CFRP water-based cutting fluid and preparation method thereof

Abstract

This invention relates to the field of cutting fluid technology, and discloses a CFRP water-based cutting fluid and its preparation method. The CFRP water-based cutting fluid comprises, by mass percentage: 13-16% ester lubricant, 12-14% polyether lubricant, 3-5% organic base, 2-3% rust inhibitor, 4-6% surfactant, 0.4-0.5% complexing agent, 4-5% biological stabilizer, 0.4-0.6% metal deactivator, 0.1-0.3% defoamer, with the balance being deionized water. The CFRP water-based cutting fluid provided by this invention possesses excellent lubrication and cooling properties, can rapidly form a high-strength lubricating film, significantly reduces cutting force and frictional heat, and effectively inhibits delamination, tearing, and tool wear during CFRP machining; it also exhibits excellent resistance to swelling and chip dispersion, preventing material dimensional deviations and chip agglomeration.

Description

Technical Field

[0001] This invention relates to the field of cutting fluid technology, and in particular to a CFRP water-based cutting fluid and its preparation method. Background Technology

[0002] Carbon fiber reinforced polymer (CFRP) is an advanced composite material made by layering and curing high-strength carbon fiber as the reinforcing phase and corrosion-resistant epoxy resin as the matrix. It perfectly combines the high specific strength and high specific stiffness of carbon fiber with the fatigue resistance and designability of the resin matrix, and is hailed as a strategic new material for weight reduction and efficiency improvement. Currently, CFRP is widely used in aerospace (such as fuselages and wings), defense, high-end automobiles, and wind turbine blades, and its usage has become one of the important indicators of the advancement of high-end equipment.

[0003] However, CFRP is also a typical difficult-to-machine material, and its machining faces three major challenges: First, its anisotropy and low interlayer strength make it prone to irreversible damage such as delamination, burrs and tearing during machining, which seriously affects the service life of the component; second, its high hardness causes severe abrasive wear on the cutting tool, resulting in short tool life and frequent tool replacement; and third, its low thermal conductivity makes cutting heat easy to accumulate in the machining area, leading to material deformation and workpiece damage.

[0004] Therefore, the machining of CFRP places high demands on cutting fluids: the cutting fluid used in CFRP machining must possess the dual functions of efficient cooling and strong lubrication. On the one hand, it must be able to quickly remove cutting heat, strictly controlling the temperature of the machining zone below the glass transition temperature of the resin to prevent thermal damage; on the other hand, the cutting fluid must form a high-strength lubricating film at the interface between the tool and the fiber, reducing cutting force and frictional heat, thereby inhibiting delamination and tearing, and slowing down tool wear. Furthermore, commercially available conventional cutting fluids may cause material swelling, leading to problems such as dimensional deviations in components or interface debonding.

[0005] To address the aforementioned challenges, it is necessary to develop a water-based cutting fluid specifically for CFRP. While some existing technologies have reported on water-based cutting fluids, such as those using fatty acid soaps, polyoxyethylene phosphates, sulfurized fatty acid esters, or polymeric esters as lubricating additives, these studies primarily focus on metal processing and do not address the specific requirements of CFRP processing, such as swelling resistance and chip dispersion. Similarly, research on environmentally friendly water-based fully synthetic cutting fluids uses isomeric fatty acid alcohol amine salts and n-ol laurate as lubricating additives and polyethers as surfactants, but their formulations are not optimized for the processing characteristics of CFRP. Therefore, developing a high-performance water-based cutting fluid specifically for CFRP has significant industrial value, and existing technologies require further improvement and development. Summary of the Invention

[0006] In view of the shortcomings of the prior art, the purpose of this invention is to provide a CFRP water-based cutting fluid and its preparation method, aiming to solve the technical problems of poor lubrication, insufficient cooling effect, easy material swelling, severe tool wear, and easy chip agglomeration in the CFRP processing of existing cutting fluids.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A CFRP water-based cutting fluid, comprising, by mass percentage: 13-16% ester lubricant, 12-14% polyether lubricant, 3-5% organic base, 2-3% rust inhibitor, 4-6% surfactant, 0.4-0.5% complexing agent, 4-5% biological stabilizer, 0.4-0.6% metal deactivator, 0.1-0.3% defoamer, with the balance being deionized water.

[0008] The CFRP water-based cutting fluid wherein the ester lubricant is a compound of trimethylolpropane oleate, tetrameric castor oil oleate and guerbert alcohol, with a compounding ratio of 5.5:6.5:1 to 6.7:8:1.3.

[0009] The CFRP water-based cutting fluid, wherein the polyether lubricant is an ethylene oxide-propylene oxide trans-block copolymer.

[0010] The CFRP water-based cutting fluid wherein the organic base is a compound of diethylene glycolamine and triethanolamine, with a compounding ratio of 1.5:2.5 to 2:4.

[0011] The CFRP water-based cutting fluid, wherein the rust inhibitor is one or more of the following: N-oleoylsarcosine octadecylamine salt, oleoylsarcosine, hydroxyethylidene diphosphonic acid, diethylenetriaminepentaacetic acid, tartaric acid, citric acid, succinic acid, sodium petroleum sulfonate, zinc naphthenate, alkenyl succinic acid, tribasic acid, etc.

[0012] The CFRP water-based cutting fluid wherein the surfactant is one or more of lauramidopropylamine oxide, tallow amine polyoxyethylene ether, oleylamine polyoxyethylene ether, dodecylamine polyoxyethylene ether, fatty alcohol polyoxyethylene ether, alkylphenol polyoxyethylene ether, oleyl alcohol polyoxyethylene ether, oleic acid polyoxyethylene ether, Span-80, Tween-80, etc.

[0013] The CFRP water-based cutting fluid wherein the complexing agent is one or more of the following: disodium ethylenediaminetetraacetate, tetrasodium ethylenediaminetetraacetate, sodium tripolyphosphate, sodium pyrophosphate, sodium hexametaphosphate, heptaphosphate, sodium gluconate, sodium alginate, hydroxyethylidene diphosphate, and maleic acid-acrylic acid copolymer.

[0014] The CFRP water-based cutting fluid wherein the bio-stabilizer is one or more of the following: triazine derivatives, monomorpholine derivatives, bismorpholine derivatives, isothiazolinone derivatives, etc.

[0015] The CFRP water-based cutting fluid is wherein the metal deactivator is one of thiadiazole derivatives, benzotriazole derivatives, benzotriazole, methylbenzotriazole, methylbenzotriazole sodium salt, etc.; and the defoamer is one or more of glycerol polyoxyethylene ether, polyvinyl alcohol, higher alcohols, organosilicon, polyether-modified silicone, etc.

[0016] A method for preparing a CFRP water-based cutting fluid as described in this invention, comprising the following steps: Organic alkali, ester lubricant and rust inhibitor are mixed and stirred at 50-55℃ until the solution is homogeneous to obtain the initial mixed solution; Deionized water is slowly added to the initial mixed solution, and the mixture is stirred until the solution is clear and transparent to obtain a transparent mixed solution; A polyether lubricant, a metal deactivator, a biological stabilizer, a complexing agent, a surfactant, and a defoamer are added sequentially to the transparent mixed solution, and the mixture is stirred until the solution is homogeneous to obtain a CFRP water-based cutting fluid.

[0017] Beneficial Effects: This invention utilizes the synergistic effect of ester-based and polyether-based lubricants to rapidly form a high-strength composite lubricating film at the interface between the cutting tool and CFRP. The ester-based lubricant is directionally adsorbed onto the metal surface through its polar groups, forming a dense adsorption film; the polyether-based lubricant, utilizing its inverse solubility, precipitates in the high-temperature friction zone to form an extreme pressure lubricating film. The two complement each other, significantly improving the load-bearing capacity and high-temperature stability of the lubricating film. The cutting fluid of this invention uses water as a base, possessing high specific heat capacity and thermal conductivity, enabling rapid removal of cutting heat and strictly controlling the temperature of the machining zone below the glass transition temperature of the epoxy resin, preventing thermal damage and deformation of the material. Simultaneously, the reverse solubility of polyether lubricants allows them to automatically accumulate on the friction surface in high-temperature zones, providing lubrication without affecting the cooling effect of the aqueous phase, achieving a perfect balance between cooling and lubrication. This invention addresses the problem of the epoxy resin matrix in CFRP easily swelling due to solvents by selecting ester lubricants and surfactants with larger molecular sizes and lower polarity, and strictly controlling the type and amount of organic bases, effectively avoiding swelling of the resin matrix and interfacial debonding. CFRP chips are fibrous, easily agglomerating and adhering to the tool and workpiece surfaces, affecting machining quality and tool life. This invention addresses this through the synergistic effect of polyether lubricants, surfactants, and complexing agents. This invention imparts excellent dispersibility to the cutting fluid. Polyether lubricants and surfactants reduce interfacial tension, allowing chips to quickly detach from the machining zone and suspend in the fluid. Complexing agents prevent chip agglomeration due to electrostatic interactions by chelating metal ions. The invention adjusts the pH of the cutting fluid to a weakly alkaline state (8.5-9.5) using an organic base (a mixture of diethylene glycolamine and triethanolamine), which inhibits bacterial growth and provides a good rust-preventing environment for machine tools and cutting tools. The rust inhibitor oleoyl sarcosine and the metal deactivator benzotriazole derivative work synergistically to form a dense protective film on the metal surface, significantly improving rust prevention. Prolonged immersion of CFRP chips and workpieces can easily lead to… To address the issue of cutting fluid spoilage and deterioration, this invention employs a bio-stabilizer composed of triazine derivatives and isothiazolinone derivatives. Triazine bactericides can rapidly kill bacteria, while isothiazolinones have a long-lasting inhibitory effect on fungi and yeasts. The synergistic effect is optimal when the ratio of the two is 3:1, achieving a balance between rapid sterilization and long-lasting bacteriostasis. This invention uses low-toxicity, biodegradable raw materials, free from harmful substances such as nitrites and phenols. The organic base compound avoids the irritating gases that may be produced by single ethanolamine, causing no irritation to the operator's skin and respiratory tract. The polyether-modified silicone defoamer is used in small quantities, defoams quickly, and does not affect the performance of the cutting fluid, meeting the requirements of green manufacturing. Attached Figure Description

[0018] Figure 1 This is a flowchart of a method for preparing a CFRP water-based cutting fluid according to the present invention. Detailed Implementation

[0019] This invention provides a CFRP water-based cutting fluid and its preparation method. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the following examples are provided to further illustrate the invention in detail. It should be understood that the specific examples described herein are only for explaining the invention and are not intended to limit the scope of protection of the invention.

[0020] This invention provides a CFRP water-based cutting fluid, which, by mass percentage, comprises the following components: 13-16% ester lubricant, 12-14% polyether lubricant, 3-5% organic base, 2-3% rust inhibitor, 4-6% surfactant, 0.4-0.5% complexing agent, 4-5% biological stabilizer, 0.4-0.6% metal deactivator, 0.1-0.3% defoamer, with the balance being deionized water.

[0021] The CFRP water-based cutting fluid provided by this invention is a complex system with multiple components working synergistically. Each component plays a different but interconnected role in the CFRP machining process, jointly achieving excellent machining performance. Among them, ester lubricant is the core lubricating component of this invention. By forming a molecularly oriented adsorption film in the friction zone, it prevents direct contact between the tool and the workpiece, thereby reducing friction and wear. Its mechanism of action is as follows: the polar ester groups (-COOR) in the ester molecules act on the surface of the metal tool through physical or chemical adsorption, forming a dense lubricating film; the non-polar long-chain alkyl groups are directed towards the friction interface, reducing the coefficient of friction. The selection of a mass percentage range of 13-16% is based on the following considerations: below 13%, the lubricating film coverage is insufficient, failing to form a complete lubricating isolation layer between the tool and CFRP, leading to increased cutting force and accelerated tool wear. Experiments show that when the ester lubricant content is below 11%, the four-ball friction coefficient exceeds 0.09, and the wear scar diameter is greater than 0.40 mm. A concentration above 16% will increase system costs, and excessive ester lubricants may lead to decreased emulsion stability or even oil separation and stratification. At the same time, excessive esters may pose a risk of swelling to the epoxy resin matrix in CFRP.

[0022] Polyether lubricants in this invention possess a unique reverse-solubility lubrication mechanism. Polyethers, represented by ethylene oxide-propylene oxide copolymers, are completely soluble in water at room temperature, presenting a transparent solution. However, at high temperatures at the friction interface (typically exceeding the cloud point), their hydrogen bonds are broken, solubility decreases, and they precipitate from the water, forming a very thin enriched lubricating film on the friction surface, providing extreme pressure lubrication. Once away from the high-temperature zone, the polyether automatically redissolves in the water. This temperature-responsive characteristic makes it particularly suitable for CFRP machining, which requires instantaneous high-pressure cooling and lubrication: providing lubrication at high temperatures in the cutting zone without affecting cooling in the non-cutting zone. The selection of a 12-14% mass percentage range is based on the following considerations: below 12%, the enriched lubricating film formed at high temperatures is insufficient to effectively bear the cutting load, especially when encountering hard carbon fibers in CFRP machining, where the lubricating film is prone to rupture; above 14%, excessive polyether content may increase the viscosity of the cutting fluid, affecting cooling performance; simultaneously, excessive polyether may precipitate excessively in the cutting zone, hindering heat transfer. Organic bases play multiple roles in this invention: First, they react with the carboxyl groups in ester lubricants and rust inhibitors to form water-soluble salts, allowing these oily substances to be uniformly dispersed in water; second, they adjust the pH of the cutting fluid to a slightly alkaline range (8.5-9.5), which is beneficial for inhibiting bacterial growth and providing a suitable rust-preventive environment for machine tools and cutting tools. The selection of a 3-5% mass percentage range is based on the following considerations: below 3%, the neutralization reaction is incomplete, some oily components cannot be fully emulsified, leading to decreased system stability; simultaneously, the pH may be below 8.5, resulting in insufficient rust prevention and antibacterial properties; above 5%, the pH may exceed 9.5, and excessive alkalinity may corrode non-ferrous metals such as aluminum alloys, and may also irritate the operator's skin. The function of rust inhibitor is to form a hydrophobic protective film on the metal surface, preventing moisture and oxygen from contacting the metal, thereby preventing rust. Choosing a range of 2-3% can form a complete protective film without affecting the emulsion stability due to excessive amount. In this invention, surfactants mainly function as emulsifiers, dispersers, and cleaners. They reduce the interfacial tension between oil and water, allowing oily components such as ester lubricants to be uniformly dispersed in water, forming a stable microemulsion. Simultaneously, surfactants adsorb onto the surface of CFRP chips, preventing chip aggregation and adhesion. The selection of a range of 4-6% is based on the HLB value requirements and critical micelle concentration of the emulsion system: below 4%, emulsification is incomplete, resulting in poor system stability; above 6%, excessive foaming may occur, increasing costs. During use, machine tool metal ions may precipitate out of the cutting fluid, or the water used to prepare the fluid may be too hard. These metal ions (such as calcium, magnesium, and iron) can affect the long-term stability of the cutting fluid, and may even cause emulsion demulsification or precipitation. Complexing agents can form stable water-soluble complexes with these metal ions, preventing their negative impact on the performance of the cutting fluid. Simultaneously, complexing agents can also adsorb onto the chip surface through chelation, changing its surface charge and preventing chip agglomeration caused by electrostatic effects. The selection of a range of 0.4-0.5% is based on typical metal ion concentrations: below 0.4%, the complexing ability is insufficient; above 0.5%, the improvement is not significant and may affect the stability of other components.

[0023] CFRP is an organic compound. When workpieces or chips are immersed in cutting fluid for a long time, it can easily induce the growth of bacteria and fungi, leading to the deterioration and spoilage of the cutting fluid, resulting in odor, discoloration, or even failure. Bio-stabilizers can inhibit the growth of microorganisms and extend the service life of the cutting fluid. The selection of a range of 4-5% is based on the concentration requirements for bactericidal and bacteriostatic effects: below 4%, the bacteriostatic effect is insufficient, and the cutting fluid is prone to spoilage; above 5%, it may irritate the operator's skin and increase the difficulty of environmental treatment.

[0024] Metal deactivators can form a complex adsorption film on metal surfaces, providing excellent protection, especially for copper and copper alloys. In CFRP machining, cutting tools are mostly made of cemented carbide (containing cobalt). Metal deactivators can prevent cobalt ion dissolution and extend tool life. The selection of a range of 0.4-0.6% is based on surface coverage requirements: below 0.4%, the protective film is incomplete; above 0.6%, multilayer adsorption may form, with limited improvement in effectiveness.

[0025] Cutting fluid is prone to foaming during high-speed spraying, which can affect cooling efficiency and machining stability. Defoamers reduce surface tension, causing foam to dissipate quickly. An optimized dosage of 0.1-0.3% effectively defoams without affecting other properties or causing oil stains due to excessive use.

[0026] Using deionized water can prevent calcium and magnesium ions in tap water from reacting with the cutting fluid components, thus ensuring system stability.

[0027] In some embodiments, the ester lubricant is a blend of trimethylolpropane oleate, tetrameric ricinoleate, and guerbert alcohol, with a blending ratio of 5.5:6.5:1 to 6.7:8:1.3. This embodiment limits the ester lubricant to a specific blend of trimethylolpropane oleate, tetrameric ricinoleate, and guerbert alcohol based on an in-depth analysis of CFRP processing conditions and a thorough understanding of the mechanisms of action of each component. Trimethylolpropane oleate is a polyol ester containing three ester groups in its molecular structure, which can form multi-point adsorption on the metal surface, enhancing the strength and stability of the lubricating film. Its regular molecular structure and tightly packed adsorption film make it a key component in forming the basic adsorption film, effectively withstanding cutting loads. Tetrameric ricinoleate is a polymeric ester, polymerized from four ricinoleic acid molecules, with a relatively long molecular chain (carbon chain length...). With up to 72 carbon atoms or more, it can form a thick elastic fluid lubricating film on the friction surface, exhibiting excellent extreme pressure anti-wear properties. Its long molecular chains can deform under high pressure without breaking, acting as a buffer pad. It is a key component for enhancing the load-bearing capacity of the lubricating film, and is particularly suitable for the impact loads encountered in CFRP processing. Guerbert alcohol is a branched alcohol with excellent wettability and penetrability. It can assist other lubricants in spreading quickly on the friction interface. Its branched structure can prevent excessively tight molecular arrangement, maintain the flexibility of the lubricating film, and enhance the penetration and coverage of fine and rough peaks. It is a key component for ensuring rapid and uniform coverage of the lubricating film.

[0028] The compounding ratios of 5.5:6.5:1 to 6.7:8:1.3 (trimethylolpropane oleate: tetrameric ricinoleate: Guerbert alcohol) in this embodiment are the result of extensive experimental optimization. For ease of understanding, both ratios are converted to a unified benchmark with Guerbert alcohol as 1: the first ratio is 5.5:6.5:1, and the second ratio is 6.7:8:1.3, which is converted to (6.7÷1.3):(8÷1.3):1≈ 5.15:6.15:1. Therefore, the actual protection range of this embodiment is from 5.15:6.15:1 to 5.5:6.5:1. The lower limit ratio is 5.15:6.15:1: this ratio is the minimum required to meet the processing performance requirements of CFRP. At this point, the relative contents of trimethylolpropane oleate and tetrameric ricinoleate are just enough to synergize with Guerbert alcohol to form a complete and effective lubricating film, achieving basic protective function. Below this ratio, the quality and performance of the lubricating film cannot be guaranteed; the upper limit is 5.5:6.5:1, which is the optimal balance between performance and economy. At this ratio, the synergistic effect of the three components is optimal, with the adsorption film strength provided by trimethylolpropane oleate, the extreme pressure anti-wear properties provided by tetrameric castor oil oleate, and the wetting and spreading properties provided by Guerbert alcohol all at their best. Above this ratio, not only will costs increase, but excessive amounts of components may also cause new problems.

[0029] If the ratio is lower than the lower limit, for example, 4.67:5.67:1, which is significantly lower than the lower limit of 5.15:6.15:1 in this invention, the relative content of trimethylolpropane oleate and tetrameric castor oil oleate is insufficient, resulting in: the basic adsorption membrane being insufficiently dense due to the relative insufficiency of trimethylolpropane oleate; the extreme pressure lubrication membrane being insufficiently strong due to the relative insufficiency of tetrameric castor oil oleate, unable to effectively bear the cutting load; and the overall quality of the lubrication membrane decreasing, with impaired extreme pressure and lubrication performance.

[0030] If the ratio exceeds the upper limit, for example, 6.25:7.5:1, which is significantly higher than the upper limit of 5.5:6.5:1 in this invention, the relative content of each component is too high. This leads to the following: excessive trimethylolpropane oleate may form an excessively thick adsorption layer, which may increase the internal friction between molecules and potentially increase frictional resistance; excessive tetrameric castor oil oleate with a large molecular weight may affect the emulsification stability of the system, leading to the risk of demulsification or decreased stability of the originally stable microemulsion. The final result is that the stability of the system is affected, manifested as poorer defoaming properties.

[0031] In some embodiments, the polyether lubricant is an ethylene oxide-propylene oxide trans-block copolymer. In this embodiment, the ethylene oxide-propylene oxide trans-block copolymer is a polyether with a special molecular structure, in which its hydrophilic (EO) and hydrophobic (PO) segments are arranged in blocks and exhibit trans-structure characteristics. Trans-block copolymers have a defined cloud point (typically 30-50°C). At room temperature, the EO segments form hydrogen bonds with water, and the polymer completely dissolves. When the temperature rises above the cloud point, the hydrogen bonds are broken, and the polymer precipitates from the water, forming a rich lubricating film on the friction surface. During CFRP cutting, the temperature in the machining zone can reach 200-300°C, which precisely triggers the precipitation of the polyether, achieving on-demand lubrication. Compared to random copolymers, trans-block copolymers exhibit more distinct hydrophilic and hydrophobic regions due to the aggregation of EO and PO segments, resulting in more pronounced anti-solubility and faster, more stable lubricating film formation. Furthermore, compared to normal-phase block copolymers, the hydrophilic segments of the trans-structure are located on the inner side, while the hydrophobic segments are on the outer side, which is more conducive to adsorption on metal surfaces. Additionally, trans-block copolymers can adsorb onto the surface of CFRP chips, preventing chip agglomeration through steric hindrance and improving chip removal performance.

[0032] In this embodiment, ethylene oxide-propylene oxide trans-block copolymer was chosen instead of other polyethers (such as PEG, random polyether, normal-phase block copolymer) because: PEG has no reverse solubility and cannot form an enriched lubricating film at high temperatures; random polyether has weak reverse solubility and the lubricating film forms slowly; the hydrophilic-hydrophobic balance of normal-phase block copolymer is not suitable for the emulsification requirements of this system; while the cloud point range (30-50℃) of the trans-block copolymer matches the temperature rise range of CFRP cutting.

[0033] In some embodiments, the organic base is a mixture of diethylene glycolamine and triethanolamine in a ratio of 1.5:2.5 to 2:4. In this embodiment, the organic base plays multiple roles in the CFRP water-based cutting fluid of the present invention: First, it reacts with the carboxyl groups in ester lubricants and rust inhibitors to form water-soluble salts, allowing these oily substances to be uniformly dispersed in water; second, it adjusts the pH of the cutting fluid to a weakly alkaline range, which is beneficial for inhibiting bacterial growth and providing a suitable rust-preventing environment for machine tools and cutting tools. Diethylene glycolamine molecules contain ether bonds and have good hydrophilicity. When combined with triethanolamine, it avoids the irritating gases that may be produced by using a single ethanolamine while meeting the pH range requirements, resulting in no irritation to the operator's skin and respiratory tract, thus enhancing safety.

[0034] In this embodiment, diethylene glycolamine and triethanolamine are compounded at a ratio of 1.5:2.5 to 2:4, resulting in the following synergistic effects: precise pH control: diethylene glycolamine provides strong alkalinity and high alkalinity reserves, while triethanolamine provides pH buffering capacity. The compounding of the two stabilizes the cutting fluid pH within the ideal range of 8.5-9.5; synergistic metal protection: diethylene glycolamine inhibits cobalt leaching and protects aluminum alloys, while triethanolamine protects ferrous metals. The compounding of the two achieves comprehensive protection for multiple metals; optimized safety: diethylene glycolamine alone is costly, and triethanolamine alone is not alkaline enough. The compounding can control costs while ensuring performance; at the same time, it avoids the risk of nitrosamines that may be generated when using diethanolamine.

[0035] In some embodiments, the rust inhibitor is one or more of the following: N-oleoylsarcosine octadecylamine salt, oleoylsarcosine, hydroxyethylidene diphosphonic acid, diethylenetriaminepentaacetic acid, tartaric acid, citric acid, succinic acid, sodium petroleum sulfonate, zinc naphthenate, alkenyl succinic acid, tricarboxylic acid, etc. Preferably, the rust inhibitor is oleoylsarcosine, an additive with both rust-preventing and lubricating functions. Its molecular structure contains long-chain alkyl groups and polar groups, which can form a dense adsorption film on the metal surface, effectively preventing moisture and oxygen from contacting the metal surface, thereby preventing corrosion. Simultaneously, its long-chain alkyl groups also have a certain lubricating effect, which can synergistically enhance the effect with ester lubricants.

[0036] In some embodiments, the surfactant is one or more of lauramidopropylamine oxide, tallow amine polyoxyethylene ether, oleylamine polyoxyethylene ether, dodecylamine polyoxyethylene ether, fatty alcohol polyoxyethylene ether, alkylphenol polyoxyethylene ether, oleyl alcohol polyoxyethylene ether, oleic acid polyoxyethylene ether, Span-80, Tween-80, etc., but is not limited thereto. Preferably, the surfactant is a blend of oleylamine polyoxyethylene ether and fatty alcohol polyoxyethylene ether in a blending ratio of 1.5:2.5 to 2.4:3.6. The surfactant mainly functions as an emulsifier, dispersant, and cleaner in this invention. Oleylamine polyoxyethylene ether contains unsaturated bonds and has a certain affinity for the carbon fiber surface, which helps the cutting fluid spread on the CFRP surface; fatty alcohol polyoxyethylene ether has good emulsifying and cleaning properties, ensuring further dispersion of functionalized components while preventing the agglomeration and adhesion of CFRP chips. The blend of the two can form mixed micelles with HLB values ​​that precisely match the oil-water phase composition of the system, achieving optimal emulsification. Meanwhile, the affinity of oleylamine polyoxyethylene ether for CFRP complements that of fatty alcohol polyoxyethylene ether for metals, enabling the cutting fluid to both wet the workpiece surface and clean the tool surface, preventing chip adhesion.

[0037] In some embodiments, the complexing agent is one or more of the following: disodium ethylenediaminetetraacetate, tetrasodium ethylenediaminetetraacetate, sodium tripolyphosphate, sodium pyrophosphate, sodium hexametaphosphate, heptaphosphate, sodium gluconate, sodium alginate, hydroxyethylidene diphosphate, and maleic acid-acrylic acid copolymer, but is not limited thereto. Preferably, the complexing agent is hydroxyethylidene diphosphate. During the use of cutting fluid, machine tool metal ions may precipitate, or the water used to prepare the fluid may be too hard. These metal ions (such as calcium, magnesium, iron, etc.) can affect the long-term stability of the cutting fluid, and may even lead to emulsion demulsification or precipitation. Hydroxyethylidene diphosphate is a highly efficient chelating agent that can form stable water-soluble complexes with various metal ions, preventing the negative impact of metal ions on the performance of the cutting fluid. Simultaneously, it also has a certain anti-rust effect and prevents chip aggregation and adhesion.

[0038] In some embodiments, the bio-stabilizer is one or more of triazine derivatives, monomorpholine derivatives, bismorpholine derivatives, isothiazolinone derivatives, etc., but is not limited thereto. Preferably, the bio-stabilizer is a mixture of triazine derivatives and isothiazolinone derivatives in a 3:1 ratio. Specifically, CFRP is an organic compound; when workpieces or chips are immersed in cutting fluid for extended periods, it easily induces bacterial and fungal growth, leading to fluid spoilage, odor, discoloration, and even failure. Triazine derivatives are rapid bactericides that can quickly kill existing bacteria; isothiazolinone derivatives are long-acting antibacterial agents with good inhibitory effects on fungi and yeasts. A 3:1 mixture of the two achieves a balance between rapid bactericidal action and long-acting inhibition, significantly extending the service life of the cutting fluid.

[0039] In some embodiments, the metal deactivator is one of thiadiazole derivatives, benzotriazole derivatives, benzotriazole, methylbenzotriazole, methylbenzotriazole sodium salt, etc., but is not limited thereto. Preferably, the metal deactivator is a benzotriazole derivative. The metal deactivator can work synergistically with the rust inhibitor to further alleviate the corrosion of machine tools and cutting tools. Among them, the benzotriazole derivative can form a complex adsorption film on the metal surface, especially showing excellent protective effect on copper and copper alloys. In this invention, it is combined with other rust-inhibiting components to achieve comprehensive protection for a variety of metals (cast iron, steel, copper, aluminum, etc.).

[0040] In some embodiments, the defoamer is one or more of glycerol polyoxyethylene ether, polyvinyl alcohol, higher alcohols, organosilicon, polyether-modified silicone, etc., but is not limited thereto. Preferably, the defoamer is polyether-modified silicone. Cutting fluid is prone to foaming during high-speed spraying, and foam can affect the cooling effect and processing stability. Polyether-modified silicone combines the good dispersibility of polyether with the strong defoaming ability of organosilicon. Only a small amount is needed to effectively suppress foam generation without affecting other properties of the cutting fluid.

[0041] In some embodiments, a method for preparing a CFRP water-based cutting fluid as described in this invention is also provided, such as... Figure 1 As shown, it includes the following steps: S10. Mix the organic base, ester lubricant and rust inhibitor, and stir at 50-55℃ until the solution is homogeneous to obtain the initial mixed solution; S20. Slowly add deionized water to the initial mixed solution and stir until the solution is clear and transparent to obtain a transparent mixed solution; S30. Add polyether lubricant, metal deactivator, biological stabilizer, complexing agent, surfactant and defoamer to the transparent mixed solution in sequence, and stir until the solution is uniform to obtain CFRP water-based cutting fluid.

[0042] Specifically, the preparation method of the present invention has a specific sequence of steps and process conditions, and its mechanism is as follows: In step S10, the organic base, ester lubricant, and rust inhibitor are mixed under heating conditions. The purpose is to allow the organic base to neutralize the carboxyl groups in the ester lubricant and rust inhibitor to generate a water-soluble salt. This reaction needs to be carried out at an appropriate temperature (50-55°C). If the temperature is too low, the reaction will be incomplete; if the temperature is too high, it may cause side reactions or component decomposition. Stirring until uniform ensures that the reaction proceeds fully. In step S20, deionized water is slowly added and stirred. The purpose is to dissolve the salt generated by the reaction in the water to form a clear and transparent solution. Slowly adding water can avoid local high concentrations that may lead to poor emulsification or precipitation. Stirring until clear and transparent indicates that the neutralization reaction product has been completely hydrated and dispersed. In step S30, the remaining components are added sequentially, especially the polyether lubricant, which is added at this time because it does not need to be pre-neutralized and can be uniformly dispersed directly upon addition. The sequential addition helps each component to gradually integrate into the system and avoids interactions that may lead to precipitation or stratification. The final product was a yellow, semi-transparent cutting fluid stock solution, indicating that the components had been uniformly dispersed to form a stable microemulsion system.

[0043] The CFRP water-based cutting fluid prepared by this invention is a cutting fluid concentrate. It should be diluted with water before use. It is recommended to dilute it according to the ratio of cutting fluid concentrate:water = 5:95-20:80. The specific dilution ratio can be adjusted according to the processing technology and material requirements.

[0044] The present invention will be further explained and illustrated below through specific embodiments: The raw materials used in the embodiments of this invention are all commercially available industrial products that can be purchased and used directly.

[0045] Example 1 A CFRP water-based cutting fluid, by mass percentage, comprises the following components: 13% ester lubricant, 12% polyether lubricant, 3% organic base, 2% rust inhibitor, 4% surfactant, 0.4% complexing agent, 4% biological stabilizer, 0.4% metal deactivator, 0.1% defoamer, and the balance being deionized water. The ester lubricant is a blend of trimethylolpropane oleate, tetrameric castor oil oleate, and guerbert alcohol in a ratio of 5.5:6.5:1; the polyether lubricant... It is an ethylene oxide-propylene oxide trans block copolymer; the organic base is a blend of diethylene glycolamine and triethanolamine in a ratio of 1.5:2.5; the rust inhibitor is oleylsarcosine; the surfactant is a blend of oleylamine polyoxyethylene ether and fatty alcohol polyoxyethylene ether in a ratio of 1.5:2.5; the complexing agent is hydroxyethylidene diphosphate; the biostabilizer is a blend of triazine derivative and isothiazolinone derivative in a ratio of 3:1; the metal deactivator is a benzotriazole derivative; and the defoamer is polyether-modified silicone.

[0046] The cutting fluid was prepared according to the above proportions using the following steps: 1. Mix organic bases (diethylene glycolamine and triethanolamine), ester lubricants (trimethylolpropane oleate, tetrameric castor oil oleate and Gelbert alcohol) and rust inhibitors (oleoyl sarcosine), and stir in a water bath at 50-55℃ for 30 minutes until the solution is homogeneous to obtain the initial mixed solution; 2. Slowly add deionized water to the initial mixed solution obtained in step 1 while stirring. After adding all the water, continue stirring for 20 minutes until the solution is clear and transparent, thus obtaining a transparent mixed solution. 3. To the transparent mixed solution obtained in step 2, add in sequence a polyether lubricant (ethylene oxide-propylene oxide trans block copolymer), a metal deactivator (benzotriazole derivative), a biological stabilizer (triazine derivative and isothiazolinone derivative), a complexing agent (hydroxyethylidene diphosphate), a surfactant (oleoamine polyoxyethylene ether and fatty alcohol polyoxyethylene ether), and a defoamer (polyether modified silicone). Stir for 5 minutes after each component is added, and finally continue stirring for 30 minutes until the solution is homogeneous to obtain a yellow semi-transparent cutting fluid stock solution.

[0047] Example 2 A CFRP water-based cutting fluid, by mass percentage, comprises the following components: 16% ester lubricant, 14% polyether lubricant, 5% organic base, 3% rust inhibitor, 6% surfactant, 0.5% complexing agent, 5% biological stabilizer, 0.6% metal deactivator, 0.3% defoamer, and the balance being deionized water. The ester lubricant is a blend of trimethylolpropane oleate, tetrameric castor oil oleate, and guerbert alcohol in a ratio of 6.7:8:1.3; the polyether lubricant... The lubricant is an ethylene oxide-propylene oxide trans-block copolymer; the organic base is a blend of diethylene glycolamine and triethanolamine in a ratio of 2:4; the rust inhibitor is oleylsarcosine; the surfactant is a blend of oleylamine polyoxyethylene ether and fatty alcohol polyoxyethylene ether in a ratio of 2.4:3.6; the complexing agent is hydroxyethylidene diphosphate; the biostabilizer is a blend of triazine derivative and isothiazolinone derivative in a ratio of 3:1; the metal deactivator is a benzotriazole derivative; and the defoamer is polyether-modified silicone. The preparation method is the same as in Example 1.

[0048] Example 3 A CFRP water-based cutting fluid, by mass percentage, comprises the following components: 14.5% ester lubricant, 13% polyether lubricant, 4% organic base, 2.5% rust inhibitor, 5% surfactant, 0.45% complexing agent, 4.5% biological stabilizer, 0.5% metal deactivator, 0.2% defoamer, and the balance being deionized water. The ester lubricant is a blend of trimethylolpropane oleate, tetrameric castor oil oleate, and guerbert alcohol in a ratio of 5.3:6.3:1. The ether-based lubricant is an ethylene oxide-propylene oxide trans-block copolymer; the organic base is a blend of diethylene glycolamine and triethanolamine in a ratio of 1:1.8; the rust inhibitor is oleylsarcosine; the surfactant is a blend of oleylamine polyoxyethylene ether and fatty alcohol polyoxyethylene ether in a ratio of 1:1.6; the complexing agent is hydroxyethylidene diphosphate; the biostabilizer is a blend of triazine derivative and isothiazolinone derivative in a ratio of 3:1; the metal deactivator is a benzotriazole derivative; and the defoamer is polyether-modified silicone. The preparation method is the same as in Example 1.

[0049] Comparative Example 1 (Ester lubricant content is lower than the scope of this invention) This comparative example provides a CFRP water-based cutting fluid with the same components as in Example 3, but the ester lubricant content is 10% (lower than the lower limit of 13% in this invention), and the contents of the other components are adjusted accordingly: 10% ester lubricant, 13% polyether lubricant, 4% organic base, 2.5% rust inhibitor, 5% surfactant, 0.45% complexing agent, 4.5% biological stabilizer, 0.5% metal deactivator, 0.2% defoamer, and deionized water to make up to 100%; the composition and preparation method of the other components are the same as in Example 3.

[0050] Comparative Example 2 (Ester lubricant content is higher than the scope of this invention) This comparative example provides a CFRP water-based cutting fluid with the same components as in Example 3, but the ester lubricant content is 18% (higher than the upper limit of 16% in this invention), and the contents of the other components are adjusted accordingly: ester lubricant 18%, polyether lubricant 13%, organic base 4%, rust inhibitor 2.5%, surfactant 5%, complexing agent 0.45%, biological stabilizer 4.5%, metal deactivator 0.5%, defoamer 0.2%, and deionized water to make up to 100%; the composition and preparation method of the other components are the same as in Example 3.

[0051] Comparative Example 3 (polyether lubricant content is lower than the scope of this invention) This comparative example provides a CFRP water-based cutting fluid with the same components as in Example 3, but the polyether lubricant content is 10% (lower than the lower limit of 12% in this invention), and the contents of the other components are adjusted accordingly: ester lubricant 14.5%, polyether lubricant 10%, organic base 4%, rust inhibitor 2.5%, surfactant 5%, complexing agent 0.45%, biological stabilizer 4.5%, metal deactivator 0.5%, defoamer 0.2%, and deionized water to make up to 100%; the composition and preparation method of the remaining components are the same as in Example 3. Comparative Example 4 (The proportion of ester lubricant in the formulation is higher than the upper limit of this invention) This comparative example provides a CFRP water-based cutting fluid with the same component content as Example 3, but the ester lubricant compounding ratio is 5.0:6.0:0.8, which, converted to a uniform standard with Guerbert alcohol as 1, is (5.0÷0.8):(6.0÷0.8):1=6.25:7.5:1. This ratio of 6.25:7.5:1 is significantly higher than the upper limit of 5.5:6.5:1 of this invention, and is above the upper limit ratio; the composition and preparation method of the remaining components are the same as in Example 3.

[0052] Comparative Example 5 (The proportion of ester lubricants in the formulation is lower than the lower limit of this invention) This comparative example provides a CFRP water-based cutting fluid with the same component content as Example 3, but the ester lubricant compounding ratio is 7.0:8.5:1.5. Converted to a uniform standard with Guerbert alcohol as 1: (7.0 ÷ 1.5):(8.5 ÷ 1.5):1≈4.67:5.67:1. This ratio of 4.67:5.67:1 is significantly lower than the lower limit of this invention (5.15:6.15:1), and is below the lower limit ratio; the composition and preparation method of the remaining components are the same as in Example 3.

[0053] Comparative Example 6 (the ratio of organic base to compound is lower than the lower limit of this invention) This comparative example provides a CFRP water-based cutting fluid with the same component content as in Example 3, but the organic base compounding ratio is 1.0:3.0 (lower than the lower limit of 2:4 of this invention). The organic base is still diethylene glycolamine and triethanolamine, but the ratio is adjusted to 1.0:3.0. The composition and preparation method of the remaining components are the same as in Example 3.

[0054] Comparative Example 7 (the ratio of organic base to compound is higher than the upper limit of this invention) This comparative example provides a CFRP water-based cutting fluid with the same component content as in Example 3, but the organic base compounding ratio is 1.5:2 (higher than the upper limit of 1.5:2.5 of this invention). The organic base is still diethylene glycolamine and triethanolamine, but the ratio is adjusted to 1.5:2. The composition and preparation method of the remaining components are the same as in Example 3.

[0055] Comparative Example 8 (using a single ester-based lubricant) This comparative example provides a CFRP water-based cutting fluid with the same component content as Example 3, but the ester lubricant is only trimethylolpropane oleate (single component), without tetrameric castor oil oleate and Guerbert alcohol. The total amount of ester lubricant is still 14.5%, but it is all trimethylolpropane oleate; the composition and preparation method of the remaining components are the same as in Example 3.

[0056] Comparative Example 9 (using a single organic base) This comparative example provides a CFRP water-based cutting fluid with the same component content as Example 3, but the organic base is only triethanolamine (single component), and diethylene glycolamine is not used. The total amount of organic base is still 4%, but it is all triethanolamine; the composition and preparation method of the remaining components are the same as in Example 3.

[0057] Comparative Example 10 (using ordinary PEG instead of trans-block polyether) This comparative example provides a CFRP water-based cutting fluid with the same component content as in Example 3, but the polyether lubricant is polyethylene glycol 600 (PEG-600), instead of ethylene oxide-propylene oxide trans block copolymer; the composition and preparation method of the remaining components are the same as in Example 3.

[0058] The cutting fluid stock solutions prepared in Examples 1-3 and Comparative Examples 1-10 were diluted with deionized water at a ratio of 5:95 to obtain diluted solutions, which were then used for various performance tests. The test methods are as follows: 1. Extreme pressure performance test The test was conducted according to GB / T 3142-2019 "Determination of Lubricant Load-Carrying Capacity - Four-Ball Method" to determine the maximum non-seizure load (P_B) and sintering load (P_D). Test instrument: Xiamen Tianji MS-10A four-ball friction testing machine. Test conditions: rotation speed 1450 r / min, room temperature approximately 20℃.

[0059] 2. Lubrication performance test Long-term wear tests were conducted using a four-ball friction testing machine, following the method specified in GB / T 3142. Test conditions: rotation speed 1200 rpm, load 40 kg (392 N), time 10 min. The average coefficient of friction and wear scar diameter were recorded. Testing instrument: Xiamen Tianji MS-10A four-ball friction testing machine.

[0060] 3. Tapping torque test The tapping torque tester was used for testing. Test conditions: rotation speed 800 r / min, tapping depth 10 mm, maximum torque 400 N·cm, cutting tool TTT-M4C-TIN-T, test block TC4 titanium alloy (standard test block, whose high hardness and poor thermal conductivity are similar to CFRP). Test instrument: TAP TTTSystem-G8 tapping torque tester.

[0061] 4. pH value test Refer to section 5.3 of GB / T6144-2010, and use a pH meter to determine the pH value of the diluted solution at 25°C.

[0062] 5. Defoaming test Refer to section 5.4 of GB / T6144-2010 to determine the foam volume (ml / 10min) of the diluted solution within 10 minutes.

[0063] 6. Corrosion test Referring to section 5.6 of GB / T6144-2010, the corrosion levels of cast iron, copper, and aluminum alloy specimens after immersion at 55±2℃ for 24 hours were tested and classified into four levels: A, B, C, and D. Level A is no corrosion, and level D is severe corrosion.

[0064] 7. Single-piece rust prevention test Referring to section 5.7.5 of GB / T6144-2010, the rust resistance level of cast iron single pieces after being placed at 35±2℃ and 95% humidity for 24 hours is tested and divided into four levels: A, B, C, and D. Level A is no rust, and level D is severe rust.

[0065] 8. Swelling performance test The procedure was conducted according to GB / T 11547-2008: CFRP material (T700 grade epoxy resin-based carbon fiber composite material) was cut into 60×60×1mm³ specimens, immersed in a cutting fluid dilution at 23±2℃ for 24 hours, removed, cleaned, and wiped dry. The side length and thickness were measured, and the expansion rate was calculated. Three specimens cut in different directions were used in parallel for each test. The swelling performance was expressed as the average expansion rate, which is the average of the calculated expansion rates of the three specimens.

[0066] The test results for each embodiment and comparative example are shown in Table 1.

[0067] Table 1 Performance Test Results

[0068] As can be seen from the data in Table 1 of the Examples and Comparative Examples 1-3, in Comparative Example 1 (ester lubricant 10% < 13%): extreme pressure performance decreased significantly (P_B = 63 kg, P_D = 160 kg), the coefficient of friction increased to 0.088, the wear scar diameter was 0.401 mm, the corrosion and rust prevention grade dropped to B, and a swelling rate of 0.15% appeared. This indicates that when the ester lubricant content is insufficient, the lubricating film coverage is insufficient, and it cannot effectively protect the tool and workpiece, while the rust prevention performance is also impaired; in Comparative Example 2 (ester lubricant 18% > 16%): defoaming properties deteriorated (2 ml of foam appeared), and slight swelling (0.08%) appeared. This indicates that excessive ester lubricant affects the stability of the system and may pose a swelling risk to the CFRP resin matrix. In Comparative Example 3 (polyether lubricant 10% < 12%): extreme pressure performance decreased (P_B = 65 kg, P_D = 160 kg), lubrication performance deteriorated, corrosion and rust prevention level decreased, and 0.12% swelling occurred. This indicates that when polyether is insufficient, the extreme pressure lubricating film at high temperatures is not fully formed and cannot effectively bear the cutting load. The above comparison verifies the critical significance of the component content range in this application; below the lower limit, performance decreases significantly, while above the upper limit, new problems arise.

[0069] As can be seen from the data in Table 1 of the examples and comparative examples 4-5, the ratio of comparative example 4 (ester compound ratio 5.0:6.0:0.8) after conversion to a unified standard is 6.25:7.5:1, which is higher than the upper limit of 5.5:6.5:1 in this invention. At this point, the relative content of each component is too high, leading to: excessive trimethylolpropane oleate potentially forming an excessively thick adsorption layer, which may increase frictional resistance; and excessive tetrameric castor oil oleate potentially affecting emulsification stability due to its large molecular weight. The final result is that the system stability is affected, defoaming properties deteriorate, and 2ml of foam appears. Although its lubrication performance (P_B=71kg, coefficient of friction 0.073, wear scar diameter 0.370mm) is acceptable, the decreased stability indicates the negative impact of exceeding the upper limit ratio on the system.

[0070] Comparative Example 5 (ester compound ratio 7.0:8.5:1.5): After conversion to a unified standard, the ratio is 4.67:5.67:1, which is lower than the lower limit of this invention, 5.15:6.15:1. At this point, the relative content of trimethylolpropane oleate and tetrameric castor oil oleate is insufficient, resulting in: an insufficiently dense basic adsorption film; insufficient extreme pressure lubrication film strength; and ultimately, a significant decrease in lubrication performance, with P_B dropping to 68 kg, a friction coefficient increasing to 0.081, a wear scar diameter increasing to 0.385 mm, and a corrosion and rust prevention grade dropping to B.

[0071] The above comparison verifies the rationality of the compounding ratio range in this application: only within the ratio range defined by this invention (converted to 5.15:6.15:1 to 5.5:6.5:1) can the three esters exert the best synergistic effect while ensuring the stability of the system.

[0072] As can be seen from the data in Table 1 of the Examples and Comparative Examples 6-7, in Comparative Example 6 (organic base compound ratio 1.0:3.0 < lower limit): the pH value dropped to 8.42 (below the ideal range), the corrosion and rust prevention level decreased significantly (Grade B and Grade C), and 0.10% swelling occurred. This indicates that when the proportion of diethylene glycolamine is insufficient, the base reserve is inadequate, the pH stability is poor, and the cobalt leaching inhibition is insufficient.

[0073] Comparative Example 7 (organic base mixture ratio 1.5:2 > upper limit): pH value increased to 9.68 (too high), corrosion grade decreased to B, and swelling rate increased to 0.18%. This indicates that when the diethylene glycolamine ratio is too high, the alkalinity may cause corrosion to aluminum alloys and may also irritate the skin. The above comparison verifies the critical significance of the organic base mixture ratio in this application.

[0074] As can be seen from the data in Table 1 of the Examples and Comparative Examples 8-9, Comparative Example 8 (single ester lubricant) exhibits significantly inferior performance compared to Example 3, with a P_B of only 65 kg, a P_D of only 160 kg, a friction coefficient of 0.089, a wear scar diameter of 0.408 mm, and a swelling rate as high as 0.22%. This indicates that a single ester cannot achieve the synergistic effect of a three-ester blend: trimethylolpropane oleate provides the basic adsorption film, tetrameric castor oleate enhances extreme pressure anti-wear properties, and Guerbert alcohol assists in rapid spreading and penetration; all three are indispensable. Comparative Example 9 (single organic base) shows a pH value reduced to 8.35, a corrosion and rust prevention grade reduced to C, and a swelling rate as high as 0.25%. This is consistent with literature studies on the performance of diethylene glycolamine: when triethanolamine is used alone, cobalt dissolution inhibition is insufficient, increasing the risk of aluminum corrosion; only a blend of diethylene glycolamine and triethanolamine can achieve a balance between pH stability and metal protection.

[0075] As can be seen from the data in Table 1 for Examples and Comparative Example 10, the P_B of Comparative Example 10 decreased to 60 kg (72 kg in Example 3), and the P_D decreased to 126 kg (200 kg in Example 3), showing a significant decrease. Regarding lubrication performance: the coefficient of friction of Comparative Example 10 was as high as 0.105 (0.071 in Example 3), and the wear scar diameter increased to 0.435 mm (0.362 mm in Example 3), indicating a severe deterioration in lubrication performance. Regarding rust prevention performance: the corrosion grade and rust prevention grade of Comparative Example 10 both decreased to Grade C (Grade A in Example 3), showing a significant decrease in rust prevention performance. Regarding swelling performance: the swelling rate of Comparative Example 10 was as high as 0.32% (0 in Example 3), indicating that PEG has a significant swelling effect on the CFRP resin matrix.

[0076] The experimental data of Comparative Example 10 strongly demonstrate that only by using trans-block polyethers with reverse solubility can an effective extreme pressure lubricating film be formed under the high-temperature conditions of CFRP processing, while maintaining good rust prevention and swelling resistance. Ordinary PEG cannot meet the technical requirements of CFRP processing.

[0077] It should be understood that the application of the present invention is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A CFRP water-based cutting fluid, characterized in that, By weight percentage, it contains the following components: 13-16% ester lubricant, 12-14% polyether lubricant, 3-5% organic base, 2-3% rust inhibitor, 4-6% surfactant, 0.4-0.5% complexing agent, 4-5% biological stabilizer, 0.4-0.6% metal deactivator, 0.1-0.3% defoamer, and the balance is deionized water.

2. The CFRP water-based cutting fluid according to claim 1, characterized in that, The ester lubricant is a compound of trimethylolpropane oleate, tetrameric castor oil oleate and guerbert alcohol, with a compounding ratio of 5.5:6.5:1 to 6.7:8:1.

3.

3. The CFRP water-based cutting fluid according to claim 1, characterized in that, The polyether lubricant is an ethylene oxide-propylene oxide trans block copolymer.

4. The CFRP water-based cutting fluid according to claim 1, characterized in that, The organic base is a mixture of diethylene glycolamine and triethanolamine, with a mixture ratio of 1.5:2.5 to 2:

4.

5. The CFRP water-based cutting fluid according to claim 1, characterized in that, The rust inhibitor is one or more of the following: N-oleoylsarcosine octadecylamine salt, oleoylsarcosine, hydroxyethylidene diphosphonic acid, diethylenetriaminepentaacetic acid, tartaric acid, citric acid, succinic acid, sodium petroleum sulfonate, zinc naphthenate, alkenyl succinic acid, tribasic acid, etc.

6. The CFRP water-based cutting fluid according to claim 1, characterized in that, The surfactant is one or more of the following: lauramidopropylamine oxide, tallow amine polyoxyethylene ether, oleylamine polyoxyethylene ether, dodecylamine polyoxyethylene ether, fatty alcohol polyoxyethylene ether, alkylphenol polyoxyethylene ether, oleyl alcohol polyoxyethylene ether, oleic acid polyoxyethylene ether, Span-80, Tween-80, etc.

7. The CFRP water-based cutting fluid according to claim 1, characterized in that, The complexing agent is one or more of the following: disodium ethylenediaminetetraacetate, tetrasodium ethylenediaminetetraacetate, sodium tripolyphosphate, sodium pyrophosphate, sodium hexametaphosphate, heptaphosphate, sodium gluconate, sodium alginate, hydroxyethylidene diphosphate, and maleic acid acrylic acid copolymer.

8. The CFRP water-based cutting fluid according to claim 1, characterized in that, The biostabilizer is one or more of the following: triazine derivatives, monomorpholine derivatives, bismorpholine derivatives, isothiazolinone derivatives, etc.

9. The CFRP water-based cutting fluid according to claim 1, characterized in that, The metal deactivator is one of the following: thiadiazole derivative, benzotriazole derivative, benzotriazole, methylbenzotriazole, sodium methylbenzotriazole, etc.; the defoamer is one or more of the following: glycerol polyoxyethylene ether, polyvinyl alcohol, higher alcohols, organosilicon, polyether-modified silicone, etc.

10. A method for preparing a CFRP water-based cutting fluid as described in any one of claims 1-9, characterized in that, Includes the following steps: Organic alkali, ester lubricant and rust inhibitor are mixed and stirred at 50-55℃ until the solution is homogeneous to obtain the initial mixed solution; Deionized water is slowly added to the initial mixed solution, and the mixture is stirred until the solution is clear and transparent to obtain a transparent mixed solution; A polyether lubricant, a metal deactivator, a biological stabilizer, a complexing agent, a surfactant, and a defoamer are added sequentially to the transparent mixed solution, and the mixture is stirred until the solution is homogeneous to obtain a CFRP water-based cutting fluid.

Images