A special cleaning agent and cleaning method for a diamond compact

Abstract

The present application relates to the technical field of detergent, especially to a special cleaning agent for diamond compact and a cleaning method. The special cleaning agent for diamond compact is composed of the following raw materials in parts by weight: 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether 30-50 parts, trans-1-chloro-3,3,3-trifluoropropene 12-18 parts, trans-dichloroethylene 32-58 parts, alcohol solvent 1-5 parts, corrosion inhibitor 0.01-0.1 parts, stabilizer 0.01-1 parts, synergist 0.01-5 parts, functional additive 0.01-1 parts, metal protective agent 0.01-0.05 parts and chelating agent 0.05-0.2 parts. Through the progressive cleaning of 'pre-washing-peeling-precision bleaching-self-drying', the excellent effects of residue removal rate of more than 98.5% and cobalt loss amount of less than 1.5 ppm are realized, the process is simple, the energy consumption is low, and no additional baking is needed, which fully meets the high standard cleaning requirements of diamond compact.

Description

Technical Field

[0001] This invention relates to the field of detergent technology, and in particular to a special cleaning agent and cleaning method for diamond composite sheets. Background Technology

[0002] Diamond composite sheets (PDC) are formed by sintering polycrystalline diamond layers with a cemented carbide matrix under high temperature and pressure. Due to their excellent hardness and toughness, they have become a key material in oil and gas drilling, geological exploration, and precision machining. During their production, cobalt is typically added as a binder or catalyst to promote bonding between diamond particles. However, residual cobalt can catalyze the graphitization of diamond, and the significant difference in thermal expansion coefficients between cobalt and diamond can easily lead to thermal stress at high temperatures, resulting in performance degradation. Furthermore, after sintering, the surface of the composite sheet is contaminated with oil and processing impurities, requiring cleaning.

[0003] Currently, existing technologies for cleaning and cobalt removal from diamond composite sheets mainly include the following solutions: First, using acid immersion or electrolysis to remove cobalt. For example, CN107803507B discloses a method for deep cobalt removal using an acidic solution combined with positive and negative pressure pulses. However, this method is time-consuming, the strong acid severely corrodes the equipment, wastewater treatment is costly, and the acid easily corrodes the tungsten-cobalt alloy in the cemented carbide matrix, causing the workpiece surface to turn black or yellow. Second, using water-based cleaning agents combined with ultrasonic cleaning. For example, CN219025205U discloses a surface cleaning device, and CN121266894A discloses a vibration cleaning device. Water-based cleaning agents require hot water and rinsing, followed by baking and drying, resulting in a long process flow, high energy consumption, and the risk of cobalt corrosion. Furthermore, the wastewater containing heavy metal ions requires complex treatment. Third, using organic solvent cleaning agents combined with vapor phase cleaning processes. Existing patents CN102251249 disclose a cobalt-based alloy corrosion inhibitor and CN115646902A disclose a metal component cleaning process, but existing solvent cleaners either have a flash point that poses a risk of combustion, or have a high boiling point and high energy consumption, and have limited corrosion inhibition and protection effects on cobalt, making it difficult to achieve both degreasing and cobalt protection.

[0004] In summary, among existing diamond composite sheet cleaning technologies, acid-based cobalt removal methods are time-consuming and pose a high risk of corrosion; water-based cleaning agents present cobalt corrosion and wastewater treatment issues; and existing solvent-based cleaning agents still have shortcomings in terms of safety, energy consumption, and cobalt protection. Therefore, developing a dedicated cleaning agent and method for diamond composite sheets that can efficiently remove oil, avoid cobalt corrosion, is safe and environmentally friendly, and has a simple process has become an urgent technical problem to be solved in this field. Summary of the Invention

[0005] To meet the requirements of a special cleaning agent for diamond composite sheets that is highly efficient in removing oil, avoids cobalt corrosion, is safe and environmentally friendly, and has a simple process, this application provides a special cleaning agent and cleaning method for diamond composite sheets.

[0006] In the first aspect, this application provides a special cleaning agent for diamond composite sheets, which adopts the following technical solution: A special cleaning agent for diamond composite sheets, composed of the following raw materials in parts by weight: 30-50 parts of 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether; 12-18 parts of trans-1-chloro-3,3,3-trifluoropropene; 32-58 parts of trans-dichloroethylene; 1-5 parts of alcohol solvent; Corrosion inhibitor 0.01-0.1 parts; Stabilizer 0.01-1 part; Synergist 0.01-5 parts; Functional additives: 0.01-1 part; The functional additive is composed of one or more of perfluoromethyl hepten ether, perfluoropolyether sulfonate, perfluoropolyether quaternary ammonium salt, perfluoropolyether alcohol and perfluoropolyether carboxylic acid ester. The boiling range of the special cleaning agent for diamond composite sheets is 42-44℃.

[0007] The above technical solution comprises a specific ratio of azeotropic solvent system, alcohol solvent, corrosion inhibitor, stabilizer, synergist, and functional additives. Specifically, the azeotrope formed by 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether, trans-1-chloro-3,3,3-trifluoropropylene, and trans-dichloroethylene imparts a low boiling point and stable gas-phase cleaning performance to the cleaning agent, ensuring low-temperature boiling, rapid evaporation, and component-free fractionation. The alcohol solvent is used to adjust solubility and system compatibility. The corrosion inhibitor forms a chemical adsorption film on the tungsten-cobalt alloy surface, effectively inhibiting cobalt precipitation. The stabilizer prevents oxidative decomposition of the cleaning agent, extending its service life. The synergist enhances the penetration and removal of stubborn oil stains. The functional additives, with their low surface tension and amphiphilic properties, significantly enhance the wettability and penetration of the cleaning agent into the microporous structure of the diamond composite sheet surface, synergistically removing oil stains and preventing secondary deposition. Through a synergistic mechanism of "azeotropic-penetrating stripping-corrosion inhibition and protection", the components enable the cleaning agent to achieve efficient oil removal under low-temperature boiling conditions of 42-44℃, while avoiding acid and alkali corrosion and cobalt loss. The workpiece is bright and undiscolored after cleaning, and it does not require high-temperature baking, has no flash point, and is safe and environmentally friendly. Its comprehensive performance is significantly better than existing water-based and solvent-based cleaning agents.

[0008] Preferably, the alcohol solvent is any one of methanol, ethanol, and isopropanol.

[0009] Preferably, the corrosion inhibitor is any one of 2-mercaptobenzothiophene, benzotriazole, and triethanolamine oleate.

[0010] Preferably, the stabilizer is any one of 1,3-dioxolane, 2,6-di-tert-butyl-p-cresol, and triethanolamine.

[0011] Preferably, the synergist is any one of heptane, isoheptane, cyclohexane, isohexane, ethyl acetate, methyl formate, dimethyl carbonate, methyl acetal, acetone, and nitromethane.

[0012] More preferably, a cleaning agent for diamond composite sheets is composed of the following raw materials in parts by weight: 30-50 parts of 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether, 12-18 parts of trans-1-chloro-3,3,3-trifluoropropene, 32-58 parts of trans-dichloroethylene, 1-3 parts of isopropanol, 0.01-0.1 parts of 2-mercaptobenzothiophene, 0.1-0.5 parts of 1,3-dioxopentane, 1-3 parts of methyl acetal, and 0.1-0.5 parts of perfluoromethyl hepten ether.

[0013] Through the above technical solution, the components work synergistically within the optimized ratio range. Specifically, the azeotrope formed by 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether, trans-1-chloro-3,3,3-trifluoropropene, and trans-dichloroethylene in a specific ratio ensures a constant composition and stable boiling temperature of the cleaning agent during the gas-phase cleaning process, giving the cleaning process excellent repeatability and controllability. Isopropanol adjusts the solubility of the system, 2-mercaptobenzothiophene forms an adsorption film on the tungsten-cobalt alloy surface to inhibit cobalt corrosion, 1,3-dioxopentane prevents the oxidative decomposition of components, methyl acetal enhances the penetration and removal of oil stains, and perfluoromethyl hepten ether, with its extremely low surface tension, strengthens microporous wetting and prevents secondary adhesion. The synergistic effect of these components achieves a residue removal rate of over 99%, cobalt loss of less than 1.5 ppm, and a bright, discolored workpiece surface, all without the need for baking or drying, making it safe and environmentally friendly.

[0014] Preferably, the diamond composite sheet cleaning agent further includes 0.01-0.05 parts of a metal protectant; the metal protectant is one or more of N-(3-trimethoxysilylpropyl)imidazolium, N-(3-triethoxysilylpropyl)imidazolium, and N-(3-trimethoxysilylpropyl)benzotriazole.

[0015] Preferably, the diamond composite sheet cleaning agent further includes 0.05-0.2 parts of a chelating agent; the chelating agent is methylglycine diacetic acid or its alkali metal salt.

[0016] By adding metal protectants and chelating agents to the cleaning agent using the above technical solution, the cobalt protection effect is significantly improved. Specifically, nitrogen-containing heterocyclic silane metal protectants such as N-(3-trimethoxysilylpropyl)imidazolium can hydrolyze in situ on the tungsten-cobalt alloy surface and self-assemble to form a dense hydrophobic silane protective film, effectively preventing direct contact between the cleaning agent and the alloy substrate, thus inhibiting cobalt precipitation and oxidation at the source. Methylglycine diacetic acid (MGDA), as a biodegradable and highly effective chelating agent, can rapidly complex the cobalt ions that have already dissolved in small amounts, preventing secondary deposition on the workpiece surface. The synergistic effect of the "active film-forming protection" of the metal protectant and the "passive complexing and trapping" of the chelating agent further reduces cobalt loss to 0.3-0.4 ppm, leaving the workpiece surface bright and without any discoloration, and increasing the PDC wear ratio to 44.2 × 10⁻⁶. 3 In summary, this approach achieves optimal protection for the diamond composite sheet while ensuring efficient oil removal.

[0017] Secondly, this application provides a cleaning method for diamond composite sheets, using the diamond composite sheet cleaning agent described in the first aspect, comprising the following steps: S1. First vapor phase cleaning: Place the diamond composite sheet workpiece in a vapor phase cleaning tank, heat the special cleaning agent for diamond composite sheets to boiling, generate cleaning agent vapor, the vapor condenses and flows back on the surface of the workpiece, and washes the workpiece. The vapor phase cleaning temperature is 42-44℃, and the cleaning time is 3-5min. S2. Ultrasonic cleaning: The workpiece cleaned in step S1 is transferred to an ultrasonic cleaning tank. The liquid in the cleaning tank is a special cleaning agent for diamond composite sheets. Under normal temperature conditions, intermittent ultrasonic cleaning is used. S3. Second vapor phase cleaning: The workpiece cleaned in step S2 is transferred to the vapor phase cleaning tank again. The diamond composite sheet cleaning agent is heated to boiling and used to rinse and clean the workpiece. The vapor phase cleaning temperature is 42-44℃ and the cleaning time is 3-5 minutes. S4. Speed-controlled lifting and drying: After the second vapor phase cleaning, the workpiece is vertically lifted out of the vapor phase cleaning tank at a speed of 0.5-2 mm / s. No baking is required to complete the drying process.

[0018] Preferably, in step S2, the intermittent ultrasound is performed by pausing for 10-60 seconds after the ultrasound has been running for 3-5 minutes, and this cycle is repeated 2-3 times, with the ultrasound frequency being 35-45kHz.

[0019] Through the above technical solution, the synergistic effect of each step achieves a highly efficient, non-destructive, and simple cleaning effect. Specifically, the first vapor-phase cleaning uses clean vapor generated by an azeotropic cleaning agent to pre-rinse the workpiece, effectively softening and removing most of the surface oil. Intermittent ultrasonic cleaning uses a special cleaning agent for diamond composite sheets as the medium. Through alternating cycles of operation and pauses, it utilizes the ultrasonic cavitation effect to deeply peel away stubborn contaminants in micropores and crevices, while the pause phases avoid localized overheating and cavitation corrosion caused by continuous ultrasonication, protecting the workpiece surface. The second vapor-phase cleaning uses pure solvent vapor for a final precision rinsing of the workpiece, removing trace amounts of water stains and residual contaminants that may have been introduced by the ultrasonic steps. Controlled-speed lifting drying utilizes the surface tension of the liquid film to allow it to flow down naturally and evaporate, completing drying without baking. This four-step process, through a progressive cleaning logic of "pre-washing - peeling - fine rinsing - air drying," achieves an excellent residue removal rate of over 98.5% and a cobalt loss of less than 1.5 ppm. The process is simple, energy-efficient, and requires no additional baking, fully meeting the high-standard cleaning requirements of diamond composite sheets.

[0020] In summary, this application has the following beneficial effects: 1. This application utilizes an azeotrope formed by the compounding of 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether, trans-1-chloro-3,3,3-trifluoropropylene, and trans-dichloroethylene, along with other components, to impart a low boiling point and stable gas-phase cleaning performance to the cleaning agent. Combined with the penetration and stripping effect of low surface tension functional additives such as perfluoromethyl hepten ether, it achieves highly efficient removal of stubborn oil stains on the surface of diamond composite sheets under low-temperature boiling conditions, with a residue removal rate of over 98.5%.

[0021] 2. This application forms an adsorption protective film on the surface of tungsten-cobalt alloy by adding corrosion inhibitors such as 2-mercaptobenzothiophene, and further introduces nitrogen-containing heterocyclic silane metal protectants and methylglycine diacetic acid chelating agents to form a synergistic protection mechanism of "active film formation protection + passive complexation and capture", which effectively inhibits the precipitation and oxidation of cobalt, reduces the cobalt loss to 0.3-0.4 ppm, avoids blackening and yellowing of the workpiece surface, and ensures the wear resistance of PDC.

[0022] 3. The diamond composite sheet cleaning method of this application adopts a four-step process of "vapor phase cleaning - intermittent ultrasonic cleaning - secondary vapor phase cleaning - controlled speed lifting drying". It utilizes the low boiling point characteristics of the azeotropic cleaning agent and the mild cavitation effect of intermittent ultrasonic cleaning to achieve integrated cleaning and drying. It does not require oven baking, has a short process flow, low energy consumption, and the cleaning agent has no flash point. With the help of condensation recovery, it can achieve zero emissions, which is safe and environmentally friendly. Attached Figure Description

[0023] Figure 1The image shows the appearance of a diamond composite sheet workpiece after being cleaned using the cleaning method of Example 1.

[0024] Figure 2 The image shows the appearance of the diamond composite sheet after being cleaned using the cleaning method of Comparative Example 2. Detailed Implementation

[0025] The technical solutions of this application are further illustrated by specific embodiments below. These specific embodiments do not represent a limitation on the scope of protection of this application. Any non-essential modifications and adjustments made by others based on the concept of this application still fall within the scope of protection of this application.

[0026] Unless otherwise specified, the experimental methods shown in the following examples are conventional methods. All reagents and materials shown are commercially available products.

[0027] Among them, 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether, CAS No. 406-78-0; trans-1-chloro-3,3,3-trifluoropropene, CAS No. 102687-65-0; trans-dichloroethylene, CAS No. 156-60-5; isopropanol, CAS No. 67-63-0; methanol, CAS No. 67-56-1; ethanol, CAS No. 64-17-5; 2-mercaptobenzothiophene, CAS No. 149 -30-4, benzotriazole, CAS No. 95-14-7; 1,3-dioxopentane, CAS No. 646-06-0; 2,6-di-tert-butyl-p-cresol, CAS No. 128-37-0; triethanolamine, CAS No. 102-71-6; methyl acetal, CAS No. 109-87-5; ethyl acetate, CAS No. 141-78-6; dimethyl carbonate, CAS No. 616-38-6; acetone, CAS No. 67-64-1.

[0028] The present application will be further described in detail below with reference to embodiments and comparative examples. Example

[0029] Example 1 A method for cleaning diamond composite sheets is provided, comprising the following steps: S1. First vapor phase cleaning: The diamond composite sheet workpiece is placed in a vapor phase cleaning tank, and the special cleaning agent for diamond composite sheets is heated to boiling to generate cleaning agent vapor. The vapor condenses and flows back on the surface of the workpiece to rinse and clean the workpiece. The vapor phase cleaning temperature is 44℃ and the cleaning time is 4min. S2. Ultrasonic cleaning: Transfer the workpiece cleaned in step S1 to an ultrasonic cleaning tank. The liquid in the cleaning tank is a special cleaning agent for diamond composite sheets. Under normal temperature conditions, intermittent ultrasonic cleaning is used. The ultrasonic waves work for 4 minutes and pause for 30 seconds. This cycle is repeated 3 times. The ultrasonic frequency is 40kHz. S3. Second vapor phase cleaning: The workpiece cleaned in step S2 is transferred to the vapor phase cleaning tank again. The diamond composite sheet cleaning agent is heated to boiling and used to rinse and clean the workpiece. The vapor phase cleaning temperature is 44℃ and the cleaning time is 4min. S4. Speed-controlled lifting and drying: After the second vapor phase cleaning, the workpiece is vertically lifted out of the vapor phase cleaning tank at a speed of 1 mm / s, and drying is completed without baking.

[0030] The composition and dosage of the special cleaning agent for diamond composite sheets are shown in Table 1.

[0031]

[0032] Example 2 The difference from Example 1 is that the composition and dosage of the diamond composite sheet cleaning agent are shown in Table 1.

[0033] The cleaning method for a diamond composite sheet includes the following steps: Step S1: Vapor phase cleaning at 42°C for 3 minutes; Step S2: Intermittent ultrasonic cleaning, with ultrasonic waves operating for 3 minutes and then pausing for 10 seconds, repeated 3 times, with an ultrasonic frequency of 35 kHz; Step S3: Vapor phase cleaning at 42°C for 5 minutes; Step S4: The workpiece is vertically lifted out of the vapor phase cleaning tank at a speed of 0.5 mm / s, without baking, to complete the drying process.

[0034] Example 3 The difference from Example 1 is that the composition and dosage of the diamond composite sheet cleaning agent are shown in Table 1.

[0035] The cleaning method for a diamond composite sheet includes the following steps: Step S1: Vapor phase cleaning at 43°C for 5 minutes; Step S2: Intermittent ultrasonic cleaning, with ultrasonic waves operating for 5 minutes and then pausing for 60 seconds, repeated twice; Ultrasonic frequency: 45 kHz; Step S3: Vapor phase cleaning at 43°C for 5 minutes; Step S4: The workpiece is vertically lifted out of the vapor phase cleaning tank at a speed of 2 mm / s, without baking, to complete the drying process.

[0036] Examples 4-6 The difference from Example 1 is that the composition and dosage of the diamond composite sheet cleaning agent are shown in Table 1.

[0037] Examples 7-9 The difference from Example 1 is that the diamond composite sheet cleaning agent also includes a metal protectant and a chelating agent; the composition and dosage of the composite additive plating solution are shown in Table 2.

[0038]

[0039] Comparative Example Comparative Example 1 The difference from Example 1 is that no functional additive (perfluoromethyl hepten ether) is added to the diamond composite sheet cleaning agent, while the other components and dosages are the same as in Example 1.

[0040] Comparative Example 2 The difference from Example 1 is that a conventional water-based cleaning agent (composed of a composite nonionic surfactant and a composite corrosion inhibitor, referring to the method of Example 1 in CN201510343961.7) is used instead of the diamond composite sheet cleaning agent of the present invention.

[0041] Comparative Example 3 The difference from Example 1 is that a single-frequency ultrasonic wave (40kHz continuous operation, non-intermittent) is used in step S2, instead of the intermittent alternating mode of the present invention. The other steps and cleaning agent components are the same as in Example 1.

[0042] Comparative Example 4 The difference from Example 7 is that no metal protectant is added to the diamond composite sheet cleaning agent; only the chelating agent (0.1g of methylglycine diacetic acid) is retained, and the other components are the same as in Example 7.

[0043] Comparative Example 5 The difference from Example 7 is that no chelating agent is added to the diamond composite sheet cleaning agent, only the metal protectant (N-(3-trimethoxysilylpropyl)imidazolium 0.03g) is retained, and the other components are the same as in Example 7. Performance testing

[0044] 1. Surface residue removal rate: Weigh the surfaces before and after cleaning using a balance with an accuracy of 0.01 mg, and calculate the residue removal rate.

[0045] 2. Cobalt loss: XRF was used to detect the cobalt content in the cleaning solution and the change in cobalt content on the workpiece surface after cleaning.

[0046] 3. Surface appearance: Visually inspect the surface of the workpiece after cleaning to see if there is any blackening, yellowing or water stains.

[0047] 4. Wear ratio: The wear ratio of PDC is determined according to the method of JB / T 3235-2013 to reflect the effect of cleaning on the performance of composite sheet.

[0048] The diamond composite sheets cleaned using the methods of Examples 1-9 and Comparative Examples 1-5 were subjected to the above performance tests, and the test results are shown in Table 3.

[0049]

[0050] As shown in Table 3, the performance test results of Examples 1-9 all exhibited excellent cleaning effects, with residue removal rates exceeding 98%, cobalt loss controlled below 1.5 ppm, and the workpiece surface remaining bright and undiscolored after cleaning, while the wear ratio was maintained at 41.5 × 10⁻⁶. 3 The above demonstrates that the technical solution of the present invention has stable and reliable cleaning performance.

[0051] Examples 1-3 all demonstrated excellent cleaning performance. Among them, the diamond composite sheet cleaned according to the method in Example 1 showed the following cleaning effect: Figure 1 As shown, after cleaning, the workpiece surface exhibits a uniform, bright, silvery-gray metallic luster, with a consistent overall color and no blackening, yellowing, or discoloration. No residual oil, particles, or water stains are visible on the workpiece surface. The microscopic surface is smooth and flat, with no observed corrosion pits or signs of intergranular corrosion. Example 1 showed a removal rate of 99.5% and a wear ratio of 43.1 × 10⁻⁶. 3 Slightly better than Examples 2 and 3, while Example 2 showed a relatively high cobalt loss, indicating that the amount of component used has a certain impact on the cobalt protection effect. Examples 4 and 5 performed similarly to Example 1; Example 6 had a removal rate of 98.5% and an attenuation ratio of 41.5 × 10⁻⁶. 3 Slightly lower than Example 1.

[0052] Examples 7-9 (addition of metal protectant and chelating agent): Based on Example 1, the addition of a nitrogen-containing heterocyclic silane metal protectant and MGDA chelating agent significantly reduced cobalt loss to 0.3-0.4 ppm and improved the wear ratio. Example 7 showed superior overall performance. This indicates a synergistic effect between the metal protectant and the chelating agent: the metal protectant forms a self-assembled protective film on the tungsten-cobalt alloy surface, while the chelating agent complexes dissolved cobalt ions to prevent secondary deposition; the combined effect significantly inhibits cobalt loss.

[0053] Comparative Example 1 (without functional additives): The removal rate was only 85.3%, the cobalt loss was as high as 8.5 ppm, and the surface was slightly yellowed. This indicates that perfluoromethyl hepten ether - a functional additive - not only plays a hydrophobic and oleophobic role in the cleaning agent, but also promotes the penetration of the cleaning agent into the microporous structure by reducing surface tension, thus significantly improving the degreasing efficiency.

[0054] Comparative Example 2 (water-based cleaning agent): The removal rate of 92.1% is acceptable, but the cobalt loss is as high as 25.6 ppm, the surface is obviously blackened, and the wear ratio is only 30.5 × 10. 3 The cleaned workpiece is as follows: Figure 2As shown, the workpiece surface exhibits obvious blackening, with localized areas appearing dark gray to blackish-brown. The overall surface loses its metallic luster, with slightly lighter edges and a darker center, exhibiting typical oxidation discoloration characteristics. The blackened area is unevenly distributed, with some areas showing tiny black spots or streaks, presumably cobalt oxide residue formed after accelerated precipitation and oxidation of cobalt in hot water and alkaline environments. Compared to the bright, discolored surfaces of Examples 1-9 after cleaning, the workpiece surface in Comparative Example 2 shows significant deterioration. This blackening not only severely affects the product's appearance quality but, more importantly, indicates a substantial loss of cobalt binder from the tungsten-cobalt alloy matrix. This directly weakens the strength and toughness of the cemented carbide matrix, thus affecting the overall service life and reliability of the diamond composite sheet. Therefore, water-based cleaning agents are insufficient to meet the high-standard cleaning requirements of diamond composite sheets.

[0055] Comparative Example 3 (single-frequency ultrasound): The removal rate of 94.5% was lower than that of Example 1, while the cobalt loss of 5.2 ppm was higher than that of Example 1. This indicates that the intermittent ultrasonic cleaning mode allows the cavitation effect to act more fully on the workpiece surface through periodic pauses, while avoiding local overheating caused by continuous ultrasound, thus reducing potential damage to cobalt.

[0056] Comparative Example 4 (without metal protectant): Cobalt loss was 1.8 ppm, significantly higher than in Example 7. Although the removal rate of 99.2% was comparable to Example 7, the cobalt protection effect was significantly worse. This indicates that nitrogen-containing heterocyclic silane metal protectants are key components in reducing cobalt loss.

[0057] Comparative Example 5 (without chelating agent): Cobalt loss was 1.5 ppm, also higher than in Example 7. This indicates that the chelating agent MGDA plays an important role in complexing dissolved cobalt ions and preventing their secondary deposition on the workpiece surface. Comparative Examples 5 and 6 together demonstrate that metal protectants and chelating agents must be used synergistically to achieve optimal cobalt protection.

[0058] The above test results show that the diamond composite sheet cleaning agent and its matching cleaning method prepared in this application have significant advantages such as high cleaning efficiency, excellent cobalt protection, simple process, and safety and environmental friendliness. The test results of Examples 1-9 show that using the cleaning agent of this invention combined with the three-step process of "vapor phase cleaning - intermittent ultrasonic cleaning - secondary vapor phase cleaning," the surface residue removal rate reaches over 98.5%, with Example 7 reaching as high as 99.6%, while Comparative Example 1's removal rate is only 85.3%, confirming that the synergistic effect of functional additives and specific corrosion inhibitors is key to improving degreasing efficiency. Regarding cobalt protection, the cobalt loss in Examples 1-9 is controlled below 1.5 ppm, and in Examples 7-9 with the addition of metal protectants and chelating agents, it is further reduced to 0.3-0.4 ppm, while the cobalt loss in Comparative Example 2 is as high as 25.6 ppm. This indicates that the present invention effectively inhibits cobalt precipitation through a non-aqueous system, vapor phase cleaning, and synergistic protection mechanism, preventing the workpiece surface from turning black or yellow. Furthermore, the cleaning agent has a boiling range of 42-44℃, requires no oven drying, dries instantly upon application, has no flash point and poses no risk of combustion, and can achieve zero emissions when combined with condensation recovery. After cleaning, the PDC wear ratio remains consistently at 41.5×10⁻⁶. 3 The above demonstrates that the present invention can thoroughly remove oil without damaging the hardness and wear resistance of PDC.

[0059] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they are within the scope of the present invention.

Claims

1. A cleaning agent specifically for diamond composite sheets, characterized in that, It consists of the following raw materials in parts by weight: 30-50 parts of 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether; 12-18 parts of trans-1-chloro-3,3,3-trifluoropropene; 32-58 parts of trans-dichloroethylene; 1-5 parts of alcohol solvent; Corrosion inhibitor 0.01-0.1 parts; Stabilizer 0.01-1 part; Synergist 0.01-5 parts; Functional additives: 0.01-1 part; The functional additive is composed of one or more of perfluoromethyl hepten ether, perfluoropolyether sulfonate, perfluoropolyether quaternary ammonium salt, perfluoropolyether alcohol and perfluoropolyether carboxylic acid ester. The boiling range of the special cleaning agent for diamond composite sheets is 42-44℃.

2. The cleaning agent for diamond composite sheets according to claim 1, characterized in that, Preferably, the alcohol solvent is any one of methanol, ethanol, and isopropanol.

3. The cleaning agent for diamond composite sheets according to claim 1, characterized in that, The corrosion inhibitor is any one of 2-mercaptobenzothiophene, benzotriazole, and triethanolamine oleate.

4. The cleaning agent for diamond composite sheets according to claim 1, characterized in that, The stabilizer is any one of 1,3-dioxolane, 2,6-di-tert-butyl-p-cresol, and triethanolamine.

5. The cleaning agent for diamond composite sheets according to claim 1, characterized in that, The synergist is any one of heptane, isoheptane, cyclohexane, isohexane, ethyl acetate, methyl formate, dimethyl carbonate, methyl acetal, acetone, and nitromethane.

6. The cleaning agent for diamond composite sheets according to claim 1, characterized in that, It is composed of the following raw materials in parts by weight: 30-50 parts of 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether, 12-18 parts of trans-1-chloro-3,3,3-trifluoropropene, 32-58 parts of trans-dichloroethylene, 1-3 parts of isopropanol, 0.01-0.1 parts of 2-mercaptobenzothiophene, 0.1-0.5 parts of 1,3-dioxopentane, 1-3 parts of methyl acetal, and 0.1-0.5 parts of perfluoromethyl hepten ether.

7. The cleaning agent for diamond composite sheets according to claim 1, characterized in that, It also includes 0.01-0.05 parts of a metal protectant; the metal protectant is one or more of N-(3-trimethoxysilylpropyl)imidazolium, N-(3-triethoxysilylpropyl)imidazolium, and N-(3-trimethoxysilylpropyl)benzotriazole.

8. The cleaning agent for diamond composite sheets according to claim 1, characterized in that, It also includes 0.05-0.2 parts of a chelating agent; the chelating agent is methylglycine diacetic acid or its alkali metal salt.

9. A method for cleaning diamond composite sheets, characterized in that, The cleaning agent for diamond composite sheets as described in any one of claims 1-8 includes the following steps: S1. First vapor phase cleaning: Place the diamond composite sheet workpiece in a vapor phase cleaning tank, heat the special cleaning agent for diamond composite sheets to boiling, generate cleaning agent vapor, the vapor condenses and flows back on the surface of the workpiece, and washes the workpiece. The vapor phase cleaning temperature is 42-44℃, and the cleaning time is 3-5min. S2. Ultrasonic cleaning: The workpiece cleaned in step S1 is transferred to an ultrasonic cleaning tank. The liquid in the cleaning tank is a special cleaning agent for diamond composite sheets. Under normal temperature conditions, intermittent ultrasonic cleaning is used. S3. Second vapor phase cleaning: The workpiece cleaned in step S2 is transferred to the vapor phase cleaning tank again. The diamond composite sheet cleaning agent is heated to boiling and used to rinse and clean the workpiece. The vapor phase cleaning temperature is 42-44℃ and the cleaning time is 3-5 minutes. S4. Speed-controlled lifting and drying: After the second vapor phase cleaning, the workpiece is vertically lifted out of the vapor phase cleaning tank at a speed of 0.5-2 mm / s. No baking is required to complete the drying process.

10. A cleaning method for a diamond composite sheet according to claim 9, characterized in that, In step S2, the intermittent ultrasound is performed by pausing for 10-60 seconds after the ultrasound has been working for 3-5 minutes, and this cycle is repeated 2-3 times. The ultrasound frequency is 35-45kHz.

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