer due to the film formation. The mechanism for forming a lubricating film (bonda rube) is Zn ₃ (PO ₄ ) ₂ + 6C ₁₇ H ₃₅ COONa → 3Zn(C ₁₇ H ₃₅ COO) ₂ + 2Na ₃ PO ₄ . As shown in FIG. 2, the cross section of the material on which the film is formed is composed of the material - the chemical film - the metal soap layer - the sodium stearate layer. Due to this complicated process, there are problems that the process takes more than 2 hours, generates a large amount of wastewater and waste, and consumes a lot of energy.

On the other hand, the use of the cold forging surface treatment composition according to the present invention shortens the process step, so that the entire process is preheated in the degreasing process of the existing cold forging process, the surface treatment agent (lubricant) is applied and dried, and then the molding process is performed. As shown in FIG. 1, it has a cross section of the material-lubricating film. Specifically, by reducing the process steps of cold forging, the time taken for work can be shortened to 5-10 minutes, energy consumption can be reduced by 75% or more, and there is an advantage in that wastewater and waste are hardly generated.

The present invention includes a polymer binder having an acrylic acid-based polymer and phosphorous oxide in a weight ratio of 1:10 to 4:10 and having a pH of 3 to 5 so as to exhibit extreme pressure properties; one or more dispersants selected from the group consisting of anionic, cationic, amphoteric and nonionic dispersants; And it provides a surface treatment agent composition for cold forging comprising; and molybdenum disulfide, graphite, and any one or more lubricity improvers selected from the group consisting of wax.

In the present invention, the polymer binder is water-soluble, (a) an acrylic acid-based polymer; and (b) a mixture or copolymer of phosphoric oxide.

The (a) acrylic acid-based polymer may be a copolymer of one or more monomers selected from the group consisting of acrylic acid, methacrylic acid, methylmethacrylic acid, maleic acid, silicone acryl, fluoroacrylic acid, acryl phosphate, ethylene and styrene, preferably may have a glass transition temperature of -10 °C to 30 °C. If the glass transition temperature of the acrylic acid polymer is less than -10°C, the film of the lubricant component is too soft and the film is weak, making it difficult to work. If the glass transition temperature exceeds 30°C, the lubricant film is too hard and heat of compression When this occurs, lubricity may decrease and the friction coefficient may increase, which is not preferable. According to the present invention, the preferred viscosity may be 200 to 600 cps in the case of an aqueous solution having a solid content of 10% by weight. Since sedimentation of an inorganic pigment can be prevented as a viscosity is the said range, it is preferable. If the viscosity exceeds the above range, it is difficult to wet the pigment component during operation, and if it is less than the above range, there is a problem in that the sedimentation stability of the pigment component is lowered.

The (b) phosphoric oxide is at least one selected from the group consisting of phosphoric acid esters and polyphosphoric acid compounds, and may have a pH of 1.5-7.5, preferably a pH of 2-5.

The phosphorous oxide according to the present invention is preferably at least one selected from the group consisting of alkyl acid phosphate, dioleyl hydrogen phosphite, polyether phosphate, polyphosphoric acid, pyrophosphoric acid, metaphosphoric acid, or salts thereof, and poly It may be in a neutralized state of sodium phosphate, potassium polyphosphate, amine polyphosphate and ammonium polyphosphate. If the phosphoric oxide is easily hydrolyzed or reacts with the acrylic acid-based polymer, extreme pressure properties may be reduced, but the phosphorous oxide according to the present invention is used as an extreme pressure agent and has compatibility (mixing stability) with the acrylic acid-based polymer in a neutralized state. , it is possible to express a certain coating film and performance during work. According to the present invention, in particular, polyphosphoric oxide is more excellent in the effect of lowering the coefficient of friction.

According to the present invention, the phosphoric acid ester is any one or more selected from the group consisting of alkyl acid phosphate, dioleyl hydrogen phosphite and polyether phosphate, and the polyphosphoric acid compound is polyphosphoric acid, pyrophosphoric acid, metaphosphoric acid or their It may be at least one selected from the group consisting of salts.

According to the present invention, when an acrylic acid-based polymer and phosphorous oxide are used together as a polymer binder, the shear force of the solid lubricant is strengthened compared to the case of using it alone, thereby lowering the friction coefficient, and easily performing even a forging operation with a large deformation rate It can be done, and the work performance is excellent.

According to the present invention, a preferred polymer binder may include an acrylic acid-based polymer and phosphorous oxide in a weight ratio of 1:5, and when included in the weight ratio, lubricity is high and dimensional accuracy is particularly excellent.

Figure 3a shows that after treatment with a surface treatment agent composition for cold forging containing an acrylic acid-based polymer and phosphorous oxide in a weight ratio of 1:10 to 4:10 as a binder, a dimension cutting process is performed (normal; Example), Figure 3b is a schematic diagram of a surface treatment composition for cold forging containing a single component of an acrylic acid-based polymer as a binder, followed by a dimensional cutting process (control group). As shown in FIG. 3 , it can be seen that sintering occurred in the dimensional cutting of the material.

Figure 4a shows that the upper end is treated with a surface treatment agent composition for cold forging containing an acrylic acid-based polymer and phosphorous oxide in a weight ratio of 1:10 to 4:10 as a binder, and then a deformation process by press pressure is performed (normal; practice) Example), Figure 4b is a schematic diagram of a process (control group) that was treated with a surface treatment agent composition for cold forging including a single component of an acrylic acid-based polymer as a binder, and then subjected to a deformation process by press pressure. As shown in FIG. 4 , in the control group, it can be seen that the deformability was reduced due to insufficient lubricity.

Figure 5a shows that after treatment with a surface treatment agent composition for cold forging containing an acrylic acid-based polymer and phosphorous oxide in a weight ratio of 1:10 to 4:10 as a binder, a deformation process by extrusion is performed (normal; Example); Figure 5b is a schematic view of a deformation process by extrusion after treatment with a surface treatment agent composition for cold forging including a single component of an acrylic acid-based polymer as a binder (control group). In the control group, there is a problem that the extrusion portion is not uniform.

According to the present invention, the pH of the polymer binder is preferably 3-5. When the pH is 7 or more, when a large deformation is applied, a seizure phenomenon may occur due to the lack of extreme pressure, and when the pH is less than 3, there is a difficulty in forming a film due to the surrounding rust prevention and low viscosity.

According to the present invention, the dispersant may be any one selected from the group consisting of a nonionic dispersant, an anionic dispersant, a cationic dispersant and an amphoteric dispersant, and may preferably be a compound composed of a phosphate and a fatty alcohol, and further preferably 2CH ₃ (CH ₂ ) ₇ CH=CH(CH ₂ ) ₈ OP(=O)(OH) ₂ or 2(CH ₃ (CH ₂ ) ₇ CH=CH(CH ₂ ) ₈ O) ₂ P( =O)OH, particularly preferably 2CH ₃ (CH ₂ ) ₇ CH=CH(CH ₂ ) ₈ OP(=O)(OH) ₂ . When the above compound is used as a dispersing agent, it is excellent in dispersibility, wettability and compatibility, and particularly excellent in film drying property.

The amount of the dispersant used may depend on the amount of pigment, and dispersibility and wettability are particularly excellent when the dispersant is included in an amount of 0.4 wt% with respect to a composition comprising 35 wt% as a total solid content. If the dispersant is less than the above range, the dispersion and wettability of the pigment are lowered, and there is a fear that the pigment may be dispersed into the atmosphere during use.

According to the present invention, the dispersant may have a pH of 2-6, preferably pH 3-5.

According to the present invention, the lubricity improving agent may be at least one selected from the group consisting of molybdenum disulfide, graphite, and wax, and preferably may be molybdenum disulfide or a mixture containing molybdenum disulfide. The mixture containing molybdenum disulfide may be a mixture containing molybdenum disulfide and graphite, molybdenum disulfide and wax, or molybdenum disulfide, graphite and wax, and the graphite may be added in an amount of 0.1 to 2 parts by weight based on 10 parts by weight of molybdenum disulfide. and 0.1 to 3 parts by weight of the wax may be added based on 10 parts by weight of molybdenum disulfide. It is preferable to be added in the above range because it can exhibit excellent performance and economy in the surface treatment process of cold forging.

The wax is not particularly limited as long as it is generally used as a surface treatment agent in the forging process, and since the temperature rise is different depending on the characteristics of cold extrusion, the wax having a suitable melting point according to the process has a characteristic that influences the melting point of the entire coating film It is preferable to select and use . According to the present invention, it may be particularly preferably a polyethylene-based aqueous type wax having a melting point of 50 to 130° C., and such wax is particularly preferable because it improves the performance of the surface treatment agent to be prepared.

In one embodiment of the present invention, in an aqueous dispersion having a solid content of 35% by weight, 15% by weight or less of molybdenum disulfide, 3% by weight or less of graphite, for example, impression graphite having an average particle size of 5 micrometers, and 4.5% by weight or less of wax as a solid content may be added, for example, molybdenum disulfide:graphite:wax may be mixed in a weight ratio of 10:2:3.

According to the present invention, the surface treatment agent may further include any one or more selected from a thickener, an antifoaming agent, and water.

According to the present invention, the thickener is used to increase the viscosity, and may be included in an amount of 0 to 1% by weight, preferably 0 to 0.3% by weight, and the antifoaming agent is 0 to 0.5% by weight, preferably 0 to 0.1% by weight. % may be used, and water may be an integer. The surface treatment agent composition prepared according to the present invention may have a viscosity of 600-800 cps, for example, by use of a thickener.

In addition, the present invention includes the steps of (1) preheating the material to be molded to 40 to 60 ℃; (2) applying and drying the surface treatment agent composition for cold forging on the surface of the preheated material; And (3) forming the material; provides a method for cold forging of a metal material comprising a.

In the present invention, step (2) may be to form a coating film to a thickness of 1 to 20 g/m2.

Advantages and features of the present invention, and methods for achieving them, will become apparent with reference to the embodiments described below in detail. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention belongs It is provided to fully inform the possessor of the scope of the invention, and the present invention is only defined by the scope of the claims.

Example 1.

A surface treatment composition for cold forging having a solid content of 35% by weight was prepared. 5 g of acrylic acid-based polymer (35% by weight of solid content in acrylic acid-based polymer; pH 3-5), 27 g of phosphate (solids content of 40% in phosphate, pH 3-5), dispersant (2CH ₃ (CH ₂ ) ₇ CH= CH(CH ₂ ) ₈ OP(=O)(OH) ₂ ) 0.45 g, molybdenum disulfide:graphite:wax in a weight ratio of 10:2:3 were mixed with 22 g of a lubricant improver, and an antifoaming agent (0.1 Less than weight %), a thickener (0-3 weight %) was added to prepare a surface treatment composition for cold forging.

Test Example 1. TEST

After shot blasting the material, it was placed in a container containing a degreasing solution prepared at 50±5° C., and the material was degreased and preheated. Next, after washing with water in a water washing tank at the same temperature, a coating film was formed on the surface of the roasting with the composition prepared in Example 1 by sedimentation or a spray method. The thickness of the coating film was adjusted to ^{0.5 to 17 g/m 2} according to the degree of forging deformation.

When the deformation rate is high or the extrusion operation is 2 to 4 times, or more ^{, a coating film was formed at 15-17 g/m 2} , and it was confirmed that the workability was good. When the deformation rate is small ^{, a coating film was formed at 0.5 g/m 2} , and it was recognized that the workability was good. Control of the thickness of the coating film was performed through viscosity control using a diluent.

As a result of checking the work, the quality of the forged product was improved and the mold was prevented from burning, and scratches did not occur on the surface of the material. Accordingly, it was expected that the mold life would be extended. In addition, since the generation of wastewater and energy consumption are small, the cost is reduced and the operation is easy, which improves the economic feasibility.

Claims (13)

A polymer binder containing an acrylic acid-based polymer and phosphorous oxide in a weight ratio of 1:10 to 4:10, and having a pH of 3 to 5;
one or more dispersants selected from the group consisting of anionic, cationic, amphoteric and nonionic dispersants; and
any one or more lubricity improvers selected from the group consisting of molybdenum disulfide, graphite, and wax;
A surface treatment composition for cold forging comprising a. According to claim 1,
The acrylic acid-based polymer is a copolymer of one or more monomers selected from the group consisting of acrylic acid, methacrylic acid, methyl methacrylic acid, maleic acid, silicone acryl, fluoroacrylic, phosphate acryl, ethylene and styrene,
Phosphoric oxide is at least one selected from the group consisting of phosphoric acid esters and polyphosphoric acid compounds, cold forging surface treatment composition. According to claim 1,
The acrylic acid-based polymer has a glass transition temperature of -10°C to 30°C, and a viscosity of an aqueous solution having a solid content of 10% by weight of 200 to 600 cps,
The phosphoric oxide has a pH of 1.5-7.5, a surface treatment composition for cold forging. According to claim 1,
A surface treatment composition for cold forging comprising an acrylic acid-based polymer and a phosphoric oxide in a weight ratio of 1:5. 3. The method of claim 2,
Phosphorous oxide is at least one selected from the group consisting of alkyl acid phosphate, dioleyl hydrogen phosphite, polyether phosphate, polyphosphoric acid, pyrophosphoric acid, metaphosphoric acid, or salts thereof, a surface treatment composition for cold forging. According to claim 1, wherein the dispersant,
2CH ₃ (CH ₂ ) ₇ CH=CH(CH ₂ ) ₈ OP(=O)(OH) ₂ or 2(CH ₃ (CH ₂ ) ₇ CH=CH(CH ₂ ) ₈ O) ₂ P(=O) OH, and the pH is 3-5, a surface treatment composition for cold forging. According to claim 1,
The lubricity improving agent, based on 10 parts by weight of molybdenum disulfide, 0.1 to 2 parts by weight of graphite, and 0.1 to 3 parts by weight of a polyethylene wax having a melting point of 50 to 130° C. are mixed, a surface treatment composition for cold forging. According to claim 1,
The surface treatment composition for cold forging further comprising any one or more selected from a thickener, an antifoaming agent, and water. According to claim 1,
A surface treatment agent composition for cold forging, comprising 20 to 35 parts by weight of phosphate, 0.1 to 1 parts by weight of a dispersant, and 15 to 30 parts by weight of a lubricity improver, and a viscosity of 100 to 800 cps based on 5 parts by weight of the acrylic acid-based polymer. According to claim 1,
5 parts by weight of an acrylic acid-based polymer having a solid content of 35% by weight; 27 parts by weight of phosphoric oxide having a solid content of 35% by weight; 0.45 parts by weight of a dispersant; and 22 wt% of a lubricity improver in which molybdenum disulfide:graphite:wax is mixed in a weight ratio of 10:2:3, and has a viscosity of 100 to 800 cps, a surface treatment composition for cold forging. 11. The method of claim 10,
The acryl-based polymer is a polyacrylic having a pH of 3-5, a glass transition temperature of -10 to 30 ° C., and the phosphorous oxide is a polyphosphoric oxide having a pH of 3-5,
The dispersant is 2CH ₃ (CH ₂ ) ₇ CH=CH(CH ₂ ) ₈ OP(=O)(OH) ₂ , a surface treatment agent composition for cold forging. (1) preheating the material to be molded to 40 to 60°C;
(2) applying and drying the surface treatment composition for cold forging according to any one of claims 1 to 11 on the surface of the preheated material; and
(3) forming the material; cold forging method of a metal material comprising a. 13. The method of claim 12,
The (2) step is to form a coating film to a thickness of 1 to 20 g/m ² , the method.

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