JP2004182879A - High performance water-soluble metal working fluid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water-soluble metal working fluid containing a fine powder of boron nitride having a crystalline turbostratic structure which has excellent dispersibility and lubricity as a substitute of heavy metals such as molybdenum disulfide. <P>SOLUTION: To provide a water-soluble metal working fluid having an improved dispersibility and emulsion stability by emulsifying in a water phase an oil phase which is prepared by dispersing an effective amount of boron nitride fine powder having a crystalline turbostratic structure in a base oil using an emulsifier, thus the fine powder of boron nitride is dispersion emulsified in a state of a fine grain and kept from sedimentation. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【表２】高性能水溶性金属加工油剤Ｎｏ．２の組成

【表３】高性能水溶性金属加工油剤Ｎｏ．３の組成

【００５２】
［実施例３］切削テスト１
試験条件は、
（１）使用機械：森精機製縦型マシニングセンター（ＭＶ−４０Ａ）
（２）被削材：ＡＣ８Ｂ−Ｔ６
（３）工具：ＯＳＧ製ニューロールタップＢ−ＮＲＴ Ｍ６×１．０ＲＨ７ Ｂ
（４）切削速度：１０ｍ／分
（５）下穴：φ５．４８×３０ｍｍ（リーマ仕上げ、止まり穴、引っかかり率１００％）
（６）切削長：２０ｍｍ
（７）水溶性切削油剤濃度：１０％
（８）加工数：５回
で、市販の水溶性切削油剤Ａと、表１の高性能水溶性金属加工油剤Ｎｏ．１とで、トルク評価による比較試験を行った。ただし、切削油剤は下穴に入れただけで行った。結果、高性能水溶性金属加工油剤Ｎｏ．１が市販の水溶性切削油剤Ａより、１５％低いトルクで切削加工できることが確認された。
【００５３】
［実施例４］切削テスト２
試験条件は、
（１）使用機械：やまわエンジニアリング取扱の精密タッビングマシン（メガタップＩＩ−Ｇ８）
（２）被削材：ＡＣ４Ｂ
（３）工具：ＯＳＧ製ニューロールタップＢ−ＮＲＴ Ｍ６×１．０ＲＨ７ Ｂ
（４）切削速度：１０ｍ／分
（５）下穴：φ５．５０±０．０５×２５ｍｍ（止まり穴）、
（６）切削長：１５ｍｍ
（７）水溶性切削油剤希釈倍率：１０倍、２０倍、５０倍、１００倍
（８）加工数：２０回
で、市販の水溶性切削油剤Ｂと、表２の高性能水溶性金属加工油剤Ｎｏ．２とで、トルク評価による比較試験を行った。ただし、切削油剤は下穴に入れただけで行った。結果は以下に示した表４の通りで、高性能水溶性金属加工油剤Ｎｏ．２は市販の水溶性切削油剤Ｂと比較して、高い希釈倍率での切削性能が高く、２倍以上の希釈で使用できることが分かった。
【００５４】
【表４】

【００５５】
［実施例５］切削テスト３
試験条件は、
（１）使用機械：ＲＯＫＵ−ＲＯＫＵ ＳＡＮＧＹＯ製マシニングセンターＭＩＮＩＭＡＣ−ＶＡ
（２）被削材：チタン合金（硬度ＨＲＣ４７〜４８、寸法１９７×３６５×４０ｍｍ）
（３）工具：日立ツールＥｐｏｃｈ２１ ＣＥＰＵ４１００ユニバーサル（ＣＥＰＵ超硬エポックユニバーサルエンドミル）の再研磨品で超硬の表面処理は無し
（４）切削速度：回転数２０００ｒｐｍ、送り２００ｍｍ／分
（５）切削深さ：１．５ｍｍ
（６）切削油剤：被削材平面を上向きにして、長手方向両端をマシニングセンターに固定し、固定箇所側３０ｍｍ前後を避けて、樹脂で４周囲に、高さ４０ｍｍ程度の壁を設け、内側に切削油剤を流し込んで試験を行った。
（７）切削パターン：右奥にある半円の凹み部分にエンドミルを落とし、▲１▼左に１８０ｍｍ切削、手前側へ１０ｍｍ切削、▲２▼右へ１６０ｍｍ切削、手前側へ１０ｍｍ切削、左へ１６０ｍｍ切削、手前側へ１０ｍｍ切削、▲３▼▲２▼をさらに２回繰り返す、▲４▼右へ１８０ｍｍ切削、奥へ７０ｍｍ切削。合計１４６０ｍｍを切削。
（８）水溶性切削油剤希釈倍率：最初の２６０ｍｍを５倍希釈、残りを３倍希釈で、表３の高性能水溶性金属加工油剤Ｎｏ．３を使って切削試験を行った。
【００５６】
従来、このような難削材は水溶性の切削油剤では切削できず、消火器を置いて、油性の切削油剤を使い、回転を落とし、送り２０〜５０ｍｍ／分程度で行われるが、本発明の高性能水溶性金属加工油剤Ｎｏ．３を使用すると、火災の心配のない水溶性で、しかも高速で切削加工できることが確認できた。また切削油剤の希釈倍率を落とすと、即ち切削油剤を濃くすると、切削面が滑らかになることも確認できた。試験後に刃先を確認したが、減りや偏摩耗等は全く認められなかった。
【００５７】
【発明の効果】
本発明の水溶性金属加工油剤は、窒化硼素微粉末が微粒子状に分散、乳化されているため窒化硼素の沈降が抑えられ、性能が安定し、水溶性であるため火災対策上も好ましい切削、研削油剤が得られる。窒化硼素の固体潤滑作用と、水の冷却作用とにより、優れた切削性能と工具の耐磨耗性能を発揮し、特に、結晶性乱層構造の窒化硼素の配合を調整することにより、チタン合金やインコネル等の重切削の分野で使用することも可能である。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a water-soluble metal working oil which can be widely applied to metal working such as cutting, grinding and plastic working, and more particularly to a water-soluble metal working oil which exhibits excellent effects with improved lubricating performance. It is.
[0002]
[Prior art]
Cutting fluids widely used in the cutting and grinding fields include water-insoluble cutting fluids based on mineral oil and water-soluble cutting fluids that contain mineral oil, surfactants, organic amines, etc., and are diluted with water for use. There is. A compound called an extreme pressure additive may be added to these cutting fluids in order to improve the lubricating performance of the fluid (for example, see Patent Document 1).
[0003]
Representative compounds of this extreme pressure additive include chlorine-containing compounds, sulfur-containing compounds, molybdenum-containing compounds, and the like. Metalworking oils generate waste oil after use, so for example, if the waste oil is burned, it will cause damage to the incinerator due to generation of chlorine gas, hydrogen chloride gas, sulfur oxide gas, etc., and shorten its life . Also, generation of dioxin has been observed in some chlorine-based additives. On the other hand, molybdenum compounds are subject to the PRTR law and require strict management.
[0004]
These extreme pressure additives are indispensable compounds in order to improve the lubrication performance of oils, but from the viewpoint of saving global resources and preventing global environment deterioration in recent years, they do not pollute the global environment more than before. There is a demand for the development of oil agents and, moreover, oil agents that extend the life of tools and the like as much as possible.
[0005]
In order to solve such a problem, the present inventors have already developed a high-performance lubricating oil in which an effective amount of boron nitride fine powder is dispersed and contained in a liquid component (for example, see Patent Document 2). It has been confirmed that these lubricating oils exhibit excellent performance for cutting, grinding and / or polishing due to the effect of boron nitride contained therein, but when used as a water-insoluble cutting oil, Water-soluble cutting oil is often used for fire prevention in large-scale facilities that exhibit excellent effects but have a risk of ignition and require a large amount of oil. On the other hand, when boron nitride is used as an extreme pressure agent in a cutting fluid, it has many features in terms of cost and work efficiency, such as longer tool life and increased cutting speed, but it is a solid and dissolves in the cutting fluid. In addition, since the specific gravity is as large as about 2.27, there is a problem in that when the powder is directly dispersed in a cutting fluid and used, it is settled. Further, a water-dispersion type plastic working lubricant containing an inorganic solid lubricant has been reported (for example, see Patent Document 3). However, lubrication during plastic working such as forging, rolling, wire drawing, and extrusion has been reported. It is limited to oil, and the size of the oil droplets is intended to be considerably large, as little as 50 μm or more, at least 5 μm or less, as estimated from the particle size of the solid lubricant used. On the other hand, in metal processing such as cutting, grinding, and polishing, finer particles are preferable in terms of performance, and the particle size of oil droplets of a water-soluble cutting oil called a general emulsion type is 2 to 5 μm. Considering the use of a filtration device for recirculation, it is desirable to set the thickness to 5 μm or less, but this is not applicable. Accordingly, there is a need for a high performance metalworking lubricant which is water soluble and has good boron nitride dispersibility.
[0006]
[Patent Document 1]
JP-A-11-166190
[Patent Document 2]
Japanese Patent No. 2911113
[Patent Document 3]
JP-A-10-316989
[0007]
[Problems to be solved by the invention]
Accordingly, an object of the present invention is to provide an environmentally friendly water-soluble metalworking oil that does not contain heavy metals such as molybdenum disulfide and does not generate harmful substances such as dioxin during disposal.
[0008]
Also, it solves the problem that the boron nitride fine powder used as an extreme pressure agent agglomerates and settles out. An object of the present invention is to provide a water-soluble metalworking oil.
[0009]
[Means for Solving the Problems]
The present invention has been made to solve the above-mentioned problems, and a fine powder of boron nitride as an extreme pressure agent contained in a water-soluble metalworking oil, particularly, a boron nitride having a crystalline turbostratic structure having excellent dispersibility and lubricity. The fine powder is dispersed in a base oil, the mixture is finely divided and emulsified in water to form an oil-in-water emulsion. The present inventors have found that by preventing agglomeration and confining the interface with oil in the interface, the sedimentation of the boron nitride fine powder can be suppressed by the buoyancy of the oil, and the present invention has been completed.
[0010]
That is, from the first viewpoint, the water-soluble metalworking oil of the present invention is obtained by emulsifying an oil system obtained by dispersing an effective amount of boron nitride fine powder having a crystalline turbostratic structure in a base oil, into an aqueous system using an emulsifier. Wherein the boron nitride fine powder is dispersed and emulsified into fine particles to suppress sedimentation, thereby having improved dispersibility and emulsion stability. In a second aspect, the water-soluble metalworking fluid of the present invention contains an effective amount of fine boron nitride powder having a hexagonal system and / or a crystalline turbostratic structure having an average primary particle size of 1 μm or less in a base oil. The oil system is characterized in that the oil system is emulsified in an aqueous system by using an emulsifier, and the boron nitride fine powder is dispersed and emulsified into fine particles to improve sedimentation. Has dispersibility and emulsion stability.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
As the lubricating base oil constituting the water-soluble metalworking oil agent of the present invention, mineral oil, synthetic oil, animal and vegetable oil, or a mixture thereof can be used. The mineral oil, synthetic oil, and animal and vegetable oils are not particularly limited as long as they are generally used as base oils for metalworking oils. As the mineral oil, for example, a refined mineral oil of ISO VG10 to ISO VG460 is preferable, and any of a paraffinic type and a naphthenic type may be used. On the other hand, as synthetic oils, polyol esters, polyglycols, polyalphaolefins, alphaolefins, normal paraffins, isoparaffins, alkylbenzenes, polyethers, and the like can be used. Also, as animal and vegetable oils, beef tallow, rapeseed oil, soybean oil, sunflower oil, sunflower oil, castor oil, coconut oil, coconut shell oil and the like can be used. These base oils can be used alone or in combination of two or more, and mineral oil, synthetic oil, and animal and vegetable oils may be used in combination.
[0012]
The fine boron nitride powder constituting the water-soluble metalworking oil of the present invention is chemically stable compared to other solid lubricants such as graphite, and is characterized in that it is not oxidized to near 1000 ° C. in air. Boron nitride (BN) is a compound composed of boron and nitrogen, and boron nitride has a polymorph having substantially the same crystal structure as carbon. Amorphous boron nitride (hereinafter referred to as “a-BN”), Hexagonal boron nitride (hereinafter, referred to as “h-BN”) having a structure in which hexagonal mesh layers are stacked in a two-layer cycle, and rhombohedral crystal having a structure in which hexagonal mesh layers are stacked in a three-layer cycle. Boron nitride (hereinafter, referred to as “r-BN”), boron nitride having a turbostratic structure in which hexagonal mesh layers are randomly stacked (hereinafter, referred to as “t-BN”), and cubic boron nitride as a high-pressure phase (hereinafter, referred to as “t-BN”) Hereinafter, "c-BN" is known.
[0013]
It is known that h-BN crystals have the same cleavage properties as hexagonal graphite crystals and exhibit good solid lubricity. The origin of the lubricity of the h-BN crystal is the van der Afars bond, in which the bond between the two-dimensional hexagonal mesh layers is weak as in the case of graphite, showing remarkable cleavage properties in this plane and cleaved in a scaly manner between the layers. This is considered to be because the crystal particles have a property of slipping easily with each other.
[0014]
In the present invention, a two-dimensional crystal structure is developed, but the lamination state between layers does not develop as much as h-BN, and hexagonal mesh layers are randomly laminated to form crystalline boron nitride having a turbostratic structure. It is called sex t-BN. The characteristic structure of the crystalline t-BN can be defined by characteristic peaks obtained by measuring a powder X-ray diffraction pattern. For example, as shown in FIG. 2 of JP-A-10-203807. Having a diffraction pattern.
[0015]
The crystalline t-BN fine powder is heated in a reaction vessel in which a mixed raw material containing, for example, boric anhydride and urea (further as an optional component, an alkali borate such as sodium borate) is placed in a non-oxidizing atmosphere, and is heated to about 1100 ° C. (Preferably at 950 ° C. or lower) to generate a-BN, and then heat the reaction product at 1200 ° C. to 1500 ° C. (preferably 1200 to 1400 ° C., more preferably 1250 to 1350 ° C.) Crystallization of -BN to t-BN can be achieved in high yield. The obtained reaction product is purified by washing with water (preferably with hot water) (including acid washing if necessary), and excluding soluble components such as alkali and boron oxide, the average particle size of primary particles is 1 μm or less. Fine powder of crystalline t-BN can be produced in high yield and mass-produced at low cost. According to this synthesis method, the particle size of the primary particles can be changed by changing the temperature and time for crystallization, and it is possible to synthesize boron nitride powder in which h-BN and crystalline t-BN coexist. it can. This synthesizing method is described in detail in JP-A-10-203807, and the contents thereof are incorporated by reference in the present application as necessary.
[0016]
The crystalline t-BN synthesized and purified as described above is usually secondary particles in which fine primary particles having a particle size of 1 μm or less are aggregated, but if they are forcibly dispersed, most of them are primary particles. It can be a dispersion of fine crystalline t-BN fine powder. If necessary, dispersion may be performed using an attrition mill, a ball mill, or a roll type (including two or three type) shearing mill using ceramic beads or balls (such as zirconia) as grinding media. Fine primary particles having an average particle size of 1 μm or less (preferably 0.5 μm or less, more preferably 0.3 μm or less, and most preferably 0.1 μm or less), for example, by wet grinding or dry grinding such as a jet mill. Can be disintegrated and dissociated. This crystalline t-BN fine powder does not have hygroscopicity as seen in a-BN powder, is stable and has oxidation resistance. According to the above-mentioned production method, it is possible to provide a fine powder having a similar particle size distribution for h-BN, and it is possible to provide a crystalline boron nitride fine powder mainly composed of crystalline t-BN partially containing h-BN. Powder can also be mass-produced. That is, when the crystalline t-BN fine powder is heat-treated at 1450 ° C. or higher, conversion to h-BN starts, and the powder becomes a mixture of t-BN and h-BN. The fine boron nitride powder dispersed in the water-soluble metal working oil exhibits excellent lubricity when the proportion of the crystalline t-BN fine powder is large. In order to exhibit excellent lubricity, preferably 50% by weight or more (70% by weight or more, more preferably 80% by weight or more, more preferably 90% by weight or more) of the boron nitride fine powder contained in the water-soluble metalworking fluid. Is preferably a crystalline t-BN fine powder. The content ratio of the crystalline t-BN fine powder in the boron nitride fine powder is determined by the intensity (area of the diffraction line) of the diffraction line obtained by powder X-ray diffraction and the mixing ratio of the standard boron nitride fine powder having a known mixing ratio. It can be measured by comparing with the intensity of powder X-ray diffraction.
[0017]
Both the h-BN powder and the crystalline t-BN fine powder consist of crystal particles having cleavage properties, and the h-BN fine powder and the crystalline t-BN fine powder, particularly the crystalline t-BN fine powder, are excellent solids. Shows lubricity.
[0018]
The finer boron nitride fine powder of h-BN and crystalline t-BN exhibits a good lubricating effect even with a small amount of addition. For this reason, it is preferable that the average particle diameter of the boron nitride fine powder in the water-soluble metal working oil agent be 1 μm or less, including the secondary particles. If the boron nitride fine powder is pulverized with a mill or the like, the secondary particles can be relatively easily dispersed into a fine powder composed of fine primary particles.
[0019]
The mixing amount of the fine boron nitride powder in the water-soluble metalworking oil agent is appropriate and economical depending on the conditions of use, but since it can impart a good lubricating effect and can cover a wide range of lubricating conditions, It is preferable that the mixing amount of the fine boron nitride powder in the non-conductive metal working fluid is 0.1 to 35% by weight. The reason is that if the mixing amount is less than 0.1% by weight, the lubricating effect obtained is small, and if the mixing amount exceeds 35% by weight, it is difficult to uniformly disperse and the fluidity is impaired, so that good lubrication properties are exhibited. It becomes difficult. In order to exhibit lubricity with good cost performance, it is particularly preferable that the mixing amount of the fine boron nitride powder is 0.1 to 25% by weight.
[0020]
The crystalline t-BN fine powder in which the two-dimensional crystal structure has been developed has a substantially disk-shaped or substantially spherical primary particle shape, and has excellent lubrication performance. The shape of the primary particles can be observed with a photograph of a scanning electron microscope (SEM), for example, as shown in the SEM photograph of FIG. 5 of JP-A-10-203807. Since the addition of the crystalline t-BN fine powder can impart excellent lubricity to the water-soluble metal working oil, in the present invention, the primary particles of the boron nitride fine powder preferably contained in the water-soluble metal working oil are preferably used. 50% by weight or more, more preferably 70% by weight or more (most preferably substantially all) is substantially disk-shaped or substantially spherical. The reason that the primary particles of the crystalline t-BN fine powder do not form a hexagonal plate shape like the h-BN crystal particles is that the crystalline t-BN has a regularity in the lamination relation between the layers of the two-dimensional network layer. It is understood that it is because it does not have.
[0021]
As the emulsifier constituting the water-soluble metalworking oil agent of the present invention, an anionic surfactant, a nonionic surfactant, or a mixture thereof can be used. When a mineral oil is used as the lubricating base oil, the HLB (hydrophile-lipophile balance) of the emulsifier is preferably about 10 to 18, and more preferably 12 to 16. When a synthetic oil or animal or vegetable oil is used as the lubricating base oil or when the amount of the additive is large, the HLB may be different. The content of the emulsifier is preferably from 0.1 to 30% by weight, more preferably from 0.1 to 20% by weight, based on the whole composition.
[0022]
Examples of the anionic surfactant include: (1) soaps, rosin soaps, and alkyl ether carboxylate salts derived from natural beef tallow, coconut oil, and palm oil; and (2) linear alkylbenzene sulfonic acid. Salts, α-olefin sulfonates, dialkyl sulfosuccinates, sulfonates such as naphthalene sulfonates, (3) sulfates such as alkyl sulfates and alkyl ethersulfates, and (4) phosphates. There are acyl-N-methyltaurine salts and the like, and nonionic surfactants include (5) ester type such as glycerin fatty acid ester, sorbitan fatty acid ester, and sucrose fatty acid ester; and (6) polyoxyethylene alkyl ether. Polyethylene oxide in which some of the ethylene oxide in the components is replaced with propylene oxide Other nonionic surfactants, such as ethers such as kilphenyl ether and polyoxyethylene / polyoxypropylene glycol, (7) ester / ether type, (8) fatty acid alkanolamide type, alkyl polyglycoside, etc. However, surfactants are compatible with base oils and other additives, and emulsification may be unstable depending on the combination. Therefore, it is preferable to select and confirm surfactants as appropriate.
[0023]
The water-soluble metalworking oil agent of the present invention uses the above-described base oil, fine silicon nitride fine powder, and an emulsifier, and adds an oil system in which fine silicon nitride fine powder is dispersed and contained in the base oil to a water system. Fine particles are dispersed and emulsified by high-speed stirring using a stirring mixer such as a mixer, a homogenizer, or a colloid mill, preferably a homogenizer.
[0024]
Prior to the high-speed stirring, the finely divided shelf nitride powder is crushed and mixed with the base oil using various mills, mixers, homogenizers, and the like, and sufficiently finely and uniformly dispersed. Preferably, beforehand, if fine pulverized sulfur nitride is pulverized and mixed with a small amount of base oil in advance, collisions between fine pulverized silicon nitride powders increase, and finer pulverization can be performed. The oil droplets containing the dispersed and emulsified silicon nitride fine powder thus dispersed have an average particle diameter of 2 μm or less, preferably 1 μm or less. And at the same time exhibit more stable lubrication.
[0025]
Before the high-speed stirring, the emulsifier is also added to either the oil system or the water system in its entirety, or is added to both of these systems as appropriate, and mixed and stirred well. Preferably, the mixture is heated and stirred until the selected emulsifier is appropriately dissolved, generally at about 60 ° C. It is preferable to heat both the oil system and the water system regardless of the presence or absence of the emulsifier, because the emulsification becomes easier. After the emulsification, in order to stabilize the emulsified state, it is preferably forcibly cooled to near normal temperature.
[0026]
In a preferred embodiment of the present invention, an antioxidant, a viscosity index improver, a pour point depressant, an antiseptic, a rust preventive, an oiliness improver, and an extreme pressure additive are added to the oil system and / or the water system according to use conditions. Agents, defoamers and the like are added.
[0027]
When the additive is added to the oil system, if the additive is heated to about 60 ° C. and then added, the viscosity is reduced and the oil is easily handled. After the addition, the oil system is preferably heated to 60 ° C. and mixed, which is preferable because it is easily dispersed. It is preferable to add the additive after dispersing and containing fine silicon nitride fine powder in the base oil. This is because if the additives are added first, the disintegration of the fine silicon nitride fine powder is hindered, and it becomes difficult to remove agglomeration. When the additive is added to the aqueous system, it is preferable to knead the emulsion with a mixer or a homogenizer after the emulsified state is stabilized after cooling the emulsion. When adding before emulsification, it is necessary to confirm in advance that emulsion stability is not hindered. In addition, when an additive that is hardly soluble in water is added, it is necessary to take measures such as dissolving it in another water-soluble additive in advance and then adding it.
[0028]
Examples of the antioxidant include: (1) a phenolic radical scavenger of 2,6-ditert-butyl-para-cresol (DBPC); (2) an amine radical scavenger of phenyl-alpha-naphthylamine and dialkyldiphenylamine; (3) ZnDTP hydroperoxide decomposer, (4) Penzotriazole, zinc dialkyldithiophosphates, dialkylselenium, metal phenates, metal deactivators of organic nitrogen compounds and the like can be used.
[0029]
Examples of the viscosity index improver include polymethacrylate, polyacrylate, polyisobutylene, olefin (copolymer) copolymer, polyalkylstyrene, ethylene-propylene copolymer, and hydrogenated styrene-diene copolymer.
[0030]
Examples of the pour point depressant include (low molecular weight) polymethacrylate, polyacrylate, chlorinated paraffin-naphthalene condensate, chlorinated paraffin-phenol condensate, and polyalkylstyrene.
[0031]
As the above-mentioned putrefaction inhibitor, benzoisothiazoline compounds, triazine compounds, phenol compounds, formaldehyde donor compounds, salicylanilide compounds, and the like can be used.
[0032]
Examples of the rust preventive include: (1) a metal soap, a carboxylate of an amine salt, (2) a carboxylic acid of an alkenylsuccinic acid derivative, (3) a sulfonic acid salt of a metal sulfonate salt, and a dialkylnaphthalene sulfonate. (4) Oleic acid based on oleic acid and its salt, (5) Ester based sorbitan monooleate, (6) Phosphoric acid and phosphate based on alkylamine, acidic alkyl phosphate, dibutyl acid phosphate Etc. can be used.
[0033]
As the oiliness improver, higher fatty acids, higher alcohols, fatty acid amines, fatty acid amides, esters and the like can be used.
[0034]
Examples of the extreme pressure additives include: (1) sulfur-based materials such as olefin polysulfide, sulfurized oils and fats, and dibenzyl disulfide; (2) alkyl and allyl phosphates; alkyl and allyl subesters; amine salts of phosphates; Phosphorus compounds such as amine salts of esters and thiophosphate esters, and (3) organometallic compounds such as naphthenate salts can be used.
[0035]
As the antifoaming agent, silicone oil, silicone polymers, esters, polyhydric aliphatic alcohols, alkenylsuccinic acid derivatives, metal soaps, polyacrylates, acylated polyamides and the like can be used.
[0036]
In a further preferred embodiment of the present invention, there is provided a water-soluble metalworking oil containing the water-based amine, an oil-soluble amine, and a fatty acid. Examples of the water-soluble amine include triethanolamine, triisopropanolamine, methyldiethanolamine, dimethylethanolamine, monoisopropanolamine, 2-amino-2-methyl-1-propanol, 2- (2-aminoethoxy) ethanol, and diethyl. Monoisopropanolamine, N, N-dibutylaminoethanol, N, N-di-n-butylaminoisopropanol, N, N-di-n-propylaminoisopropanol, N, N-di-tert-butyldiethanolamine, N, N -Ethylenediamine (diisopropanol), N, N-ethylenediamine (diethanol), mono-n-butyldiethanolamine, monoethyldiisopropanolamine, etc., and other water-soluble amines or It may also contain an alkali.
[0037]
Specifically, one or two of triisopropanolamine and methyldiethanolamine and one or two of monoisopropanolamine, 2-amino-2-methyl-1-propanol and 2- (2-aminoethoxy) ethanol Combinations and the like.
[0038]
Examples of the fat-soluble amine include monocyclohexylamine, dicyclohexylamine, 1,3-bisaminomethylcyclohexane, metaxylenediamine, morpholine, laurylamine, and oleylamine.
[0039]
Examples of the fatty acids include linear and / or branched saturated and / or unsaturated fatty acids and / or dibasic acids. For example, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, undecanoic acid, dodecanoic acid, tridecane, pentadecanoic acid, heptadecanoic acid, nonadecanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, Behenic acid, isostearic acid, elaidic acid, oleic acid, linoleic acid, linoleic acid, hydroxylauric acid, hydroxymyristic acid, hydroxypalmitic acid, hydroxystearic acid, hydroxyarachinic acid, hydroxybehenic acid, ricinoleic acid, hydroxy Octadecenoic acid, sebacic acid, dodecandioic acid, dodecylsuccinic acid, laurylsuccinic acid, stearylsuccinic acid, isostearylsuccinic acid, dimer acid and the like. Examples of unsaturated fatty acids include, for example, heptenoic acid, octenoic acid, nonenic acid, decylenic acid, undecylenic acid, dodecylenic acid, tridecylenic acid, nonadecenoic acid, eicosenoic acid, isoheptenoic acid, isooctenoic acid, isononenoic acid, isodecylenic acid, isoundecilene Acid, indodecylenic acid, isotridecylenic acid, heptanedienoic acid, octanedienoic acid, nonandienoic acid, decanedienoic acid, undecandienoic acid, dodecanedienoic acid, tridecanedienoic acid, isoheptanedienoic acid, isooctanedienoic acid, isononanedienoic acid, isodecaneide Examples include dienoic acid, isoundecanedienoic acid, indodecanedienoic acid, isotridecanedienoic acid, and neodecenoic acid. In addition, fatty acids obtained from natural fats and oils such as animals, fish, plants, and grains may be used.
[0040]
【Example】
Hereinafter, the results of metal working tests performed using the high-performance water-soluble metal working oil of the present invention will be specifically described, but these examples are merely examples of the present invention and do not limit the present invention.
[0041]
[Example 1] Production of crystalline t-BN fine powder
3.5 kg of boric anhydride, 5.3 kg of urea, borax (Na ₂ B ₂ O ₃ ・ 10H ₂ O) A mixture capable of sealing 0.63 kg of a mixture is placed in a stainless steel pressure-resistant vessel of about 12 liters, heated to 900 ° C. in about 1 hour, and kept at 900 ° C. for about 10 minutes to complete the reaction. a-BN was synthesized. During this reaction, water and carbon dioxide are released from the reaction system and the pressure inside the reaction vessel rises, so that the inside of the reaction vessel was filled with a mixed gas of water and carbon dioxide higher than 1 atm. Next, the calm-baked reactant taken out of the reaction vessel was pulverized into particles of 1 mm or less, and the pulverized substance was placed in an alumina container with a lid, placed in an electric furnace in a nitrogen gas atmosphere, and placed at 1300 ° C. for 10 hours. The temperature was further raised to 1,300 ° C. for 2 hours to crystallize t-BN to obtain crystalline t-BN fine powder. At the time of this crystallization, sodium borate coexisting with a-BN serves to promote the conversion of a-BN to crystalline t-BN, so that crystalline t-BN fine powder can be synthesized in high yield. Since sodium borate and other impurities are attached to the sewn crystalline t-BN fine powder, the powder is washed with ion-exchanged water at about 80 ° C. and purified to obtain about 0.63 kg (yield in terms of boron of about 70%). Of crystalline t-BN fine powder was obtained.
[0042]
As a result of analyzing these crystalline t-BN fine powders using an X-ray diffractometer, characteristic peaks of crystalline t-BN were recognized, and the peaks are shown in FIGS. 2 and 7 of JP-A-10-203807. A typical example is shown.
[0043]
[Example 2] Preparation of high-performance water-soluble metalworking oil
A high performance water soluble metalworking fluid was prepared as follows. That is, No. 1 shown in Tables 1-3. Three types of high performance water-soluble metalworking oils of 1-3 were prepared. Raw materials were prepared by dividing into three types: oil-based, water-based, and soap.
[0044]
First, an oil system was prepared. Machine oil No. Separate 46 and t-BN into a container and use a homogenizer (manufactured by KINEMATICA AG, polytron low noise homogenizer, main body model number: PT6100, generator shaft model number: DA6050 / 2, but use DA6050 / 6 only during emulsification) The mixture was well stirred and mixed at 7000 rpm for 10 minutes.
[0045]
The remaining oil-based raw materials were added to the above mixture except for polyoxyethylene polyoxypropylene alkyl ether, which is a nonionic surfactant as an emulsifier, warmed to 60 ° C. in a water bath, and 7000 rpm using a homogenizer. And mixed well for 10 minutes.
[0046]
Polyoxyethylene polyoxypropylene alkyl ether was added to this mixture, warmed to 60 ° C. with hot water, and thoroughly stirred and mixed by hand using a glass rod.
[0047]
An aqueous preparation was performed in parallel. Water and polyoxyethylene polyoxypropylene alkyl ether were separately placed in a container, warmed to 60 ° C. in hot water, and thoroughly stirred and mixed by hand using a glass rod.
[0048]
The oil system prepared above was added to the aqueous system, and the mixture was thoroughly stirred, mixed, and emulsified at 7000 rpm for 3 minutes using a homogenizer. The emulsion was immersed in tap water in a container and cooled with stirring until the temperature became 30 ° C. or lower. After that, those without using soap were added with Silicon defoamer as they were, and stirred and mixed well at 7000 rpm for 3 minutes with a homogenizer.
[0049]
Separately, soap was prepared. The amount prepared was 856 g, which is larger than that required for the present preparation. The coconut oil fatty acid was dissolved in hot water and the required amount was set aside in containers. All the other raw materials were separated into containers, and were thoroughly stirred and mixed with a homogenizer at 7000 rpm for 10 minutes.
[0050]
A required amount of each of the soaps was added to the emulsion, and the mixture was thoroughly stirred and mixed with a homogenizer at 7000 rpm for 3 minutes. Thus, high-performance water-soluble metalworking oils having the compositions shown in Tables 1 to 3 were prepared. No. Regarding 1 and 2, when the particle size distribution of oil droplets was measured using a laser diffraction type particle size distribution analyzer (manufactured by Shimadzu Corporation, SALD-2000), the former had an average value of 0.624 μm and a standard deviation of 0.103 μm. The latter has an average value of 0.699 μm and a standard deviation of 0.094 μm, and when calculating the average value + 3σ, it can be seen from the fact that they are 0.933 μm and 0.981 μm, respectively. It was 1 μm or less.
[0051]
[Table 1] High-performance water-soluble metalworking oil No. Composition of 1

[Table 2] High-performance water-soluble metalworking oil No. Composition of 2

[Table 3] High-performance water-soluble metalworking oil No. Composition of 3

[0052]
[Example 3] Cutting test 1
The test conditions are
(1) Machine used: Mori Seiki vertical machining center (MV-40A)
(2) Work material: AC8B-T6
(3) Tool: OSG New Roll Tap B-NRT M6 × 1.0RH7 B
(4) Cutting speed: 10m / min
(5) Prepared hole: φ5.48 × 30 mm (reamed finish, blind hole, hooking rate 100%)
(6) Cutting length: 20mm
(7) Water-soluble cutting oil concentration: 10%
(8) Number of processing: 5 times
And a commercially available water-soluble cutting fluid A and a high-performance water-soluble metalworking fluid No. 1 and a comparative test by torque evaluation was performed. However, the cutting oil was simply placed in the pilot hole. As a result, the high-performance water-soluble metalworking oil No. It was confirmed that No. 1 can be cut with a torque 15% lower than that of a commercially available water-soluble cutting oil A.
[0053]
[Example 4] Cutting test 2
The test conditions are
(1) Machine used: Precision tapping machine handled by Yamawa Engineering (Mega Tap II-G8)
(2) Work material: AC4B
(3) Tool: OSG New Roll Tap B-NRT M6 × 1.0RH7 B
(4) Cutting speed: 10m / min
(5) pilot hole: φ5.50 ± 0.05 × 25mm (blind hole),
(6) Cutting length: 15mm
(7) Water-soluble cutting oil dilution ratio: 10 times, 20 times, 50 times, 100 times
(8) Number of processing: 20 times
And a commercially available water-soluble cutting oil B and a high-performance water-soluble metalworking oil No. 2 and a comparative test by torque evaluation was performed. However, the cutting oil was simply placed in the pilot hole. The results are as shown in Table 4 below, and the results are shown in Table 4. It was found that No. 2 had high cutting performance at a high dilution ratio as compared with commercially available water-soluble cutting fluid B, and could be used at a dilution of 2 times or more.
[0054]
[Table 4]

[0055]
[Example 5] Cutting test 3
The test conditions are
(1) Machine used: ROKU-ROKU SANGYO MINIMAC-VA machining center
(2) Work material: titanium alloy (hardness HRC 47-48, dimensions 197 × 365 × 40 mm)
(3) Tool: Hitachi Tool Epoch21 CEPU4100 Universal (CEPU Carbide Epoch Universal End Mill), no polished surface treatment
(4) Cutting speed: rotation speed 2000 rpm, feed 200 mm / min
(5) Cutting depth: 1.5mm
(6) Cutting fluid: With the work material plane facing upward, both ends in the longitudinal direction are fixed to the machining center, avoiding around 30 mm on the fixed point side, providing a resin around 4 and a wall with a height of about 40 mm around the fixing point side, and inside The test was performed by pouring a cutting fluid.
(7) Cutting pattern: Drop the end mill into the semicircular dent at the back right, (1) cut 180mm to the left, cut 10mm to the front, (2) cut 160mm to the right, cut 10mm to the front, left 160 mm cutting, 10 mm cutting to the near side, (3) and (2) are repeated twice more. (4) 180 mm cutting to the right and 70 mm cutting to the back. Cutting a total of 1460mm.
(8) Dilution ratio of water-soluble cutting fluid: The first 260 mm was diluted 5-fold, and the rest was diluted 3-fold. No. 3 was used to perform a cutting test.
[0056]
Conventionally, such a difficult-to-cut material cannot be cut with a water-soluble cutting fluid, but is placed at a fire extinguisher, using an oil-based cutting fluid, reduced in rotation, and fed at a feed rate of about 20 to 50 mm / min. High performance water-soluble metalworking oil No. It was confirmed that when No. 3 was used, it was water-soluble without fear of fire and could be cut at high speed. It was also confirmed that when the dilution ratio of the cutting fluid was reduced, that is, when the cutting fluid was made thicker, the cut surface became smooth. After the test, the cutting edge was confirmed, but no reduction or uneven wear was observed at all.
[0057]
【The invention's effect】
The water-soluble metalworking oil agent of the present invention is characterized in that boron nitride fine powder is dispersed and emulsified in fine particles, so that sedimentation of boron nitride is suppressed, and the performance is stable. A grinding oil is obtained. The solid lubricating action of boron nitride and the cooling action of water provide excellent cutting performance and tool wear resistance. In particular, by adjusting the composition of boron nitride having a crystalline turbostratic structure, titanium alloy And in the field of heavy cutting such as Inconel.

Claims (11)

An improved oil-based boron nitride powder, characterized in that the oil-based material in which an effective amount of a boron nitride fine powder having a crystalline turbostratic structure is dispersed in a base oil is emulsified in an aqueous system using an emulsifier. A water-soluble metalworking oil having dispersibility and emulsion stability. A form in which an effective amount of a hexagonal system having an average primary particle size of 1 μm or less and / or a finely divided boron nitride having a crystalline turbostratic structure dispersed in a base oil is dispersed in an aqueous system using an emulsifier. A water-soluble metalworking oil having improved dispersibility and emulsion stability of said boron nitride fine powder, characterized by comprising: The water-soluble metalworking fluid according to claim 2, wherein 50% by weight or more of the boron nitride fine powder is a boron nitride fine powder having a crystalline turbostratic structure. The water-soluble metalworking oil according to any one of claims 1 to 3, wherein the average particle diameter of primary particles of the boron nitride fine powder is 0.5 µm or less. The water-soluble metalworking oil according to any one of claims 1 to 4, wherein the content of the boron nitride fine powder is 0.1 to 25% by weight based on the total composition. The water-soluble metalworking oil according to any one of claims 1 to 5, wherein 50% by weight or more of the boron nitride fine powder is primary particles having an average particle diameter of 0.3 µm or less. The water-soluble metalworking oil according to any one of claims 1 to 6, wherein 50% by weight or more of the boron nitride fine powder observed by an electron microscope has a substantially spherical shape or a substantially disk shape. The water-soluble metalworking oil according to any one of claims 1 to 7, wherein the emulsifier is an anionic surfactant and / or a nonionic surfactant. The water-soluble metalworking oil according to any one of claims 1 to 8, wherein the content of the emulsifier is 0.1 to 20% by weight based on the total composition. The oil-based and / or water-based systems are selected from the group consisting of antioxidants, viscosity index improvers, pour point depressants, decay inhibitors, rust inhibitors, oiliness improvers, extreme pressure additives, and defoamers. The water-soluble metalworking oil according to any one of claims 1 to 9, wherein one or more kinds are added. The water-soluble metalworking oil according to any one of claims 1 to 10, wherein the aqueous system contains a water-soluble amine, an oil-soluble amine, and a fatty acid.