KR20000023075A - Process of forming lubricative film suitable for cold forging of metallic material - Google Patents

Abstract

PURPOSE: An excellent method for formation of lubricating film,which does not produce any sludge and results in the high productivity. and a lubricating film therefrom, which is suitable for cold forging of metal, are provided. CONSTITUTION: The lubricating film is prepared by: (i) forming 6-20 gram/square meter of phosphate substrate on the metal by electrolyzing an electrolyte containing 20-50 gram/liter of zinc ion, 20-70 gram/liter of phosphate ion and 30-80 gram/liter of nitrate ion with 20-100 ampere/square meter using metal as cathode; and (ii) covering the substrate with water type or oil type lubricant after de-scaling the metal with either using acid or mechanical de-scaling accompanied by using acid.

Description

PROCESS OF FORMING LUBRICATIVE FILM SUITABLE FOR COLD FORGING OF METALLIC MATERIAL}

The present invention relates to a method for forming a lubricating film suitable for cold forging of metal materials.

In cold forging of metal, a lubricating film is provided on the surface of the metal before cold forging. The lubricating film is usually produced by two processes. In the first process, the substrate layer is chemically formed on the surface of the metal. For example, in carbon steels, phosphate layers such as zinc phosphate, zinc-iron phosphate, zinc-calcium phosphate and manganese phosphate are formed on the surface of the steel. Similarly, a oxalate layer is formed in stainless steel. The aluminum fluoride compound layer is formed in aluminum. Copper oxide layers were formed on copper. The titanium-fluoride compound layer is formed on titanium.

In the second process, the substrate layer is covered with an aqueous or oil lubricant.

Most commonly used are lubricant coatings whose substrate is a phosphate layer and covered with an oil lubricant of an alkali metal salt of a fatty acid. In this case, a lubricating film having triple layers of ginseng salt, metal metal salt and metal salt was formed on the surface of the metal.

The reaction is represented by the following equation.

Zn ₃ (PO ₄ ) ₂ 4H ₂ O + 6C ₁₇ H ₃₅ COONa → 3 (C ₁₇ H ₃₅ COO) ₂ Zn + 2Na ₃ PO ₄ + 4H ₂ O. … … … One

Usually, the above lubricating film is produced by performing the following steps 1 to 6.

① Descaling by combining acid solution or mechanical descaling with acid solution.

② water washing.

③ Forming a substrate by dipping a metal material into the treatment solution.

④ Defensive

⑤ Treatment with reactive metal salt

⑥ Dry

However, the above conventional process causes some environmental problems, and does not satisfy the lubricating properties of the lubricating film. For the first problem, the formation of sludge in the treatment solution of step 3 is exemplified. For example, when steel is immersed in a phosphate matrix that forms a liquid, large amounts of sludge are formed in the manufacturing process of the phosphate substrate and the sludge must be removed out. Similarly, in the formation of oxalate substrates, fluorinated compound substrates and oxide substrates, large amounts of sludge have to be formed and removed and treated, increasing production costs. JP-197581A shows how to reduce the amount of sludge. However, this only reduces the amount of sludge which is usually half the process, requiring further reduction.

With regard to the second problem, for example, the disposal of the treatment solution in step (3). Conventionally, other substrate layers than phosphate coatings have been formed for stainless steel, aluminum, copper and titanium. However, in this process, the substrate layer can easily change its properties depending on the component change of the treatment solution. And frequent regeneration of the treatment solution was performed to maintain a substrate with uniform properties, resulting in a large amount of waste solution results. The waste solution must be treated until it is not completely harmful.

As regards the third problem, the temperature of the treatment solution is taken as an example in step ③. For example, phosphate substrates are usually formed at temperatures above 80 ° C. And a oxalate substrate was formed above 90 degreeC. The high temperature of the treatment solution worsens the working environment, accelerates the corrosion of the equipment and increases the manufacturing cost. JP2-197581A describes a method for reducing the temperature below 50 to 60 ° C. . However, additional low temperatures will be desirable.

As regards the fourth problem, the nature of the substrate is exemplified. As described above, the phosphate substrate produces a reactive metal salt lubricating film with good lubricating properties. However, the reactive metal salt lubricating film is not formed on the copper oxide substrate or the titanium fluoride substrate.

In contrast, the reactive metal salt lubricating film is excessively formed in the oxalate substrate and the aluminum-fluoride substrate and causes problems in cold forging by increasing the lubrication problem in the cavity of the tool.

In the forging of stainless steel, a lubricating film composed of a oxalate substrate and molybdenum disulfide was used. However, in this process, the hydroxide substrate is often degraded during the preheating of the material.

As for the fifth problem, the thickness of the substrate is exemplified. As described above, the substrate layer is conventionally formed by dipping a metal material into the treatment solution. In this process, the treatment solution reacts with the surface of the metal material and deposits the reactant on the surface of the metal material as a substrate. However, the reaction would terminate when the substrate layer had reached a certain thickness, and no further substrate formation occurred. Attempts have been made to increase the thickness of the substrate by increasing the concentration and temperature of the treatment solution. However, this did not readily form a substrate with sufficient and uniform thickness.

JP6-322592A shows an electrolytic process using a pulse current to make a metal material as an anode and to make a phosphate substrate of the metal material. However, this process forms a large amount of sludge because the metal material is used as the anode.

It is an object of the present invention to provide a new process for forming a suitable lubricating film for cold forging of metallic materials. In cold forging, it may be desirable for the thickness of the substrate to be of sufficient thickness, for example 6-20 g / m ² . In conventional processes, the formation of thick substrates produces a large amount of sludge. It is an object of the present invention to provide a thick substrate without sludge formation.

In conventional processes, the formation of thick substrates is accompanied by a decrease in productivity because the treatment solution and metal material contact time must be long enough. It is an object of the present invention to provide a thick substrate at high productivity.

In conventional processes, the formation of thick substrates on stainless steel is difficult. It is an object of the present invention to provide a thick substrate layer over metal material, for example stainless steel, than carbon steel.

That is, the present invention,

1) Metallic material as an anode using an electrolyte containing 20-50 g / l Zn ions having a current of 20-100 A / dm ² , 20-70 g / l phosphate ions and 30-80 g / l nitrate ions; The formation of a substrate of 6-20 g / m ² on the metal material by electrolysis and the use of acid to cover the substrate with an aqueous or oil lubricant or with a mechanical descaling and acid in advance A method of forming a lubricating film suitable for cold forging of a metal material, characterized in that it is descaled.

2) A method for forming a lubricating film suitable for cold forging of a metal material, characterized in that the metal material obtained in the above (1) is further cold drawn at a cross sectional area reduction rate of 15% or less.

3) The above (1) or (2), wherein the electrolyte further comprises one or more oxides selected from nitrate ions, hydrogen peroxide and chlorine ions and one selected from Mg, Al, Ca ,, Mn, Cr, Fe, Ni, Cu A method of forming a lubricating film suitable for cold forging of a metal material, characterized by containing the above metal ions.

4) The method for forming a lubricating film suitable for cold forging of a metal material according to the above (3), wherein the electrolyte contains Ca ions and the molar ratio of Ca ions to zinc ions is 0.1 to 2.0.

5) The method according to any one of (1) to (4), wherein the metal material makes contact with the control liquid between descaling and substrate formation, wherein the control liquid contains titanium colloid or fine metal phosphate particles of 5 μm or less. A method for forming a lubricating film suitable for cold forging of a metal material, characterized in that.

6) The forging for cold forging metal materials according to any one of (1) to (5), wherein the aqueous lubricant is at least one made of an alkali metal fatty acid salt, a metal alkali metal salt and a solid lubricant. To form a suitable lubricating film.

7) The oil lubricant according to any one of (1) to (5), wherein the oil lubricant is at least one produced by inorganic, animal oil and synthetic ester oil to form a suitable lubricating film for cold forging of metal materials. Way

In the present invention, the metal material must be descaled. In such descaling, acid solutions are used, and mechanical descaling is involved and acid descaling may also be preferred. Acid descaling is usually carried out by contacting the acid solution with the metal material and, in equivalent cases, by using an electrolyte method using the metal material as the cathode or as the anode. Mechanical descaling is usually performed by a bending process or shot blasting.

In the present invention, descaling is carried out in a manner similar to the conventional method. Metallic material should be washed after treatment with acid solution.

In the present invention, an electrolyte containing phosphate ions is used to form a substrate on a metal material. Also in conventional processes, a similar treatment solution containing phosphate ions was used to form a substrate of phosphate.

As is well known, phosphoric acid (H ₃ PO ₄ ) in aqueous solution is separated in three steps as described below.

Step _{Ⅰ: H 3 PO 4 → H} 2 PO 4 - + H +

Step II: H ₂ PO ₄ → HPO ₄ ^2- + H ⁺

Step III: HPO ₄ ^2- → PO ₄ ^3- + H ⁺

The electrolyte of the present invention as well as the treatment solution of the conventional method should also contain Zn ²⁺ ions. When step I occurs, in step I H ₂ PO ₄ ⁻ combines with Zn ²⁺ to form a substrate of Zn (H ₂ PO ₄ ) ₂ . In a similar manner, the substrate of Zn (HPO ₄ ) and Zn ₃ (PO ₄ ) ₂ are formed in steps II and III, respectively. In the substrate, Zn ₃ (PO ₄ ) ₂ has the most desirable properties as a substrate.

However, the separation of steps I to III does not occur strongly in acid solution because phosphoric acid (H ₃ PO ₄ ) is a very weak acid. Therefore, in order to proceed with the separation by reaching step III and to obtain a substrate of Zn ₃ (PO ₄ ) ₂ , some chemical reaction is needed to reduce the concentration of H ⁺ ions. In conventional processes, the reduction of H ⁺ ion concentration is carried out by dissolving iron ions in solution as in the formula Fe + 2H ⁺ → Fe ²⁺ + H ₂ .

That is, in the conventional process, the concentration of H ⁺ ions is reduced near the surface of the metal material by dissolving iron ions. The decomposition of phosphoric acid proceeds in step III. And PO ₄ ^3- ions are generated and a substrate of Zn ₃ (PO ₄ ) ₂ is obtained. As described above, in the conventional process, the substrate of Zn ₃ (PO ₄ ) ₂ is obtained by dissolving iron in the treatment solution and forming Fe ²⁺ . However, the ions formed in the Fe ²⁺ treatment solution chemically turn into insoluble compounds and make sludge in the treatment solution.

In the present invention, the reduction of H ⁺ ion concentration is effected by the electrical discharge of H ⁺ ions on the cathode of the metal material as in the formula 2H ⁺ → H ₂ + 2e. That is, in the present invention, H ⁺ ions present near the surface of the metal material are electrically attached toward the cathode of the metal material, the concentration of H ⁺ ions is reduced near the surface of the metal material, and the separation of the phosphate ions is performed. Proceeding in III, PO ₄ ^3- ions are generated and a Zn ₃ (PO ₄ ) ₂ substrate is obtained.

As described above, in the present invention, the Zn ₃ (PO ₄ ) ₂ substrate is obtained by electrical discharge of H ⁺ ions, but not by dissolving iron. Thus, Fe ²⁺ ions are not formed in the electrolyte, and there is no insoluble mixture and sludge is not formed in the electrolyte.

In the above invention, an electrolytic solution containing zinc ions: 20-50 g / l, phosphate ions: 20-70 g / l and nitrate ions: 30-80 g / l is used and forms a thick phosphate substrate of 6-20 g / m ² . do. When the zinc ions are 20 g / l or less, the phosphate ions are 20 g / l or less and the nitrate ions are 30 g / l or less and the formation of substrate formation is too low compared to the long time required to form a substrate of 6 to 29 g / m ² . However, when the zinc ion is 50 g / l or more, the phosphate ion is 70 g / l or more and the nitrate ion is 80 g / l, and no further special advantage is obtained.

In the present invention, cathode electrolysis is carried out at a current density of 20-100 A / dm ² . Phosphate substrates are formed even at current densities of 20 A / dm ² or less, but a long time is required to form a substrate of 6 to 20 g / m ² . However, no additional special advantage is obtained when the current density is above 100 A / dm ² .

As previously described, in conventional processes, the phosphate substrate is obtained by dissolving the metal material in the treatment solution. Thus, when the metal material is not dissolved in the treatment solution, no phosphate substrate is formed. For example, stainless steel is difficult to dissolve in the treatment solution, which does not reduce the concentration of H ⁺ ions, the decomposition of phosphates does not proceed, and the Zn ₃ (PO ₄ ) ₂ phosphate substrate is a stainless steel in conventional processes. It is not formed on the stomach.

On the other hand, in the present invention, in the vicinity of the stainless steel, H ⁺ ions are deposited toward the stainless steel, electrically discharged on the stainless steel, reducing the concentration of the H ⁺ ions, separation of the phosphate proceeding in step III, and Zn ₃ (PO ₄ ) ₂ substrate is formed on the stainless steel surface.

In addition, the electrolyte of the present invention contains at least one metal ion selected from Mg, Al, Ca, Mn, Cr, Fe, Ni, Cu. In this case, for example, Mg ₃ (PO ₄ ) ₂ , AlPO ₄ , Ca ₃ (PO ₄ ) ₂ , CaHPO ₄ , Mn ₃ (PO ₄ ) ₂ , Mn ₂ Fe (PO ₄ ) ₂ , (Mn _{1- x} , Fe _x ) ₅ H ₂ (PO ₄ ) ₄ , Cr ₂ (PO ₄ ) ₂ , Fe (PO ₄ ) ₂ , FePO ₄ , Zn ₃ (PO ₄ ) ₂ , ZnFe ₂ (PO ₄ ) ₂ , Zn ₂ A phosphate substrate of Ca (PO ₄ ) ₂ , Zn ₂ Mn (PO ₄ ) ₂ was further formed, and these phosphates are applied as the preferred substrate. As described above with respect to one example of stainless steel, it becomes clear from the above that the phosphate substrate described above is formed for many kinds of metal substrates because they are formed without dissolving the metal material in solution.

In conventional processes, the metal material does not dissolve in the treatment solution, and the metal ions generated from the metal material combine with useful components in the treatment solution to form sludge, and the useful components in the treatment solution are associated with the formation of sludge and Consumed at the same time.

In the present invention, the metal material does not dissolve in the electrolytic solution because the metal material is set as the negative electrode, and the constituents in the useful electrolytic solution are not consumed to form insoluble sludge. Thus, in the present invention, the consumption of useful constituents in the solution is much less than in the stern process and the formation of sludge is prevented.

In conventional processes, the temperature of the treatment solution must be high enough to efficiently dissolve the metal material into the treatment solution. On the other hand, in the present invention, dissolution of the metal material into the solution is unnecessary, and the electric discharge of H ⁺ ions proceeds efficiently at room temperature.

Thus, in the present invention, the heat consumption according to the process is much less than in the conventional process, and also in the conventional process, the formation of the phosphate substrate is difficult for stainless steel or copper. On the other hand, in the present invention, the phosphate substrate is easily formed from stainless steel or copper, and a reactive metal salt lubricating film having excellent lubricating properties is easily applied to stainless steel or copper.

Therefore, in the present invention, the thickness of the substrate is easily controlled in an appropriate range. In conventional processes, high temperature, extremely concentrated treatment solutions were usually used to form thick substrates. However, in conventional processes, a large amount of useful components in the treatment solution adhere to the metal material and are consumed and removed from the treatment solution. The heat consumption is also sufficiently high in this case.

On the other hand, in the present invention, the thickness of the substrate can be easily and accurately controlled to the required thickness by setting the current density to an appropriate value. In the present invention, electrolysis is preferably carried out by using an electrolyte having a temperature from room temperature to 80 ° C. and a current density of 20 to 100 A / dm ² . The electrolytic solution of the present invention contains phosphate ions: 20 to 70 g / l, nitrate ions: 30 to 80 g / l, and zinc ions: 20 to 50 g / l. The molar ratio of metal ions to phosphate ions is preferably 0.3 to 2, and the molar ratio of nitrate ions to phosphate ions is preferably in the range of 0.1 to 3. If phosphate ions or zinc ions are lower than the above ranges, the formation of phosphate substrates is difficult, and if higher than this range, it would be uneconomical by increasing the consumption of the electrolytic solution to remove adhesion on the metal material. If the nitrate ion is lower than 30 g / l, precipitation of metal zinc occurs and no lubricating substrate is obtained. If the molar ratio of metal ions to phosphate ions is lower than 0.3, the formation of the phosphate substrate becomes difficult, and if the molar ratio is higher than 2, it becomes uneconomical.

If the molar ratio of nitrate ions to phosphate ions is 0.3 or less, plating of the metal zinc will proceed, and at a ratio higher than 0.3, the crystals in the phosphate substrate will be rough and large.

In the present invention, an oxidant selected from nitrate ions, hydrogen peroxide and chlorine ions is further contained in the electrolyte. The oxidant preferably promotes the formation of a phosphate substrate that prevents precipitation of metal ions.

In addition, the electrolyte preferably contains zinc and calcium ions. And the molar ratio of calcium ions to zinc ions is preferably in the range of 0.1 to 2. In the absence of calcium ions, the zinc phosphate (Zn ₃ (PO ₄ ) ₂ .4H ₂ O) substrate will be obtained by cathodic electrolysis. A bound substrate containing zinc phosphate (Zn ₃ (PO ₄ ) ₂ .4H ₂ O) and zinc calcium phosphate (Zn ₂ Ca (PO ₄ ) ₂ · 2H ₂ O) is preferred as the substrate, and As such it will be obtained by an electrolyte having a preferred molar ratio of calcium ions to zinc ions. The higher the molar ratio, the higher the zinc phosphate-calcium can be made. At molar ratios of 0.1 or less, only zinc phosphate substrates are prepared but at ratios higher than 2, zinc phosphate-calcium phosphate (CaHPO ₄ .2H ₂ O) will be produced instead.

The aqueous lubricants used in the present invention should preferably contain either alkali metal or metal alkali metal salts or fatty acid salts of solid lubricants. By forming a phosphate substrate in the first process and then forming a lubricating film as the second process with the use of the lubricant, the formation of a good lubricating film is not possible in conventional processes where cathodic electrolysis is not performed. It is possible even on the metallic material of titanium. And the lubricating coating enables large deformation of the metal material by one forging in the cold forging process. As fatty acid salts of alkali metals, saturated or unsaturated fatty acid salts of sodium, potassium, lithium can be used. In addition, dimer acids or trimer acids of unsaturated fatty acids having double bonds or more may be used. The fatty acid salt of the alkali metal is contained 1 to 20% by weight in the aqueous lubricant. And aqueous lubricants are made to cover the substrate at 60-90 ° C. It is desirable to immerse the metal material into the aqueous lubricant or to pour the aqueous lubricant over the metal material.

Metallic metal salts or solid lubricants can be used by distributing them into water, and the method for covering the substrate is similar to that of fatty acid salts of alkali metals. For aqueous metal alkali metal salts, metal salts of higher fatty acids can be used. And for high fatty acids, lauric acid, myristic acid, palmitic acid, stearic acid and behenic acid can be applied. And for metals, calcium, aluminum, magnesium, barium, zinc and lead can be applied.

Among them, calcium stearate can be used most preferably. For solid lubricants, molybdenum disulfide, graphite, tungsten disulfide, graphite-fluoride, bromine nitride, talc, mica, PTFE (poly-tetrafluoride-ethylene) can be used. Also, alkali metals Any of the fatty acid salts, metal alkali metal salts and solid lubricants of may be used in admixture with each other.

Similarly, at least one oil lubricant should be selected from mineral oils, animal or vegetable oils and synthetic ester oils. For mineral oils, machining oils, turbine oils, spindle oils can be used, and for animal or plant oils, palm oil, rapeseed oil, coconut oil, castor oil, lard oil, bovine oil, fish oil, etc. Can be used. In the synthetic ester oil, polyol esters of fatty acids having a structure of neopentyl-polyol ester and the like can be used. And in addition, excessive pressure adhesion of chloric acid groups, sulfuric acid groups or phosphoric acid groups is added to the oil lubricant.

1 shows the cold forging test used for the evaluation of the lubricating film.

Now, an example of the lubricating film formation of the present invention will be described. The lubricating film forming of the present invention can be suitably applied to batch system operation and in-line system operation. The batch system here includes a barrel process that is widely applied to a forged part process.

The metal material treated in the present invention is an electrically conductive material such as carbon steel, chromium steel, chromium-molybdenum steel, nickel-chromium steel, nickel-chromium-molybdenum steel, stainless steel, boron steel, manganese steel, and aluminum, magnesium, titanium And nonferrous materials such as copper and the like.

Prior to the application of the present invention, the surface of the metallic material must be cleaned. The washing includes degreasing and descaling. In degreasing, grease adhered onto the metal material is removed by using alkaline degreasing agents available on the market. In the descaling, the surface scale of the metal material formed in the process before the heat treatment was removed by using an acid solution and a mechanical descaling. As the acid solution, sulfuric acid, hydrochloric acid, nitric acid, hydrofluoric acid and zirconium hydrogen fluoric acid were used. An electrolytic process was applied to descale with acid solution.

After treatment in the acid solution, the metal material must be sufficiently washed in water to prevent the acid solution from penetrating into the substrate to form the dissolution of the next process. Regarding the mechanical descaling, rolling bending method, shot-blasting method, air-blasting method and liquid honing method were used. Washing with acid solution was recommended after mechanical descaling.

The metal material may or may not be in contact with the control solution containing fine phosphate particles or colloidal titanium of 5 μm or less in particle size. In the next substrate formation process the phosphate substrate formation rate is increased, and in the next process the finely crystallized phosphate substrate is obtained by contacting the metal material with the control solution. The rate of formation of the phosphate substrate is also increased by heating the metal material immediately before the substrate formation process.

In the next process of phosphate substrate formation, an electrolytic process was carried out using the metal material as the direct current and as the cathode. Any form of direct current with an example of sinusoidal wavelength, spherical pulse wavelength and square wavelength and wavelength combined with the above was used. As for the anode in the electrolytic process, carbon anode, stainless anode, platinum anode, titanium-alloy anode and DSE (titanium-platinum plated alloy) anode were used. As the metal ions, a consumable type metal anode composed of the same kind of metal contained in the solution was used. In the consumable type metal anode, metal ions in the solution are supplied from the consumable type metal anode.

After phosphate substrate formation, the metal material is washed with water to remove the substrate forming solution from the metal material, and a lubricant is applied to the metal material.

In the present invention, an oil lubricant as well as an aqueous lubricant is used in the liquid state, and the substrate is covered by immersing the metal material inside the liquid lubricant or by spraying the liquid lubricant on the metal material.

In the case of an aqueous lubricant, excess water in the aqueous lubricant adhering to the metallic material is preferably removed by using a suitable dryer. The metal material with the above lubricating film can be used for cold forging without any further treatment. However, in accordance with the new findings of the inventors, it has been found that more preferred results can be obtained when the metal material is further subjected to cold drawing with a section shrinkage of no more than 15%.

Example

[Metal Materials Used for the Examples]

Rod-shaped S45C (medium carbon steel), SUS304 (stainless steel), A6061 (aluminum) and the like each having a diameter of 30 mm were used in the examples and comparative examples of the present invention.

[Substrate and amount of lubricant]

After the formation of the lubricating film, the amount of substrate and the amount of lubricant were measured in the following manner.

W 1: Weight of the specimen covered with lubricant.

W 2: Weight of the specimen after peeling off the lubricant from the substrate using a solvent (a mixed solution of isopropyl alcohol: 6, normal heptane: 3, ethyl cellosolve: 1).

W 3: Weight of specimen after removing substrate from metal by using 5% chromic acid solution.

Amount of substrate: (W 2-W 3) / (surface area of specimen)

Amount of lubricant: (W 1-W 2) / (surface area of specimen)

[Lubrication characteristics]

The lubricating properties of the lubricating film were evaluated in the following manner. 1 shows an outline of a cold forging test. 18mm, 20mm, 22mm, respectively. … 12 pieces of columnar specimens with heights of 38 mm and 40 mm were provided. Some of these are shown in FIG. 1 (A). After the lubricating film was formed, each specimen was mounted in a cavity of a die, and cold forged using a punch in turn, as shown in FIG. 1 (B). 1 (C) shows the cold forged specimen thus obtained. The surface of the cold forged specimen was visually observed and specimens with surface defects were removed. The maximum depth Z (mm) of the cold forged specimen cavity removed was used for the evaluation of the lubrication properties.

[Sludge formation]

After formation of the substrate, the substrate forming solution was visually observed. (Circle) shows the form without sludge formation, and x represents sludge formation.

[Inventive Examples 1 to 17 and Comparative Examples 1 to 10]

An overview of the test results is shown in Table 1. In the column of substrate forming solution of Table 1, PALBOND 181 is a conventional phosphate that forms a solution in chemical reaction form, and FELBOND is used to form a solution in chemical reaction form commonly used for stainless steel. Conventional oxalates and ALBONDs are substrates that form solutions in the form of chemical reactions commonly used for aluminum.

As observed from the column of the substrate forming process and from both columns of the substrate in Table 1, a large amount of substrate of 7.4 to 13.8 g / m ² was formed in a short period of 3 to 20 seconds in Examples 1 to 17 of the present invention, In Comparative Examples 1-4, 8 and 10, 10 minutes were required to form a thin phosphate substrate of 0.2-6.5 g / m ² .

Thus, it was evident that the effect of phosphate substrate formation in the inventive examples was better than in the comparative example.

In addition, as observed from the sludge formation column of Table 1, sludge was not observed in any of the Examples 1 to 17 of the present invention. On the other hand, in Comparative Examples 1 to 10, sludge was observed in most cases.

[18 to 26 Inventive Examples and 11 to 16 Comparative Examples]

An overview of the test results is shown in Table 2. In the column of substrate forming solution of Table 2, PALBOND 187 is a phosphate forming solution in chemical reaction form with high concentration. As observed from the column of the substrate formation process and from both columns of the substrate in Table 2, a large amount of substrate of 8.4 to 16.9 g / m ² was produced in a period of 5 seconds in the examples of the present invention.

On the other hand, in Comparative Examples 11 to 16, a small amount of 0.2 to 6.5 g / m ² substrate was produced in an equivalent period of 5 seconds. In addition, as observed from the sludge forming column of Table 2, sludge was not observed in any of the examples of the present invention of 18 to 26. On the other hand, in Comparative Examples 11 to 16, sludge was observed in most cases in an equivalent period of 5 seconds.

Metal material control Component of Substrate Formation Solution (g / l) Substrate formation process slush Substrate Amount (g / m ² ) Lubricant amount (g / m ² ) Lubricant Characteristics (mm) Sludge formation Fair evaluation Zn ²⁺ PO ₄ ^3- No ₃ ^1- fair ℃ A / dm ² time Embodiment of the Invention One S45C Colloidal titanium 22 28 31 Cathode Electrolysis 80 20 10sec Lv235 * 4 11.6 5.3 48 ○ ○ 2 〃 33 40 46 80 25 5sec Lv235 * 4 10.5 4.9 48 ○ ○ 3 〃 45 54 62 80 35 3sec Lv235 * 4 9.9 5.1 48 ○ ○ 4 〃 22 28 31 80 20 10sec FAVE4612 * 5 13.4 2.3 44 ○ ○ 5 〃 33 40 46 80 25 5sec FAVE4612 * 5 12.1 2.2 44 ○ ○ 6 〃 45 54 62 80 35 3sec FAVE4612 * 5 12.3 2.6 44 ○ ○ 7 〃 22 28 31 80 20 10sec Palm oil 13.8 5.7 44 ○ ○ 8 〃 33 40 46 80 25 5sec Palm oil 12.9 5.4 44 ○ ○ 9 〃 45 54 62 80 35 3sec Palm oil 13.6 5.8 44 ○ ○

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Bourne State Room Example 10 S45C Colloidal titanium 22 28 31 Cathode Electrolysis 80 20 20s. Lv235 * 4 7.4 5.4 44 ○ ○ Pulse current 11 〃 22 28 50 80 20 10sec 〃 7.7 4.2 52 ○ ○ Ca ²⁺ : 5g / l 12 A6061 〃 33 40 46 80 25 5sec 〃 8.3 5.6 48 ○ ○ 13 〃 33 40 51 80 25 5sec FAVE4612 * 5 9.6 5.2 52 ○ ○ Al ³⁺ : 1g / l 14 SUS304 〃 33 40 51 80 25 5sec 〃 8.3 2.4 48 ○ ○ Mg ²⁺ : 1g / l 15 〃 33 40 46 80 25 5sec FAVE4649 * 6 9.7 17.4 36 ○ ○ 16 〃 33 40 46 80 25 5sec Lv235 * 4 8.6 6.8 32 ○ ○ 17 〃 45 54 62 80 80 3sec FAVE4649 * 6 10.2 18.0 36 ○ ○ Comparative example One S45C - ARM BOND181X * 1 Chemical reaction 80 - 10min Lv235 * 4 5.3 5.5 44 × × 2 - ARM BOND181X * 1 80 - 10min FAVE4612 * 5 6.2 3.5 40 × × 3 - ARM BOND181X * 1 80 - 10min Palm oil 6.5 2.7 32 × × 4 - ARM BOND181X * 1 40 - 10min Lv235 * 4 1.3 1.5 32 × ×

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Comparative example 5 S45C - 0.15 0.23 0.31 Anode Electrolysis 80 10 30sec Lv235 * 4 4.5 1.6 32 × × 6 - 0.15 0.23 0.31 80 10 45s. 〃 5.6 1.9 36 × × Pulse current 7 SUS304 - Pelbond A * 2 Chemical reaction 95 - 10min FAVE4649 * 6 11.0 17.2 16 × × 8 - ARM BOND181X * 1 80 - 10min 〃 0.3 10.2 0 ○ × 9 A6061 - Albond A * 3 90 - 1min Lv235 * 4 10.2 4.4 52 × × 10 - ARM BOND181X * 1 80 - 10min 〃 0.2 0.1 16 ○ ×

* 1 PALBOND 181X: Conventional solution for zinc-phosphate substrate (manufactured by Nippon Parkerizing Co., Ltd.)

* 2 FELBOND A: Conventional solution for oxalate substrates (manufactured by Nippon Parkerizing Co., Ltd.)

* 3 ALBOND A: Conventional solution applied for aluminum (manufactured by Nippon Parkarizing Co., Ltd.)

* 4 Valve 235: Reactive metal salt lubricant (manufactured by Nippon Parkering Co., Ltd.)

* 5 Valve 4612: Unreacted metal salt lubricant (manufactured by Nippon Parkering Co., Ltd.)

* 6 Pave 4649: Molybdenum disulfide group (manufactured by Nippon Parkering Co., Ltd.)

Metal material control Component of Substrate Formation Solution (g / l) Substrate formation process slush Substrate Amount (g / m ² ) Lubricant amount (g / m ² ) Lubricant Characteristics (mm) Sludge formation Fair evaluation Zn ²⁺ PO ₄ ^3- No ₃ ^1- fair ℃ A / dm ² time Embodiment of the Invention 18 S45C Colloidal titanium 45 56 62 Cathode Electrolysis 80 35 5sec Lv234 14.3 3.8 48 ○ ○ 19 〃 45 56 62 80 85 2sec Lv234 10.5 2.1 48 ○ ○ 20 〃 45 56 62 80 35 5sec Fave4612 16.9 3.6 44 ○ ○ 21 〃 45 56 62 80 85 2sec Fave4612 11.3 3.7 44 ○ ○ 22 〃 45 56 62 40 35 5sec Lv234 9.2 3.0 44 ○ ○ 23 〃 45 56 62 40 35 5sec Lv234 8.4 3.2 52 ○ ○ 24 〃 45 56 62 80 35 5sec Fave4649 10.8 9.8 36 ○ ○ 25 〃 21 66 72 80 35 5sec Fave4649 9.8 10.1 36 ○ ○ Ca ²⁺ : 2g / l 26 〃 45 56 62 80 35 5sec Fave4649 12.3 10.4 36 ○ ○

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Comparative example 11 S45C - Arm Bond187X * 7 Chemical reaction 85 - 5sec Lv234 5.3 3.5 44 × × 12 - Arm Bond187X * 7 85 - 5sec Fave4612 6.2 2.2 40 × × 13 Colloidal titanium Arm Bond187X * 7 85 - 5sec Lv234 4.5 2.7 32 × × 14 Phosphate Particles Arm Bond187X * 7 85 - 5sec 〃 3.3 2.5 32 × × 15 SUS304 - Pel Bond A 95 - 5sec Fave4649 0.9 2.7 16 × × 16 - Arm Bond187X * 7 85 - 5sec 〃 0.2 0.3 0 ○ ×

* 7 PALBOND 187X: Phosphate to form a solution with high concentration (manufactured by Nippon Parkerizing Co., Ltd.)

In accordance with the present invention, a thick phosphate substrate was prepared on the surface of the metal material without the formation of sludge in solution. According to the invention, thick phosphate substrates have been produced very efficiently. In accordance with the present invention, thick phosphate substrates have been prepared on surfaces of other metallic materials other than steel such as stainless steel, copper, aluminum and titanium. The lubricating film of the present invention produced by covering a substrate with a lubricant exhibited excellent properties in cold forging of metallic materials.

Claims (7)

Using an electrolyte containing 20 to 50 g / l Zn ions with a current of 20 to 100 A / dm ² , 20 to 70 g / l phosphate ions and 30 to 80 g / l nitrate ions, and a metal material as the cathode Thereby forming a substrate of 6-20 g / m ² on the metal material by electrolysis and using an acid or mechanical descaling and accompanying acid to cover the substrate with an aqueous or oil lubricant. A method for forming a lubricating film suitable for cold forging of a metal material, characterized in that the. 2. A method according to claim 1, wherein the obtained metal material is further cold drawn at a cross sectional area reduction rate of 15% or less. The method of claim 1 or 2, wherein the electrolyte further comprises at least one oxide selected from nitrate ions, hydrogen peroxide and chlorine ions and at least one metal ion selected from Mg, Al, Ca ,, Mn, Cr, Fe, Ni, Cu. A method for forming a lubricating film suitable for cold forging of a metal material, characterized in that it contains. 4. The method according to claim 3, wherein the electrolyte contains Ca ions and the molar concentration ratio of Ca ions to zinc ions is 0.1 to 2.0. The metal material of claim 1, wherein the metal material is in contact with the control liquid between descaling and substrate formation, wherein the control liquid contains titanium colloid or fine metal phosphate particles of 5 μm or less. A method for forming a lubricating film suitable for cold forging of a metal material, characterized in that. The cold forging of a metal material according to any one of claims 1 to 5, wherein the aqueous lubricant contains at least one selected from fatty acid salts of alkali metals, metal alkali metal salts and solid lubricants. To form a suitable lubricating film. 6. A method according to any one of claims 1 to 5, wherein the oil lubricant contains at least one selected from minerals, animal oils and synthetic ester oils.