JPH04246499A - Lubricating oil for plastic working - Google Patents

Abstract

PURPOSE:To prepare the title oil which is not flammable, does not pollute a working environment, has a good stickiness and a high lubricity, and extends the life of tools. CONSTITUTION:The title oil is prepd. by dissolving and/or dispersing 0.2-40wt.% alkali metal of an arom. compd. having at least two carboxyl groups and an m.p. or a decomposition temp. of 300 deg.C or higher, 0.05-20wt.% water-sol. stickiness improver, 0.2-5wt.% alkali metal salt of a 10-16C alkanedioic acid, and 0.5-15wt.% surfactant in water.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricant used when carbon steel, alloy steel, and non-ferrous metals are subjected to warm or hot plastic working such as forging, rolling, wire drawing, and extrusion. The lubricant of the present invention supplies oil between the tool and the workpiece during plastic working,
A plastic processing lubricant that is used to reduce friction between tools and workpieces during processing, prevent seizures, improve mold release properties, and improve the working environment in place of graphite-based lubricants. Useful as an oil agent.

0002

BACKGROUND OF THE INVENTION A lubricant prepared by dispersing graphite in oil or water is used as a lubricant for warm or hot plastic working of metals. Dispersion in oil has good lubricity, but there are problems with fire and smoke generation, and cooling performance is also poor. Those dispersed in water have excellent cooling properties and are free from the risk of fire, but they have poor lubricity, so they are used differently depending on processing conditions.

0003

[Problems to be Solved by the Invention] However, although non-water dispersion type tools are somewhat satisfactory in terms of extending tool life, there is always a risk of ignition, and water dispersion type tools lack lubricity and extend the life of the tool. I am not satisfied with this point.

[0004] Furthermore, since lubricating oils containing graphite as a main component pollute the working environment, a lubricating oil that does not use graphite is desired. In light of the above-mentioned circumstances, it is an object of the present invention to provide a lubricant that does not pose a risk of ignition, does not pollute the working environment, and can extend the life of tools.

[0005]

[Means for Solving the Problems] As a result of extensive research in order to solve the above problems, the present inventors have found that a specific aromatic hydrocarbon alkali metal salt and a water-soluble adhesion improver are mixed in a specific ratio.
Furthermore, the present invention was achieved by discovering that the object of the present invention can be achieved by a lubricating oil agent in which a specific alkali metal alkanedioic acid salt and a surfactant are dissolved and/or dispersed in water in a specific ratio. .

That is, the present invention comprises 0.2 to 40% by weight of an aromatic hydrocarbon alkali metal having two or more carboxyl groups and a melting or thermal decomposition temperature of 300°C or higher, and 0.05 to 40% by weight of a water-soluble adhesion improver. 20% by weight and carbon number 10-1
Dissolve 0.2 to 5% by weight of the alkanedioic acid alkali metal salt No. 6 and 0.5 to 15% by weight of the surfactant in water and/or
Or, it is characterized by being dispersed.

[0007] The effect of the present invention is only recognized when the above four components are contained in water in a specific ratio, and if even one component is missing or the ratio is deviated, the effect cannot be obtained. I can't do it.

[0008]

[Operation] According to the present invention, when performing warm or hot plastic working of metal, a specific aromatic hydrocarbon alkali metal salt, a water-soluble adhesion improver, and a specific alkanedioic acid alkali metal are added to the tool surface. The film formed by a mixture of salt and surfactant in a specific ratio is uniform, thick, strong, and thermally stable, reducing the coefficient of friction between the tool and workpiece and increasing separation. It also shows type characteristics.

Examples of aromatic hydrocarbon alkali metal salts having two or more carboxyl groups and a melting or thermal decomposition temperature of 300° C. or higher, which are the first component of the present invention, include sodium isophthalate, potassium terephthalate, and trisulfate. Examples include, but are not limited to, lithium mellitate, sodium naphthalene 1,4 dicarboxylate, and sodium naphthalene 1,5 dicarboxylate. These are aromatic compounds that are crystalline and melt or thermally decompose at temperatures above 300°C, and have functional groups that easily react with metals. Any material may be used as long as it exhibits good lubricity and does not leave behind any residue that may adversely affect the workpiece after machining. When the melting or thermal decomposition temperature is less than 300°C, it has poor lubricity, probably because it burns out.

The aromatic hydrocarbon must have two or more carboxyl groups and alkali metal salts are preferred because of their uniform solubility or dispersibility in water and the uniformity of the film. As the alkali metals, sodium, potassium, and lithium are preferred. can give. Aromatic hydrocarbon alkali metal salts that have two or more carboxyl groups and a melting or thermal decomposition temperature of 300°C or higher are less than 0.2% by weight due to insufficient lubricity.
If it exceeds % by weight, the fluidity of the plastic material will deteriorate and neither is suitable.

The second component of the present invention, a water-soluble adhesion promoter, is polyvinylpyrrolidone, ammonium starch phosphate, sodium starch phosphate,
Examples include lithium starch phosphate, trialkylammonium hydroxyl alkyl ether starch (for example, Petrocise-J, manufactured by Nippon Star Chemical Co., Ltd.), and the like.

The reason why these materials have superior adhesion and lubricity compared to raw starch, gelatin, casein, which are said to be natural water-soluble polymers, and carboxylmethyl cellulose, hydroxyethyl cellulose, which are cellulose-based semi-natural polymers, is that Although it is not certain, it is thought that this is not simply a thickening effect of water, but is caused by the fact that the molecule contains nitrogen or phosphorus elements. If the water-soluble adhesion improver is less than 0.05% by weight, the adhesion and lubricity will be insufficient, and if it exceeds 20% by weight, the fluidity of the composition will be poor and neither is suitable.

[0013] The third component of the present invention has 10 carbon atoms.
In the alkanedioic acid alkali metal salts of 1 to 16, the alkali metals include sodium, potassium, and lithium. Alkanedioic acids having 10 to 16 carbon atoms are particularly dodecanedioic acid,
Tetradecanedioic acid is preferred. The addition of this component improves lubricity, and although the reason for this is not clear, it is thought that it has the effect of making the film formed on the tool surface more uniform and stronger. The amount of the alkali metal salt of alkanedioic acid having 10 to 16 carbon atoms is most preferably 0.2 to 5% by weight, and lubricity is insufficient if it is less than 0.2% by weight or more than 5% by weight.

The fourth component of the present invention, the surfactant, includes all surfactants that are transparently dissolved or dispersed in water and do not adversely affect adhesion and lubricity. Preferably, Japanese Patent Publication No. 63-2319, Japanese Patent Publication No. 62-1
Among the surfactants described in Japanese Patent Application No. 1799 and Japanese Patent Application No. 01-134325, those having a molecular weight of 1,000 to 1,
000,000 and containing a phosphate ion in the molecule, but more preferably the following formula 1

[Formula 1] L=H or CH3 M=alkylene oxide l=1 to 100 R1=H or C1-24 alkyl group or alkenyl group X=H, Na or K R2=H or C1-24 alkyl group m= 0-6 n=1-6 and chemical formula 2

[Chemical formula 2] R1 = H or CH3 R2 = H, CH3 or C2H5 X=H, Na
or K m=1~6 n=0~6

[0015] Molecular weight is 10,000 to 300,00
0 is a copolymer having a molecular structure represented by the above formula (I) or formula (II) to which 0.3 to 1.5 moles of phosphate ions are added per mole of the nitrogen-containing group. I can do it. This is a surfactant and high molecular weight dispersant that can be dissolved or dispersed in water.

In other words, the surfactant used in the present invention is an aromatic hydrocarbon alkali metal salt, a water-soluble adhesion improver, and an alkanedioic acid alkali metal salt that is difficult to dissolve or disperse in water. This improves dispersibility and contributes to uniform adhesion. Among them, ammonium starch phosphate, sodium starch phosphate, lithium starch phosphate, and carbon number 10
It shows desirable effects in improving the dispersion and uniform adhesion of the alkane metal salts of ~16 alkanedioic acids. Surfactant is 0.5
If it is less than 15% by weight, the uniform dispersibility will be insufficient, and if it exceeds 15% by weight, the lubricity and fluidity of the composition will be insufficient, and neither is suitable.

[0017] In the method for producing a lubricant of the present invention, as a first step, an aromatic hydrocarbon alkali metal salt having two or more carboxyl groups may be dissolved or dispersed in water or hot water at 50 to 60°C. An equivalent amount of an aromatic hydrocarbon having two or more carboxyl groups may be added to the aqueous solution of the alkali metal hydroxide for neutralization. (This is called liquid A.)

001
8] In the second step, a separately prepared aqueous solution of a water-soluble adhesion improver is added to Solution A and mixed and stirred to make it uniform. Alternatively, a water-soluble adhesion improver may be gradually added to the A liquid to make it uniform. Further, a product is obtained by adding an alkanedioic acid alkali metal salt and a surfactant and mixing and stirring. Alternatively, the alkanedioic acid alkali metal salt may be used by adding an equivalent amount of the alkanedioic acid to an aqueous solution of the alkali metal oxide and neutralizing it by heating. still,
This method is an example and is not limited thereto. Preservatives, rust preventives, ion sequestering agents, etc. may also be added to the product. In particular, preservatives are necessary components for the storage stability of products. The thus obtained lubricating oil of the present invention is further used by spraying it as a 1 to 25% by weight aqueous solution or aqueous dispersion.

[Examples] Next, the present invention will be explained with reference to Examples and Comparative Examples. Examples 1 to 11, Comparative Examples 1 to 10 Tables 1 and 2
Examples 1-
Samples No. 11 and Comparative Examples 1 to 8 were made. These samples and for further comparison, commercially available non-graphite water-soluble warm forging oil (Comparative Example 9) and commercially available graphite-containing water-soluble warm forging oil (Comparative Example 10).
) samples were subjected to a performance test using the test method shown below, and the results are listed in Tables 1 and 2. Confirmation by performance test 1. Adhesion test (method) After polishing with #240 abrasive paper, hot work tool steel (diameter 65 mm x thickness 8 mm) was heated to the specified temperature (200, 250, 300°C). After confirming that the specified temperature has been reached, air spray the sample under the following conditions and measure the amount adhered to the hot work tool steel. Results are expressed in mg/cm2. (Lubrication conditions) ■ Lubrication amount (70 ml/min)
■ Distance between nozzle and tool (300mm) ■ Air pressure (3 kg/cm2) ■ Lubrication time (3
sec) 2. Lubricity test (method) Schwingungs Reib un
d Verschieiss Tester (SRV
The temperature of the tool (150 to 200
℃), temperature of workpiece (600 to 1200℃)
and seizure load (Hertz pressure 200Kg/mm
2), operate under the following test conditions and determine the friction coefficient by temperature. (Test conditions) ■ Test piece Ball (S
UJ-2) Diameter 10mm Cylinder (S45C) 24 x 7.85mm■
Load 100 N (Hertz pressure
222kg/mm2) ■ Sliding speed 36
0 mm/min. ■ Temperature
500, 800℃ ■ Time 1
sec *1 in Tables 1 and 2 is in formula (I)
L=H, M=ethylene oxide, R1=
CH3, l=10, R1=C12H25
, X=Na, m=1, n=2. This is a surfactant in which 1 mole of phosphate ion is added to a copolymer per 1 mole of nitrogen-containing groups.

[0019]

[Table 1]

[0020]

[Table 2]

[0021]

Effects of the Invention As explained above, the lubricating oil agent of the present invention contains a specific aromatic hydrocarbon alkali metal salt, a water-soluble adhesion improver, a specific alkanedioic acid alkali metal salt, and a surfactant. As is clear from Table 1, the lubricant dissolved and/or dispersed in water at a ratio of The graphite-containing water-soluble warm forging oil (Comparative Example 10) shows that it has good performance in both adhesion and lubricity. Therefore, it has been confirmed that the present invention provides a lubricant that does not pose a risk of ignition, does not pollute the working environment, and can extend the life of tools.

Claims (1)

[Claims] Claim 1: 0.2 to 40% by weight of an aromatic hydrocarbon alkali metal salt having two or more carboxyl groups and a melting or thermal decomposition temperature of 300°C or higher, and 0.05 to 20% by weight of a water-soluble adhesion improver. % by weight, 0.2 to 5% by weight of an alkali metal salt of an alkanedioic acid having 10 to 16 carbon atoms, and 0.5 to 15% by weight of a surfactant, dissolved and/or dispersed in water. A lubricant for plastic processing.