JPS6054355B2 - Lubricant for plastic working of steel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lubricant used in plastic working of steel, such as rolling, drawing, and forging.

As the performance required for a lubricant for plastic working of steel] 2) m
]l-R212)m]1-R2 12)m]l-C-O-R2 is 1. The coefficient of friction is small and machining power can be reduced.2
It prevents tool wear and seizure between the tool and the material and extends the tool life. 3. It does not lose its lubrication performance when used under high temperature and high pressure conditions. 4. It does not inhibit tool cooling. It will be done.

On the other hand, conventionally used lubricants include mineral oils such as machine oil, natural oils and fats such as beef tallow and rapeseed oil, monoesters such as octyl palmitate, and fatty acids such as oleic acid, stearic acid, and dimer acid. Among them, beef tallow and rapeseed oil have excellent heat resistance and seizure resistance, and have a low coefficient of friction.
It is widely used in combination with fatty acids, etc.

However, recent developments in plastic working technology have made complex processing possible while significantly increasing processing speeds and requiring particularly stringent performance from lubricants.

Furthermore, efforts have been made to reduce power costs in order to promote resource and energy conservation, and in response to this trend, there has been a demand for lubricants with even lower coefficients of friction. Beef tallow and rapeseed oil are no longer sufficient to meet these demands, and when used under severe conditions such as high-speed machining, there is a risk of frequent seizing between the tool and the material. Therefore, the present inventors planned to develop a chemical compound of higher quality to replace natural fats and oils such as beef tallow and rapeseed oil, and as a result of systematically examining the structure of a large number of ester compounds and the number of carbon atoms of alcohols and fatty acids, We have succeeded in developing three types of synthetic esters that can be used in lubricants and have a low coefficient of friction and can withstand use under harsh conditions.

The gist of the present invention is a lubricant containing one or more of the above three synthetic esters represented by the following general formula.

However, R1: an alkyl group having 5 to 36 carbon atoms R2:
Alkyl group having 1 to 36 carbon atoms or H1
1: an integer of 1 to 5 N, m: an integer of 1 to 25 Here, the reason why the number of carbon atoms in R1 is set to 5 or more is because if it is less than 5, sufficient heat resistance cannot be obtained when used as a lubricating oil. This is because there is a risk of reducing lubricity due to frictional heat during machining.

Furthermore, when the number of carbon atoms in Rl and R2 exceeds 36, the compound becomes a polymer, increases the melting point, and becomes solid at room temperature, making it difficult to apply the lubricant uniformly. Uneven application of lubricant is caused by baking.
This is undesirable because it causes For the same reason, 1 is limited to 5 or less, and N and m are limited to 25 or less. Examples of the synthetic esters represented by the above general formulas (1), (■), and (■) include those shown in Table 1. These synthetic esters can be used individually to exhibit sufficient lubricity, seizure resistance, and heat resistance, but they can also be used as a mixture of two or more, and they can also be used in various conventional lubricants. Its performance can be significantly improved.

In this case, adding an emulsifier such as a nonionic surfactant will ionize the lubricant and make it easier to use, and if necessary, additives such as antioxidants, rust preventives, polar additives, etc. It will be done.

The performance test results of the lubricant of the present invention are shown in Table 2 in comparison with the conventional lubricant.

Test agents A, b, and c in Table 2 are synthetic esters 1, 5, and 9 shown in Table 1, respectively, and d is a mixture of 2 and 6, and E, f, and g are 1, 5, and 9 are mixed with conventional lubricants, and H, i, j, and k are 7 and 1.
This is a mixture of 1, 8, 1013, 4, 2, 7, and 12 mixed with conventional lubricants and additives.

The friction coefficient and seizure resistance were measured using a Bauden tester, and the heat resistance was measured using a thermobalance.

゛〈Test using Bauden testing machine〉 Various test agents were attached to the surface of a low carbon steel plate, and a steel ball with a diameter of 3116 inches was pressed against the attached surface with a load of 3k9 (Hertzian pressure 223k9/d) at a speed of 4? /Sec, and the friction coefficient of the attachment and the number of sliding movements until the friction coefficient reached 0.15 (seizure resistance) were measured.

<Test using thermobalance> 35Tn9 of the test material was placed in a platinum crucible and heated at a rate of 5°C per minute in a He atmosphere until the test material in the crucible reached 1
The heating temperature at the time of 00% decomposition and burning was measured.

In the Bauden test, in order to be as close as possible to actual plastic working conditions, the test temperature was set to 200'C in consideration of heat generation due to plastic deformation, and a mild steel plate that is easily plastically deformed was used.

The friction coefficient corresponds to the power required during actual machining, and the seizure resistance corresponds to the occurrence of seizure defects and tool life.

Furthermore, in a test using a thermobalance, it can be said that the higher the burnout temperature of the test material, the better the heat resistance.

As shown in the test results in Table 2, the lubricant of the present invention has significantly superior seizure resistance compared to beef tallow, which has the highest performance among conventional lubricants, and also has superior friction coefficient and heat resistance. The performance is equivalent to or better than that.

Therefore, by using the lubricant of the present invention, sufficient lubrication is guaranteed even under severe conditions such as high-speed machining, and machining becomes smoother and more efficient.

2. Product quality deterioration caused by insufficient lubrication, such as seizure defects, can be prevented, and tool wear and breakage can also be prevented, improving product quality and greatly extending tool life.

3. The power required during processing is reduced, further promoting resource and energy conservation.

It produces many excellent effects such as.

Claims (1)

[Claims] 1 The general formula is (I) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (II) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (III) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ However R_1: Alkyl group having 5 to 36 carbon atoms R_2: Alkyl group having 1 to 36 carbon atoms or H 1: An integer of 1 to 5 n, m: One or two esters represented by an integer of 1 to 25 A lubricant for plastic working of steel that contains more than