JP4939172B2 - Water-soluble lubricant for plastic processing, metal materials for plastic processing and metal processed products - Google Patents

Description

  The present invention relates to a water-soluble lubricant for plastic working, a metal material for plastic working, and a metal processed product, and more particularly to film properties such as lubricity, seizure resistance, and corrosion resistance without containing phosphorus in the film. The present invention relates to a water-soluble lubricant for plastic working capable of forming an excellent lubricating film, and to a metal material for plastic working and a metal processed article provided with such a lubricating film. The metal material of the present invention is, for example, machine parts such as bolts, nuts, and springs obtained by plastic working such as drawing, pressing, forging, and forging, steel cords, bead wires, and drawn wires such as PC (prestressed concrete) steel wires. It is suitably used for manufacturing metal processed products such as processed products.

  Metal materials for plastic working are subjected to various plastic processing such as drawing, wire drawing, forging, forging, etc., depending on the application. At that time, processing tools (dies, plugs, punches, etc.) and workpiece ( A high pressure is applied to the metal material), and seizure is likely to occur with slippage between them. Therefore, in order to reduce the friction on the surface of the workpiece and prevent seizure, a lubricating film is usually formed on the surface of the metal material.

  A typical example of the lubricating film is a composite film composed of a phosphate film and a soap layer (hereinafter sometimes referred to as “chemical conversion film”). This chemical conversion coating is a phosphate coating on a metal material, and then a reactive soap lubrication treatment is performed to react sodium stearate, the main component of soap, with the phosphate coating. It is obtained by forming a soap layer composed of zinc stearate (metal soap) and sodium stearate (bath soap) with good adhesion. The chemical conversion treatment film is excellent in lubricity and seizure resistance, and also has good rust resistance, so that the metal material provided with the chemical conversion treatment film is suitable for severe processing such as cold forging. Used for.

  However, when the above metal material is used and heat treatment is performed after cold wire drawing to produce a final product such as a bolt, phosphorus is diffused (immersion phosphorus) in the metal material during heat treatment, and delayed fracture occurs. There's a problem. In addition, the formation of the phosphate film requires complicated treatment liquid management and many processes, and a large amount of sludge is generated by the chemical reaction between the treatment liquid and the material to be treated (metal material). The process requires a great deal of labor and cost.

  Therefore, a method for forming a lubricating film excellent in lubricity and seizure resistance without interposing a phosphate film has been proposed (for example, Patent Documents 1 to 4).

  Patent Document 1 discloses a predetermined water-soluble inorganic salt (sulfate, borate, etc.), a solid lubricant [fatty acid and metal salt (metal soap), calcium compound, etc.], an oil component, and a surfactant. And a water-based lubricant for cold plastic working of a metal material comprising a solid lubricant and an oil component uniformly dispersed and emulsified.

  Patent Document 2 includes an alkali metal sulfate and an alkali metal borate as essential components, an alkali metal salt of a fatty acid, an alkaline earth metal salt of a fatty acid, and a solid lubricant (for example, an adduct of melamine and cyanuric acid). And a lubricant composition comprising a water-soluble thermoplastic resin is disclosed.

  Patent Document 3 discloses a silicate, a polycarboxylate (for example, a salt of a polymer of a polymerizable monomer having a carboxylic acid group and an alkali component), a water affinity polymer and / or a water affinity organic lamellar structure. Disclosed is a film forming agent comprising a body and molybdate and / or tungstate.

  In Patent Document 4, as a base treatment, an aqueous solution obtained by adding sodium stearate and calcium oxide is applied to the surface of the drawn material, and then a predetermined soap such as stearate and fluorine A method is described in which a lubricating film is formed by a wire drawing method using a powdery lubricant containing a resin and / or molybdenum disulfide and the balance being calcium hydroxide.

On the other hand, Patent Document 5 and Patent Document 6 describe oil agents for water-soluble metal plastic working. Among these, Patent Document 5 discloses a polymer compound in which, for example, a polymerized isobutylene is partially esterified and converted to a partial amine salt with ammonia as an oil agent that can improve the working environment and the like than conventional oil agents such as graphite. Yes. Patent Document 6 discloses a cold-rolled oil composition containing a specific cationic emulsifier, a nonionic polymer compound, and a higher fatty acid alcohol in a base oil such as animal and vegetable oils and fats. It describes that rolling lubricity and emulsification stability are improved.
Japanese Patent Laid-Open No. 10-8085 Japanese Patent Laid-Open No. 10-36876 JP 2002-363593 A JP 2003-49188 A Japanese Patent Laid-Open No. 10-46184 Japanese Patent Laid-Open No. 11-61167

  As described above, various methods for forming a lubricating film excellent in lubricity and seizure resistance without interposing a phosphate film have been proposed so far, but further improvement is required. ing.

  The present invention has been made in view of the above circumstances, and its purpose is to achieve lubricity and seizure resistance equivalent to or higher than those of a chemical conversion treatment film containing phosphorus, even if the film does not contain phosphorus. The object of the present invention is to provide a water-soluble lubricant for plastic working capable of forming a lubricating film excellent in corrosion resistance and a metal material for plastic working provided with such a lubricating film.

The water-soluble lubricant for plastic working of the present invention that has solved the above problems has a gist in that it contains the following components A to D in a mass ratio with respect to the total amount of A + B + C + D in the following range.
A component: 10-30% of water-soluble inorganic salt,
B component: 5-30% of organometallic salt,
C component: 10-84.5% of alkaline earth metal salt,
Component D: As a solid dispersant, a copolymer of α-olefin and maleic anhydride
Reaction with N, N-dialkylaminoalkylamine
0.5-30%

Moreover, the metal material for plastic working of the present invention that has solved the above-mentioned problems is a metal material for plastic working characterized in that a lubricating film is provided on the surface. Is contained in the following range in a mass ratio with respect to the total amount of A + B + C + D.
A component: 10-30% of water-soluble inorganic salt,
B component: 5-30% of organometallic salt,
C component: 10-84.5% of alkaline earth metal salt,
Component D: As a solid dispersant, a copolymer of α-olefin and maleic anhydride
Reaction with N, N-dialkylaminoalkylamine
0.5-30%

  The present invention also includes a metal processed product obtained by plastic processing the metal material for plastic processing.

  Since the water-soluble lubricant for plastic working according to the present invention is configured as described above, if the lubricant is used, the lubricant film has excellent adhesion to a metal material, and also has good lubricity, seizure resistance, and corrosion resistance. Is obtained. Therefore, the lubricant of the present invention is particularly suitably used as a material for strong processing such as cold forging and strong wire drawing. Further, since the lubricating film obtained in this way does not contain phosphorus, there is no occurrence of delayed fracture due to phosphorus immersion. Moreover, since the lubricating film is easily formed by simply bringing a water-based solvent containing the lubricant of the present invention into contact with a metal material (immersion, spray coating, etc.) for a short time, it is excellent in productivity.

  In order to provide a metal material for plastic working having a non-phosphorus-based lubricating film having a lubricity and seizure resistance equal to or higher than those of a chemical conversion coating and having excellent corrosion resistance, From the viewpoint of improving the adhesion between the material and the lubricating film, we have intensively studied. As a result, a water-soluble inorganic salt (component A), an organic metal salt (component B), and an alkaline earth metal salt (component C), as a solid dispersant, a copolymer of α-olefin and maleic anhydride, , N, N-dialkylaminoalkylamine containing a reaction product (component D), and by using a water-soluble lubricant for plastic working in which these ratios are appropriately controlled, the intended purpose is achieved. As a result, the present invention has been completed.

  As described above, the lubricant according to the present invention is characterized in that the solid dispersion agent D is mixed with the components A, B, and C. As will be described in detail below, the component D has various actions, and as a main action, in addition to a dispersing action that can disperse the lubricant in the aqueous solvent, a film forming action, a wetting improving action, etc. Can be mentioned. According to the inventor's experiment, (a) the above-described action by the D component is effectively exhibited by mixing a predetermined amount in the components A to C, and (a) the components A to D are If the lubricant containing is used, the adhesiveness to the metal material is further improved as compared with the case where the lubricant containing only the components A to C and not containing the D component is used. It has become clear that (see Examples below).

  The D component that characterizes the present invention is also disclosed in Patent Document 6 described above. However, Patent Document 6 relates to the technology of water-soluble metal plastic working oil (emulsion rolling oil), and relates to the technology of film lubricant in that D component is used as a cationic emulsifier. Is different from the present invention in which is added as a solid dispersant in the technical field and the purpose (form of use) of the D component. In Patent Document 6, a D component is blended mainly for the purpose of preventing an increase in the amount of plate-out (amount of rolling oil adhering to the surface of the material to be rolled) and a decrease in emulsion stability when a nonionic emulsifier is used. However, the constituent requirement of the present invention that the component D is added to the components A to C is not disclosed. Of course, Patent Document 6 does not disclose a technical idea of blending the component D into the components A to C for the purpose of improving the lubricity and seizure resistance of the coating lubricant.

  Further, Patent Document 5 discloses an olefin-maleic acid polymer, but the D component used in the present invention is not substantially disclosed. Furthermore, Patent Document 5 does not disclose the constituent requirement of the present invention in which the component D is added to the components A to C, and does not disclose the technical idea of the present invention described above.

  Hereinafter, the components (A component to D component) of the water-soluble lubricant for plastic working according to the present invention will be described in detail. In the present specification, “%” means mass%.

(1) A component: 10-30% of water-soluble inorganic salt
The water-soluble inorganic salt (component A) is a useful component as a film forming agent (film forming agent) for obtaining a lubricating film having excellent adhesion to a metal material. The lubricant of the present invention contains an alkaline earth metal salt (C component) as a film-forming agent, and the above-mentioned A component is positioned as a film-forming auxiliary agent in relation to the C component. Since the A component easily follows the deformation of the metal material during plastic working, the addition of the A component suppresses seizure between the plastic working tool and the metal material, and improves carrier properties and lubricity.

  The water-soluble inorganic salt used in the present invention is not particularly limited as long as it is generally used as a carrier for plastic working lubricants. For example, borate, silicate, molybdate and the like are representatively exemplified. . A preferred water-soluble inorganic salt is borate. These may be used alone or in combination of two or more.

In the above borate, examples of boric acid include orthoboric acid, diboric acid, metaboric acid, tetraboric acid, pentaboric acid, and octaboric acid. Examples of the borate include metal salts such as alkali metal salts (Li salt, Na salt, K salt, etc.), alkaline earth metal salts (Mg salt, Ca salt, etc.), and alkanolamine salts (monoethanolamine, diethanolamine, Also included are nitrogen-containing salts such as ammonium salts). Preferable borates are metaborate, tetraborate, etc., for example, sodium metaborate, sodium tetraborate (Na ₂ B ₄ O ₅ (OH) ₄ · 8H ₂ O called borax, borax, etc.), tetraborate Typical examples include potassium and ammonium tetraborate.

  The borate may be used alone or in combination of two or more.

As the silicate, in addition to a salt represented by the formula xM ^I ₂ O · ySiO ₂ (where x and y represent natural numbers and M ^I represents an alkali metal), The thing which a part or all replaced by the alkaline component etc. are mentioned. Silicic acid includes orthosilicic acid (H ₄ SiO ₄ ), metasilicic acid (H ₂ SiO ₃ ), metadisilicic acid (H ₂ Si ₂ O ₅ ), metatrisilicic acid (H ₄ Si ₃ O ₈ ), and meta Silicic acid (H ₆ Si ₄ O ₁₁ ) and the like are also included. Examples of the alkali component include alkali metals (Li, Na, K, etc.), alkaline earth metals (Mg, Ca, etc.) and the like. Preferred alkali components are Na, K, Ca and the like. Preferred silicates include alkali metal silicates (such as potassium silicate and sodium silicate), alkali metal metasilicates (such as sodium metasilicate), alkaline earth metal silicates (such as calcium silicate), water glass [eg, formula Na ₂ And a compound represented by O.nSiO ₂ (wherein n represents an integer of 2 to 4).

  Silicates may be used alone or in combination of two or more.

  Molybdate is also useful as a rust inhibitor. In the molybdate, the molybdic acid includes orthomolybdic acid, metamolybdic acid, paramolybdic acid, and the like. Examples of molybdates include alkali metal salts (Li salt, Na salt, K salt, etc.), alkaline earth metal salts (Mg salt, Ca salt, etc.), amine salts (monoethanolamine, diethanolamine, triethanolamine, etc.). And the like. A preferred molybdate is sodium metamolybdate.

  The ratio of the A component to the total amount of the A to D components is 10 to 30%. When the ratio of the component A is less than 10%, the action as a film-forming agent is not effectively exhibited. On the other hand, when it exceeds 30%, the friction coefficient increases, the resistance during processing increases, and conversely, the film is formed. It will come off. The ratio of the component A is preferably in the range of 15 to 25%, more preferably in the range of 20 to 23%.

(2) Component B: 5-30% of organometallic salt
The organometallic salt (component B) is a component useful as a lubricant, and this improves the lubricity.

  The organometallic salt used in the present invention is not particularly limited as long as it is generally used as a lubricant for plastic working lubricants, and representative examples thereof include salts of fatty acids and metals. “Fatty acid” includes both saturated and unsaturated fatty acids. Examples of saturated fatty acids include lower saturated fatty acids such as acetic acid (C = 2), propionic acid (C = 3), butyric acid (C = 4), and valeric acid (C = 5); palmitic acid (C = 16), Carbon such as stearic acid (C = 18), arachidic acid (C = 20), pehenic acid (C = 22), lignoceric acid (C = 24), serotic acid (C = 26), montanic acid (C = 28) The higher saturated fatty acid of several 16 or more is mentioned. Also included is coconut oil fatty acid. Preferred saturated fatty acids are higher saturated fatty acids, and palmitic acid and stearic acid are more preferred. Examples of the unsaturated fatty acid include higher unsaturated fatty acids having 16 or more carbon atoms, such as palmitooleic acid (C = 16), oleic acid (C = 18), paxcellic acid (C = 18), linoleic acid ( C = 18), linolenic acid (C = 18), arachidonic acid (C = 20), nervonic acid (C = 22) and the like. Preferred unsaturated fatty acids are arachidonic acid and oleic acid. Examples of the “metal salt” in the salt of fatty acid and metal include, for example, alkali metal salts (Li salt, Na salt, K salt, etc.), alkaline earth metal salts (Mg salt, Ca salt, Sr salt, Ba salt). Etc.), aluminum salts, transition metal salts (Cu salt, Zn salt, Ag salt, Ta salt, Ni salt, Co salt, Pb salt, Mn salt, etc.). These may be used alone or in combination of two or more.

  The ratio of the B component in the total amount of the A to D components is 5 to 30%. When the ratio of the B component is less than 5%, the friction coefficient increases and the water repellency decreases. On the other hand, when the ratio of the B component exceeds 30%, the adhesion of the film is lowered. The ratio of the component B is preferably in the range of 10 to 25%, and more preferably in the range of 19 to 22%.

(3) C component: 10-84.5% of alkaline earth metal salt
The alkaline earth metal salt (component C) is a useful component as a film forming agent and a dispersing agent. The addition of component C not only enhances the film-forming property of the film, but also improves the lubricity and seizure resistance. This is because the processing tool such as a die or a die and a metal material (working material) It is considered that the C component does not dissolve even when the contact portion (contact between metals) rises to about 150 to 400 ° C., and has a role of preventing contact between the processing tool and the metal material.

  The alkaline earth metal salt used in the present invention is not particularly limited as long as it is generally used as a lubricant and a film-forming agent for plastic working lubricants. For example, Ca salts such as calcium hydroxide and calcium sulfate A Mg salt such as magnesium hydroxide and magnesium sulfate, and a Ba salt such as barium hydroxide. A preferred alkaline earth metal salt is a Ca salt, and examples thereof include calcium hydroxide. These may be used alone or in combination of two or more.

  The ratio of the C component to the total amount of the A to D components is 10 to 84.5%. When the C component ratio is less than 10%, it is difficult to ensure a predetermined film thickness. On the other hand, when the C component ratio exceeds 84.5%, the adhesion of the film is lowered. The proportion of component C is preferably in the range of 40 to 60%, and more preferably in the range of 45 to 50%.

(4) Component D: 0.5 to 30% of a reaction product of a copolymer of α-olefin and maleic anhydride and N, N-dialkylaminoalkylamine as a solid dispersant.
The component D is a component that characterizes the present invention, and is useful as a dispersant, a film-forming agent, a wetting improver, and the like.

  Specifically, the D component is a component that mainly contributes to further improving the dispersibility of the C component such as calcium hydroxide and further improving the adhesion to the metal material. As shown in the examples described later, the lubricating film containing all of the components A to D is further improved in adhesion with a metal material and improved in seizure resistance as compared with a lubricating film not containing the D component. The

  In the present invention, the reason for paying attention to the D component is as follows.

  Conventionally, for example, in a lubricating film mainly composed of an A component such as borate, the hardness of the film is high, so that it is difficult to follow deformation during plastic processing of a metal material. Burn-in was observed. In particular, when a high degree of plastic working is required, seizure is noticeable and has become a problem. Therefore, in order to search for a component that can easily follow deformation during plastic processing and has excellent seizure resistance, both inorganic and organic components were examined. As a result, when inorganic components are used, cracks are likely to occur when the degree of plastic processing is increased or the film thickness is increased, whereas when organic components are used, there is no such problem. Therefore, further investigation was conducted focusing on organic components. As a result, it was found that if the D component was used, the intended purpose was achieved, and the D component was adopted.

  The component D has an appropriate viscosity when dissolved in an aqueous solvent and has a thermally stable polymer skeleton, and therefore has excellent adhesion to a metal material. When the D component is used as a solid lubricant as in the present invention, the seizure resistance, film adhesion, and the like are improved as compared to the case where the D component is used as an emulsion as in Patent Document 6 described above.

  The component D is a reaction product of a copolymer of α-olefin and maleic anhydride and N, N-dialkylaminoalkylamine, and examples thereof include the above adducts. The number average molecular weight of component D is in the range of about 10,000 to 50,000 and the carbon number is in the range of about 22 to 50, the preferred number average molecular weight is 12,000 to 35,000, and the preferred carbon number is 20 to 30. Degree. The number average molecular weight of the D component is determined by polystyrene conversion using a gel permeation chromatography (GPC) method.

  As the α-olefin constituting the component D, a linear or branched one having about 6 to 35 carbon atoms is used. Preferably, it is a linear or branched α-olefin having about 8 to 28 carbon atoms, such as 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene.

Further, N, N-dialkylaminoalkylamine is a compound represented by the following formula (1), wherein n is an integer of 1 to 10, R ¹ or R ² is the same or different and has 1 carbon atom. -18 linear or branched alkyl. Preferably, n is an integer of 1 to 4, R ¹ or R ² is the same or different and is a linear or branched alkyl group having 1 to 3 carbon atoms. Preferred N, N-dialkylaminoalkylamines are, for example, dimethylaminoethylamine, dimethylaminopropylamine, diethylaminohexylamine, diethylaminopropylamine and the like.

  The ratio of the D component to the total amount of the A to D components is 0.5 to 30%. When the ratio of the D component is less than 0.5%, the film forming action is reduced, and it becomes difficult to secure a predetermined film thickness. On the other hand, when the ratio of the D component exceeds 30%, the friction coefficient is high. Thus, the resistance during processing increases, and the film peels off. The proportion of component D is preferably in the range of 5 to 20%, more preferably in the range of 15 to 18%.

  D component can be manufactured as follows, for example. First, a polymerized olefin, which is a copolymer of an α-olefin and maleic anhydride, is dissolved in a nonpolar solvent such as benzene, toluene, or xylene. Next, N, N-dialkylaminoalkylamine is added and heated to amidate. Thereafter, NaOH is added dropwise to form a partial sodium salt, and the solvent used is distilled off.

  The lubricant of the present invention basically contains the above components A to D as active ingredients, but contains other components usually contained in the lubricant as long as the effects of the present invention are not impaired. These may also be included within the scope of the present invention. In addition, the lubricant of the present invention includes a mixture (water-based lubricant) of the above-mentioned active ingredients (components A to D, and further, if necessary, other components) and an aqueous solvent (particularly water). Are also included. This is because, as will be described later, the lubricating film is formed by contacting a metal material with a mixed liquid (aqueous lubricant) obtained by mixing the above-mentioned active ingredient with an aqueous solvent. The water-based lubricant is suitably used for producing a lubricating film.

  Examples of other components that can be included in the lubricant of the present invention include the following components.

(Surfactant)
The surfactant is a component added as necessary in the process of forming the lubricating film. As will be described in detail later, the lubricating film is formed by immersing a metal material in an aqueous solution containing the above-described components (immersion method), but the film adhesion hardly dissolves in water such as stearate. When using a property improving component, it is preferable to add a surfactant to improve dispersibility (coating property). Further, since the surfactant is adsorbed on the surface of the metal material and also has a rust prevention action, the corrosion resistance is also improved.

  The content of the surfactant contained in the lubricant varies depending on the components constituting the lubricant and the type of the surfactant used, but is generally preferably in the range of 0.1 to 1%. . If the surfactant content is less than 0.1%, the corrosion resistance and dispersibility are insufficient. On the other hand, adding more than 1% only saturates these functions and increases the cost.

  Examples of the surfactant used in the present invention include various cationic, anionic and nonionic surfactants. Examples of the cationic surfactant include quaternary ammonium salts, alkylpyridinium salts, and benzalkonium chloride. Examples of the anionic surfactant include sodium alkylbenzene sulfonate and dodecylbenzene sulfonic acid. Examples of nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkylphenols, polyoxyethylene alkyl esters, polyoxyethylene sorbitan alkyl esters, and the like. Can be mentioned.

(Solid lubricant)
In order to further improve the lubricity by reducing the friction coefficient of the lubricating film, the lubricant may contain a solid lubricant. The kind of solid lubricant is not particularly limited, and examples thereof include paraffin wax, molybdenum disulfide, graphite, boron nitride, mica, graphite fluoride, polytetrafluoroethylene, and polyethylene. These may be used alone or in combination of two or more. It is preferable that the amount of the solid lubricant contained in the lubricant is approximately in the range of 0.1 to 5%.

(anti-rust)
The lubricating film may contain a rust inhibitor for the purpose of further improving the corrosion resistance. The type of the rust preventive is not particularly limited, and those usually contained in the lubricating film can be used. Examples thereof include alkenyl succinic acid amine salt, vanadate, polyacrylic acid, silica, and benzotriazole. . The amount of the rust inhibitor contained in the lubricant is preferably within a range of about 0.1 to 5%.

(Sulfate)
Sulfate contributes to improvement of carrier properties and film strength, and is a useful component for reducing seizure between the metal material and the processing tool. In particular, sulfate is extremely useful when a film is formed on a metal material that is subjected to plastic working with a high degree of deformation. Examples of the sulfate include alkali metal sulfate and alkaline earth metal sulfate. These may be used alone or in combination of two or more. Preferred sulfates are alkali metal sulfates (eg, sodium sulfate, potassium sulfate, etc.). The amount of sulfate contained in the lubricant is preferably in the range of about 5 to 10%.

  Next, a method for forming a lubricating film using the lubricant of the present invention will be described.

  The lubricating coating is obtained by bringing a mixed liquid (preparation liquid, treatment liquid) of the above-described active ingredient and aqueous solvent into contact with a metal material, and drying as necessary (dry method). The contact method is not particularly limited, and a method usually used for obtaining a lubricating film using a plastic working lubricant can be appropriately employed. For example, a method of immersing a metal material in the above mixed solution and drying, a method of applying the above mixed solution to the metal material (application by spraying, etc.) and the like can be mentioned.

  Here, the dry method used in the present invention will be described. Methods for forming a lubricating film using an aqueous lubricant are roughly classified into a wet method and a dry method. The wet method is applied when a lubricant based on mineral oil, animal or vegetable oil or the like is used, and is a method of forming a liquid film by directly pouring the lubricant onto a metal material (processed material). . This method is mainly used for obtaining a material with a relatively low degree of processing. On the other hand, the dry method is a method of forming a solid film by evaporating moisture in a drying step as necessary after immersing a metal material in a lubricant. The method of the present invention is different from the technique of Patent Document 6 that employs the former wet method in that the latter dry method is employed.

  According to the method of the present invention, problems caused by the dry method such as adhesion unevenness can be avoided. That is, in the dry method using a water-based lubricant, a film is usually formed by immersing a large amount of a metal material at a time and then forcibly drying it. In that case, adhesion due to partial contact of the metal material There are many problems such as unevenness, and seizure is likely to occur during the drawing process. According to the present invention, since the lubricant composed of the components A to C is combined with the component D, the adhesion with the metal material is remarkably improved, and the seizure reduction due to the adhesion unevenness described above. Such problems are solved.

  Below, the method to form a lubricating film through the immersion process which is a typical example of a dry process is demonstrated in detail.

  First, the liquid mixture which mixed the AD component mentioned above and also the other component with the aqueous solvent as needed is prepared.

  Examples of the aqueous solvent used in the present invention include water and a mixture of water and a water-soluble solvent. Examples of the water-soluble solvent include alcohols such as methanol, ethanol and ethylene glycol; ketones such as acetone; ethers such as tetrahydrofuran and ethylene glycol dimethyl ether; and nitriles such as acetonitrile. A preferred aqueous solvent is water.

  The concentration of the lubricant when mixed with an aqueous solvent is generally preferably 5% or more, more preferably 7% or more, and even more preferably 10% or more. If the concentration of the lubricant is too thin, the formation of the film may be non-uniform. On the other hand, the upper limit of the concentration of the lubricant is not particularly limited as long as the lubricant can be dissolved in the aqueous solvent, but is generally preferably 70% or less, more preferably 60% or less. However, if the concentration of the lubricant is too high, the adhesion of the film may be lowered. Therefore, in view of the above viewpoint, the concentration of the lubricant is generally 50% or less, more preferably 45. % Or less.

  Next, the metal material is immersed in the mixed solution. Although the specific immersion conditions are not particularly limited, it is preferable to carry out at a temperature of about 30 to 80 ° C. (more preferably 40 to 70 ° C.) for about 5 seconds (more preferably 10 seconds or more). If the immersion temperature is below the above range, it is necessary to strictly control the immersion temperature in a high temperature environment such as summer. On the other hand, if the immersion temperature exceeds the above range, evaporation of the liquid mixture increases and lubrication occurs. The concentration of the agent tends to fluctuate. Moreover, when immersion time is less than the said range, adhesiveness will fall. In addition, although the upper limit of immersion time is not specifically limited, Even if it soaks over about 15 minutes, the adhesive improvement effect is not acquired.

  After the immersion, it may be dried as necessary, whereby a desired lubricating film is obtained.

  In the above description, the step of bringing the metal material into contact with the mixture of the lubricant and the aqueous liquid agent (film forming step) has been described in detail, but for the purpose of cleaning the surface of the metal material in the previous step of the film forming step. A cleaning step may be performed. Examples of the cleaning treatment include descaling treatment and degreasing treatment. A conventional method can be applied to the descaling treatment, and examples thereof include a mechanical descaling method (blasting method such as shot blasting and bending) and a chemical descaling method (pickling and the like). A preferred descaling method is a mechanical descaling method. The mechanical descaling method can be descaled not by batch processing but by inline processing, and is therefore suitable for the present invention in which a film is physically formed in a short time.

  The lubricating film thus obtained contains components according to the composition of the lubricant used. Specifically, the above-mentioned components A to D are mass ratios with respect to the total amount of A + B + C + D, A component: 10 to 30%, B component: 5 to 30%, C component: 10 to 84.5%, D component: Contains 0.5-30%. When the active ingredient contained in the lubricant contains other components than the above-described components A to D, the lubricant film includes those according to the concentration of the other components contained in the lubricant. .

The adhesion amount of the lubricating film is preferably in the range of ^{2 to} 40 g / m ² or more. If the adhesion amount is less than 2 g / m ² , it is difficult to perform continuous wire drawing much. On the other hand, even if the adhesion amount exceeds 40 g / m ² , the above-described action by the lubricating film is saturated, resulting in an increase in cost. Because it is just useless economically. The adhesion amount of the lubricating film is more preferably in the range of about 4 g / m ^{2 to} 20 g / m ² .

  The above lubricating film exhibits excellent characteristics even when directly formed on a metal material without interposing an underlayer (see the examples described later), but further improves the adhesion to the metal material. For the purpose of further improving the above characteristics, a general-purpose underlayer (silica-containing layer) may be interposed.

  Moreover, on the said lubricating film, the other film | membrane containing a silica etc. may be coat | covered in order to provide rust prevention property. These other films may be formed as a single layer, or two or more layers may be laminated.

  The metal material of the present invention has the above lubricating film on the surface and is used for plastic working (details will be described later).

  The composition of the metal material used in the present invention is not particularly limited as long as it is used for plastic working. For example, various metal materials such as steel materials (iron, stainless steel, chromium steel, molybdenum steel, titanium steel, etc.) and non-ferrous metal materials (aluminum material, titanium material, copper material, etc.) are used. A preferable metal material is a steel material.

  The form of the metal material is not particularly limited as long as it is a metal material for plastic working. For example, various metals such as a wire material or a rod material, a cutting material (blank material) obtained by cutting the wire material or the rod material, and a steel plate. The material can be used. A preferable metal material is a wire, a bar, a blank, or the like. Examples of the wire or bar include a wire or bar for producing bolts, nuts, springs, PC (prestressed concrete) steel, steel cords, bead wires, and the like. The blank material includes a blank material for manufacturing a front or rear extruded part.

  The present invention also includes a metal processed product obtained by plastic processing of a metal material provided with the above lubricating film. Examples of the metal processed product include bolts, nuts, springs, PC steel, steel cords, bead wires, front or rear extruded parts, and rolled steel sheets.

  In this specification, “plastic working” includes drawing or wire drawing, forging or forging, rolling, and the like. Forging or forging includes, for example, cold forging and warm forging.

  The type of plastic working can be appropriately selected according to the use of the metal material. Depending on the use of the metal material, a plurality of plastic workings may be performed. For example, when manufacturing bolts and nuts, forging is performed after drawing. In the case of manufacturing a forward or backward extruded part, a wire or bar is drawn, cut, and then forged. When manufacturing steel cords, bead wires, etc., wire drawing is performed in a plurality of stages such as primary wire drawing and secondary wire drawing. When performing a plurality of plastic workings, the above-described lubricating film forming step may be performed before at least one plastic working, or the above-described lubricating film forming step may be performed before each plastic working. .

The coating amount on the surface of the metal workpiece may be similar to the coating amount on the metal material surface described above, but is usually smaller than the adhesion amount on the metal material surface, for example, preferably 2 g / m ² or more. 40 g / m ² or less (more preferably 3 g / m ² or more and 30 g / m ² or less, more preferably 4 g / m ² or more and 20 g / m ² or less).

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited by the following examples, and is implemented with appropriate modifications within a range that can meet the purpose described above and below. Any of these may be included in the technical scope of the present invention.

Example 1
(Production of test materials)
As a metal material, a hot-rolled wire (diameter 10.3 mm) obtained by hot-rolling steel type SCM440 is spheroidized and annealed at 760 ° C., and then pickled (20% sulfuric acid, in a pickled solution at 75 ° C.) For 13 minutes, and then dipped in 15% hydrochloric acid and 30 ° C. pickling solution for 13.5 minutes), descaled and washed with water.

  On the other hand, as the coating solution, No. A mixed solution in which 1 to 10 lubricants were diluted 5 times with water was prepared.

In Table 1, the details of the components A to E are as follows.
A: Sodium metaborate B: Zinc stearate C: Calcium hydroxide D1: 1-dodecene / maleic anhydride copolymer (number average molecular weight 28,000) dimethylaminopropylamine adduct / partial sodium salt D2: 1- Diethylaminohexylamine adduct / partial sodium salt of eicosene / maleic anhydride copolymer (number average molecular weight 16,000) E1: Sodium sulfonate as surfactant E2: Dodecenyl succinic acid amine salt as rust inhibitor

  The structure of said D1 component and D2 component is as showing below, and these were manufactured as follows.

  First, a polymaleinated olefin which is a copolymer of an α-olefin (1-dodecene in D1 and 1-eicocene in D2) and maleic anhydride was dissolved in a nonpolar solvent such as benzene, toluene, xylene and the like. Next, N, N-dialkylaminoalkylamine was added and reacted at about 80 to 130 ° C. for 5 hours to amidate, then 40% NaOH (NaOH 1 mol) was added dropwise to form a partial sodium salt, and the solvent was distilled off. Left.

  The above-mentioned metal material was immersed in the above-mentioned coating solution for 10 seconds and dried to obtain No. 1 having various lubricating coatings shown in Table 2. 1 to 10 specimens were obtained.

  Furthermore, for reference, No. 1 provided with a chemical conversion treatment film comprising zinc phosphate and a soap layer. Eleven specimens (diameter 10.3 mm) were produced. Specifically, the metal material obtained in the same manner as above was immersed for 10 minutes in an aqueous solution (80 ° C.) containing 150 g / L of a zinc phosphate chemical conversion treatment agent (“Palbond 421X” manufactured by Nihon Parkerizing Co., Ltd.). Then, it was washed with water to form a zinc phosphate film. Next, soap treatment was performed by dipping in a treatment liquid (80 ° C.) containing 70 g / L of a soap lubricant (“Palube 235” manufactured by Nippon Parkerizing Co., Ltd.) for 5 minutes.

  Using the test material thus obtained, the composition and content of the lubricating film were measured by the method described above, and the following test was performed.

(Bowden test)
The Bowden test is a test performed to evaluate the seizure resistance and film adhesion of a lubricating film. The outline of the Bowden test will be described with reference to FIG. Here, a Bauden testing machine manufactured by Shinko Machine was used.

  In the Bowden test, as shown in the figure, when the reciprocating sliding test was performed in a state where the longitudinal direction of the test piece was the sliding direction and a load was applied by a steel ball, the friction coefficient μ was increased to 0.10. The number of times of reciprocating sliding [twist (strain)] is measured. The larger the number of sliding times, the better the seizure resistance and film adhesion.

Details of the test conditions are as follows.
Shape of test piece: 0.8 mm x 80 mm x 100 mm
Specimen temperature: 200 ° C
Load: 3kgf
Sliding speed: 3.66 mm / sec
Steel ball: SUJ-2, diameter φ3 / 16 inch Sliding length: 50 mm

  In this example, those having a reciprocating sliding frequency n of 300 or more were evaluated as “excellent in seizure resistance and film adhesion”.

(Ball thread test)
The ball penetration test is a test performed to evaluate the seizure resistance and film strength of the lubricating film. The aforementioned Bauden test is also consistent with the ball-through test in that it evaluates the seizure resistance of the film, but the Bauden test is mainly in terms of evaluating the seizure resistance in relation to the film adhesion. Strictly different from the ball penetration test, which mainly evaluates the seizure resistance in relation to the film strength. In this example, in order to evaluate the seizure resistance, both of these tests were performed, and a good result was evaluated as “excellent in seizure resistance” for any test result.

  The outline of the ball threading test will be described with reference to FIG. Here, a 110T crank press tester manufactured by Komatsu was used.

In the ball passing test, as shown in FIG. 2, a ball 5 having a diameter larger than the inner diameter of the test material 3 was passed through the test material 3 (outer diameter 20 mm) installed on the die 4 with a punch 2. In some cases, the seizure resistance is evaluated based on the maximum area reduction ratio at which seizure does not occur. As shown in Table 3, the area reduction rate is changed by a combination of the diameter of the ball and the inner diameter of the test material. The larger the area reduction, the better the seizure resistance. The area reduction rate is represented by the rate of decrease in the cross-sectional area of the specimen before and after the test, and is specifically calculated based on the following equation.
Area reduction ratio (%) = [(A−B) / (A)] × 100
A: Cross-sectional area of the test material before the test B: Cross-sectional area of the test material after the test

  Here, those having an area reduction rate of 7% or more were evaluated as “excellent in seizure resistance and film strength”.

  These results are also shown in Table 2.

  FIG. 3 shows the results of the Bowden test. In detail, in FIGS. 1-No. 11 shows the relationship between the number of sliding times and the friction coefficient.

  From Table 2, it can be considered as follows.

  No. Nos. 1 to 6 are examples in which a lubricant film was formed using a lubricant satisfying the requirements of the present invention, and the results of the Bowden test and the ball-through test were both good. Compared to 11, it has excellent seizure resistance.

Specifically, no. No. 1, no. 2-No. No. 6 differs in the following points, but all satisfy the requirements of the present invention, so that desired characteristics are exhibited.
No. 2: No. 1, an example in which only the type of the D component is changed. 3: No. In Example 1, the amount of the D component was reduced to 3/5. 4: No. In Example 1, the amount of the D component was reduced to 1/5. 5: No. 1, the amount of components A to D is reduced to ½
(The ratio of components A to D does not change)
No. 6: No. 2, the amount of components A to D is reduced to ½
(The ratio of components A to D does not change)

  On the other hand, the following examples that do not satisfy any of the requirements of the present invention have the following problems.

  No. No. 7 is an example that contains only the A to C components and does not contain the D component that characterizes the present invention. Compared to 1, the results of the ball-through test were the same (both area reduction was 8%), but the results of the Bowden test were significantly reduced.

  No. No. 8 does not contain a D component, and no. No. 1 in which the amount of component A is reduced to ½. Compared to 1, the results of the ball-through test were the same (both area reduction was 8%), but the results of the Bowden test were significantly reduced.

  No. No. 9 is an example not containing the A component and the D component, and No. 9 containing the A component and the D component. Compared to 1, the results of both the ball-through test and the Bowden test were significantly reduced.

No. No. 10 does not contain the A component and the D component, and The amount of each of B, C, E1, and E2 of No. 1 was increased by 1.5 times, and the coating amount was No. 1. (No. 10 is 7.1 g / m ² , No. 1 is 8.2 g / m ² ). Compared to 1, the results of both the ball-through test and the Bowden test were significantly reduced.

  From these results, in order to obtain a lubricating film with excellent seizure resistance and improved film adhesion and strength, the components A to D were included, and the ratio thereof was controlled within the range specified in the present invention. The use of lubricant was confirmed to be important.

  It should be noted that the excellent effect of the present invention is caused by appropriately controlling the components constituting the lubricant as described above, and is not based on the adhesion amount of the lubricant film. Consider.

For example, no. 1 (containing components A to D) and No. 1 When comparing 10 (only B and C components, no A and D components), the coating amounts of both films are generally 8.2 g / m ² (No. 1) and 7.1 g / m ² (No. 10). In this example, the ratio of the B component / C component is also the same. No. 1 The film properties of 10 are significantly reduced.

Similarly, no. 5 (containing components A to D) and When comparing No. 9 (only B and C components, no A and D components), the coating amounts of both films are generally 2.8 g / m ² (No. 5) and 3.1 g / m ² (No. 9). In this example, the ratio of the B component / C component is also the same. No. 5 The film characteristics of No. 9 are remarkably deteriorated.

  From the above, it was proved that the excellent effect of the present invention is based on appropriately controlling the components constituting the lubricant as described above.

Example 2
In this example, the No. in Table 2 described above was used. 1 (example of the present invention), No. 1 10 (Comparative Example) and 11 (conventional example) was used to evaluate the lubricity and corrosion resistance after wire drawing in sequence as follows.

  Using the test material (φ10.3 mm) obtained by the method of Example 1, φ9.5 mm (1 pass) → φ8.3 mm (2 passes) → φ7.45 mm (3 passes) → φ6.3 mm (4 passes) ) → φ5.6 mm (5 passes) → φ4.9 mm (6 passes) → φ4.2 mm (7 passes) → φ3.6 mm (8 passes) → φ3.2 mm (9 passes) → φ2.8 mm (10 passes) → Drawing was repeated in the order of φ2.5 mm (11 passes) → φ2.2 mm (12 passes) → φ1.96 mm (13 passes). Specifically, a single pot wire drawing machine was used and the wire drawing speed was adjusted to 50 m / min.

(Evaluation of lubricity)
The wire drawing load (pull-out load) of each wire drawing material when wire drawing was performed as described above was measured, and the surface state (surface skin) was observed. Specifically, repeated tests were performed at the area reduction ratios shown in Table 4, and the wire drawing load was measured by load measurement using a load cell. Note that the wire drawing was completed when seizure occurred on the surface.

  Here, a wire drawing load of 2 kN or less, and a wire that could be drawn for 10 passes or more without causing seizure on the surface was evaluated as “excellent in lubricity”.

(Evaluation of corrosion resistance)
Corrosion resistance was determined by leaving the specimens after the coating treatment in a constant temperature and humidity tester (Tabaie spec spec PL-3SP) at a temperature of 40 ° C. and a humidity of 90% for 2 weeks, and then the surface of the side surface of the wire (32.3 cm ^2). ), The area ratio of rust generated was visually observed and evaluated.

  Here, the case where the area ratio of rust was 0% was evaluated as “excellent in corrosion resistance”.

  Table 4 shows the measurement results of the wire drawing load, and Table 5 shows the results of the corrosion resistance.

  No. in Table 2 When 1 (example of the present invention) was used, as shown in Table 4, no seizure was observed even when the wire was drawn up to φ1.96 mm (13 passes), and the wire drawing load at each wire drawing was small. The area ratio of rust is 0%. 11 (corresponding to 0% rust area ratio) and excellent corrosion resistance.

  On the other hand, No. 10 (Comparative Example) and When 11 (conventional example) was used, as shown in Table 4, in each case, seizure occurred at φ2.8 mm. No. 10 is No. Compared to 1, the wire drawing load at the time of each wire drawing was increased, and the area ratio of rust was 90%, and the corrosion resistance was remarkably reduced.

FIG. 1 is a schematic diagram showing an outline of the Bowden test used in this example. FIG. 2 is a schematic diagram showing an outline of a ball threading test used in this example. 3A shows No. 1 of Example 1. FIG. FIG. 3 is a diagram showing the results of a Bowden test in FIG. 3B shows No. 1 of Example 1. 2 is a diagram showing the results of a Bowden test in FIG. 3C shows No. 1 of Example 1. FIG. 3 is a diagram showing the results of a Bowden test in FIG. 3D shows No. 1 of Example 1. FIG. FIG. 4 is a diagram showing the results of a Bowden test in FIG. 3E shows No. 1 of Example 1. 5 is a diagram showing the results of a Bowden test in FIG. 3F shows No. 1 of Example 1. 6 is a diagram showing the results of a Bowden test in FIG. 3G shows No. 1 of Example 1. 7 is a diagram showing the results of a Bowden test in FIG. FIG. FIG. 8 is a diagram showing the results of a Bowden test in FIG. 3I shows No. 1 of Example 1. 9 is a diagram showing the results of a Bowden test in FIG. 3J shows No. 1 of Example 1. 10 is a diagram showing the results of a Bowden test in FIG. 3K shows No. 1 of Example 1. 11 is a diagram showing the results of a Bowden test in No. 11.

Explanation of symbols

1 Load Cell 2 Punch 3 Test Material 4 Die 5 Ball

Claims (3)

A water-soluble lubricant for cold plastic working, comprising the following components A to D in a mass ratio based on the total amount of A + B + C + D in the following range.
A component: 10-30% of at least one selected from the group consisting of borate, silicate, and molybdate ,
B component: 5-30% of salt of fatty acid and metal ,
Component C: 10-84.5% of at least one selected from the group consisting of calcium hydroxide, magnesium hydroxide, and barium hydroxide ,
Component D: As a solid dispersant, the number average molecular weight is 10,000 to 50,000,
Copolymer of α-olefin and maleic anhydride
0.5-30% of reaction product with N, N-dialkylaminoalkylamine A metal material for cold plastic working characterized by having a lubricating film on the surface,
The lubricating coating, the following components A~D, A + B + C + D cold plastic working a metal material, characterized in that it contains in the range of less than the mass percentage of the total amount of.
A component: 10-30% of at least one selected from the group consisting of borate, silicate, and molybdate ,
B component: 5-30% of salt of fatty acid and metal ,
Component C: 10-84.5% of at least one selected from the group consisting of calcium hydroxide, magnesium hydroxide, and barium hydroxide ,
Component D: As a solid dispersant, the number average molecular weight is 10,000 to 50,000,
Copolymer of α-olefin and maleic anhydride
0.5-30% of reaction product with N, N-dialkylaminoalkylamine A metal processed product obtained by plastic processing the metal material for cold plastic processing according to claim 2.

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