JPH0633393B2 - Water-soluble lubricant for plastic working - Google Patents

Description

The present invention relates to a water-soluble lubricant for plastic working. This lubricant can be plastically worked, i.e. forged, extruded, rolled, pressed,
Used in place of graphite-based lubricants for the purpose of mold release during metal working such as wire drawing, and especially for hot or warm forging or hot-extrusion metal working using graphite lubricant It is useful as a non-graphite lubricant.

[Prior Art] Oil-dispersed or water-dispersed graphite is usually used as a lubricant for plastic working of metals. The former is one in which graphite is dispersed in a mixture of mineral oil with extreme pressure additives, waxes, etc., but since most of the processing is performed hot, there is a risk of ignition and smoking, There are major problems in work environment and health. In the latter, graphite is dispersed by adding an extreme pressure additive to water. The lubricity is the same as that of the former oil dispersion, there is no problem of flammability, and the workability is slightly improved, but as long as graphite is used, it will pollute the worker and the work environment black. There is no change and health problems remain.

In order to solve these problems in the working environment, attempts have been made to develop a lubricant for plastic working that does not use graphite. For example, a lubricant in which a glass composition is contained in an alkali metal salt of aromatic carboxylic acid (JP-A-60-1293) or a lubricant in which an alkali metal salt of phthalic acid is used (JP-A-58-84898)
And so on. However, even in the case of these lubricants, in the former case, the glass composition is apt to be deposited in the concave portion of the mold and is likely to cause lack of wall thickness, and good lubricity cannot be obtained when the temperature of the mold is low. However, there are problems that the mold cannot be easily washed with water, and that spraying the glass composition is not good for the health of the worker. In addition, the latter has low toxicity, there are no particular health problems, and it has the good point that the mold can be easily washed with water.
It is confirmed that the lubricity is slightly inferior to that of graphite and that seizure is likely to occur in use.

[Problems to be Solved by the Invention]

As a lubricant for plastic working, a lubricant mainly composed of graphite is used as a main agent, and as described above, it contaminates the worker or the working environment in black, and it is considered that the lubricant has an adverse effect on health. In the case of, there is a problem that there is a risk of ignition.

Therefore, it has good lubricity, no pollution, does not catch fire,
There is a need for a lubricant that is easy to clean and does not cause health concerns. Further, the lubricant is generally used by diluting it with water, but it is required to have a predetermined performance even at a high dilution.

An object of the present invention is to provide a lubricant for plastic working that can satisfy such requirements.

[Means for Solving the Problems]

The present invention provides an alkali metal salt of an alicyclic hydrocarbon dibasic acid or a mixture of the alkali metal salt of a dibasic acid and an alkali metal salt of fumaric acid in an amount of 0.1 to 30% by weight, and a water-soluble compound 0.01 Provided is a water-soluble lubricant for plastic working, which comprises an aqueous composition containing 20% by weight.

The lubricant of the present invention may further contain, as an additive, an additive selected from an extreme pressure additive, a bactericide, a corrosion inhibitor, and a foam control agent.

Lubricant for plastic working, especially hot forging, has a mold temperature of about
Since it is a high temperature of 300 ° C, it cannot be used if it decomposes and disappears at temperatures around this, while it has physical properties as a lubricant, but it disappears while it is in contact with the metal to be forged at 1000 ° C or higher. Is desirable.

In this respect, graphite is useful, but an alkali metal salt of a dibasic acid is mentioned as a white one having similar properties. Here, metal soaps, that is, metal salts of saturated fatty acids which are monobasic acids are often used as lubricants for plastics, but these are not useful as lubricants for plastic working because they cannot be applied uniformly. .

Examples of the dibasic acid include saturated fatty acids such as succinic acid and adipic acid, unsaturated fatty acids such as fumaric acid and maleic acid, and aromatic carboxylic acids such as phthalic acid and isophthalic acid, and their alkali metal salts. When used as the main component of the lubricant for the purpose of the present invention, there is a problem that the friction coefficient is small, and therefore, it is easy for seizure to occur despite lack of wall thickness, or conversely, no seizure occurs but is likely to cause wall loss. Yes, the results are not satisfactory. However, by using the alkali metal salt of dibasic acid of alicyclic hydrocarbon alone or in combination with the alkali metal salt of fumaric acid, the above problems are completely eliminated, and good results are obtained. Was found to bring about.

Examples of the alicyclic hydrocarbon dibasic acid that can be used here include cyclohexanedicarboxylic acid such as hexahydrophthalic acid, hexahydroisophthalic acid and hexahydroterephthalic acid, tetrahydrophthalic acid, tetrahydroisophthalic acid, tetrahydroterephthalic acid. Examples thereof include cyclohexene dicarboxylic acid such as acid, cyclohexadiene dicarboxylic acid, and bicyclohexi dicarboxylic acid.

The use of these alkali metal salts of dibasic acids is for obtaining thermal stability, and especially for obtaining water solubility as a product, it is difficult to use alkaline earth metal salts. As the alkali metal salt, sodium salt, potassium salt and lithium salt are preferable, but sodium salt is particularly preferable.

The alkali metal salt of dibasic acid or a mixture thereof with the alkali metal salt of fumaric acid is contained as a lubricant main component in an amount of 0.1 to 30% by weight, preferably 5 to 15% by weight in the composition. It must be. If it is less than 0.1% by weight, the low coefficient of friction required as a lubricant cannot be obtained.
This is because a stable product state cannot be obtained when it exceeds the weight percentage. Further, the weight composition ratio of the alkali metal salt of an alicyclic hydrocarbon dibasic acid and the alkali metal salt of fumaric acid is:
It is desirable that it is from 10: 0 to 1: 9, preferably from 10: 0 to 3: 7.

The lubricant is generally spray applied to the mold by spraying. At this time, it is possible to apply only the lubricant main agent, but a water-soluble polymer compound is used as an adhesive agent for depositing a more uniform film. Examples of the water-soluble polymer compound include hydroxyethyl cellulose, carboxymethyl cellulose, sodium polycarboxylate, ammonium polycarboxylate and the like. The amount of the water-soluble polymer compound added is 0.01 to 20% by weight, preferably 0.1 to 5% by weight. This is 0.01% by weight
If it is less than 20% by weight, the effect as an adhesive cannot be obtained, and if it exceeds 20% by weight, the viscosity is remarkably increased and handling as a product becomes complicated.

The above composition can be sufficiently used as a lubricant for plastic working, but when working is performed under more severe operating conditions, there is a possibility that seizure may occur. A pressure additive may be added. Further, it is possible to add a bactericide for the purpose of preserving, a corrosion inhibitor for the purpose of preventing rust, and an antifoaming agent for suppressing foaming during spraying.

The water-soluble lubricant for plastic working of the present invention may be used as a stock solution, but is preferably 10 times to 50 times depending on the situation.
Dilute twice and use. From the viewpoint of performance, it is important that the amount of solid content applied is appropriate, and it is possible to increase or decrease the amount of application by increasing the dilution ratio, but due to restrictions such as the timing of application and processing and the nozzle shape, It is preferable to change the coating amount of the lubricant solid content by adjusting the dilution ratio. The compositional concentration described above is customarily the concentration before dilution. Any method may be used for coating the mold, but spraying is generally preferable.
Further, as the lubricant for plastic working, hot forging or other forging conditions or extrusion may be used.

〔The invention's effect〕

By using the composition of the present invention as a lubricant for plastic working, it is possible to obtain a lubricating performance and releasability that are superior to those of graphite, and since it is a white product, there is no pollution of the working environment and it is possible to maintain the health of workers. Is also excellent, and the problem of cleanability is eliminated.

〔Example〕

Next, the present invention will be further described with reference to examples. Parts and% in the examples are based on weight unless otherwise specified.

Example 1 The friction coefficient was determined by a ring compression experiment.

φ120 x 50 mm mold (SKD61, quenching), one each above and below
10 ml of lubricant, which was heated to 270 ° C and diluted 30 times, was spray-applied to the surface of the upper and lower molds in contact with the ring (pressure 5 kg
/ Cm ² ) On the other hand, φ60 × φ30 × 15mm ring (S45C
Material) is heated to 1000 ° C. in an electric furnace in an Ar atmosphere. The reduction rate of the height of the die and ring (working degree) and the rate of change of the inner diameter are calculated by the "Kudo energy method" (Proc. 5th.
The coefficient of friction was determined by plotting on the theoretical curve determined by g.Appl.Mech, (1955), 75). For comparison, the case where the amount of lubricant applied to the mold was diluted 50 times (50 ml) (10 times the solid amount of the above applied amount) was also used.

~ Lubricant compositions - (Examples 2 and 3 also similar composition) dibasic acid 11.0 parts 7.5 part of hydroxyethylcellulose, 2.0 parts of sodium hydroxide Haromakemu SK-7 fine amount water balance section 100.0 parts used in the experiments The results are shown in Table 1 below.

As a result of the ring compression test, the sodium salt of alicyclic dicarboxylic acid and a preferable blended composition thereof with sodium salt of fumaric acid showed a low friction coefficient, and particularly, a good friction coefficient even at a high dilution ratio. .

Example 2 The presence or absence of seizure was confirmed by a backward extrusion experiment. φ3
Punch type (SKD61, quenching) with 8 mm and draft angle of 1 °
Heat to about 300 ° C, and apply 10 times diluted lubricant by automatic spraying (4 kg / cm ² , ² m 1 / sec) for 0.3 sec x 4 times (2.4 ml in total, but with a lot of loss). On the other hand, φ
A 36.5 x 50 mm test piece (S45C material) is heated to 1000 ° C in an electric furnace in an Ar atmosphere. Punch type and test piece are set in 120ton hydraulic press and compressed. The same operation is repeated by changing the test piece, and the test piece is observed 5 times after completion. Even when the test piece and the punch die were seized, the device was devised so that they could be separated when pulled out. For comparison, the lubricant is applied to the punch type by hand spraying with a 5 times diluted solution of 5 ml (the solid content is 4 times the above applied amount, but there is practically no loss and more than that. It was also carried out when applied.

The results are shown in Table 2 below.

With the sodium salt of fumaric acid alone, vertical defects due to baking occurred in the punched R portion. However, baking did not occur with the sodium salt of alicyclic dicarboxylic acid and the preferred blends thereof with the sodium salt of fumaric acid.

Example 3 An evaluation was performed using an actual machine.

Hot forging of automobile parts (material S45C) was performed with a 1600 ton press and a 6000 ton press (material temperature about 1250).
℃, mold temperature about 350-400 ℃). The spray used is an airless automatic sprayer with a pressure of 5 kg / cm ² , and sprays for about 2 to 3 seconds while the mold is open. The dilution ratio is 30 times.

The results are shown in Table 3 below.

As a result of the actual machine evaluation, the lubricant of the present invention (No.
2,5,8,10) are more lubricious, releasable, and
It was confirmed that it has excellent performance in terms of seizure resistance, and that the workability therefor is also improved.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location C10M 145: 40) C10N 10:02 40:24 Z 8217-4H (72) Inventor ▲ Yoshi ▼ gawa Yasuhiro 73-36 Kibe Shinbo, Sakai-cho, Sakai-gun, Fukui Prefecture (72) Inventor Takashi Kojima 1-23, Hinata-cho, Mizuho-ku, Nagoya-shi, Aichi (72) Inventor Akihiro Oda 81-204, Maeda, Tendou, Inuyama-shi, Aichi

Claims (1)

[Claims] 1. A water-soluble polymer comprising 0.1 to 30% by weight of an alkali metal salt of an alicyclic hydrocarbon dibasic acid or a mixture of an alkali metal salt of the dibasic acid and an alkali metal salt of fumaric acid. A water-soluble lubricant for plastic working comprising an aqueous composition containing 0.01 to 20% by weight of a compound.