U-shaped honing abrasive strip and preparation method thereof

Abstract

The invention provides a U-shaped honing abrasive strip. The U-shaped honing abrasive strip comprises a supporting layer and a working layer formed on the surface of the supporting layer. A U-shaped groove parallel to the long side is formed in the short side direction of the honing abrasive strip; the working layer is prepared from, by mass, 10%-15% of cobalt powder, 30%-40% of copper powder, 10%-15% of tin powder, 5%-10% of iron powder, 20%-30% of tantalum nitride and 5%-25% of diamond. The supporting layer is prepared from copper powder, tin powder, silicon carbide, aluminum oxide and tungsten powder. The invention further provides a preparation method of the U-shaped honing abrasive strip. Tantalum nitride is added into the working layer, so that the hardness and the strength of the honing abrasive strip are improved, and meanwhile, due to the arrangement of the U-shaped grooves, disordered patterns and multi-edge shapes can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of honing abrasive strips, and particularly relates to a U-shaped honing abrasive strip and a preparation method thereof. Background Art

[0003] In the prior art, conventional honing abrasive strips include silicon carbide abrasive strips or diamond abrasive strips. The honing grains are diamond or silicon carbide, and the bonding part usually uses copper powder, tin powder, etc. to ensure rapid sintering and uniform grain detachment during honing; during the preparation process, in order to reduce the sintering temperature, cobalt powder and silver powder are also added to the bonding raw materials; further, in order to reduce costs, iron powder is added to reduce the content of other components.

[0004] For the above-mentioned bonding materials, they only play a role of rapid bonding or are prone to grain detachment during honing. The hardness of the bonding part is relatively low, and the service life of the abrasive strip is short. At the same time, since the bonding materials used in the bonding part basically have no grinding and polishing effect, and due to the rapid grain detachment, chaotic patterns often appear, making the honed mesh patterns not meet the requirements of national VI or national VII standards. Therefore, providing a bonding material for honing abrasive strips is of great significance for the honed mesh patterns to meet the requirements. Summary of the Invention

[0005] The technical problem solved by the present invention is to provide a U-shaped honing abrasive strip. The U-shaped honing abrasive strip provided by the present application has high hardness and high strength, and can reduce the generation of chaotic patterns and multi-edges.

[0006] In view of this, the present application provides a U-shaped honing abrasive strip, including: a support layer and a working layer formed on the surface of the support layer; a U-shaped groove parallel to the long side is provided in the short side direction of the abrasive strip;

[0007] By mass percentage, the preparation raw materials of the working layer include: 10-15% of cobalt powder, 30-40% of copper powder, 10-15% of tin powder, 5-10% of iron powder, 20-30% of tantalum nitride, and 5-25% of diamond;

[0008] The preparation raw materials of the support layer include: copper powder, tin powder, silicon carbide, aluminum oxide and tungsten powder.

[0009] Preferably, by mass percentage, in the support layer, the content of the copper powder is 75-85%, the content of the tin powder is 3-5%, the content of the silicon carbide is 8-15%, the content of the aluminum oxide is 2-5%, and the content of the tungsten powder is 1-3%.

[0010] Preferably, in the working layer, the content of cobalt powder is 11-14%; and / or, the content of copper powder is 32-37%; and / or, the content of tin powder is 12-14%; and / or, the content of iron powder is 7-9%; and / or, the content of tantalum nitride is 22-28%; and / or, the content of diamond is 7-15%.

[0011] Preferably, in the support layer, the content of copper powder is 78-83%; and / or, the content of tin powder is 3.5-4.5%; and / or, the content of silicon carbide is 8.5-14%; and / or, the content of aluminum oxide is 3-4.5%; and / or, the content of tungsten powder is 1.5-2.5%.

[0012] Preferably, the ratio of the distance between the two parallel sides of the U-shaped groove to the width of the U-shaped groove is (1-2):6.

[0013] Preferably, in the working layer, the particle size of tantalum nitride is 20-30 μm, and / or, the particle sizes of the cobalt powder, the copper powder, the tin powder and the iron powder are each independently 100 μm or less; and / or, the particle size of the diamond is 54-64 μm; and / or, the distribution density of the diamond in the working layer is 50-120 pieces / mm 2 .

[0014] Preferably, in the support layer, the particle sizes of the copper powder, the tin powder and the tungsten powder are each independently selected from 100 μm or less.

[0015] The present application also provides a method for preparing the U-shaped honing strip, comprising the following steps:

[0016] S1) Mix the raw materials according to the proportion of the raw materials for preparing the working layer to obtain a working layer mixture;

[0017] Mix the raw materials according to the proportion of the raw materials for preparing the support layer to obtain a support layer mixture;

[0018] S2) After loading the working layer mixture and the support layer mixture into the mold, seal the mold with a cover plate; at the end of the working layer mixture near the cover plate, the cover plate is a cover plate with a protrusion corresponding to the U-shaped groove;

[0019] S3) Sinter the mixture after loading the mold to obtain a U-shaped honing strip.

[0020] Preferably, in step S1), during the preparation of the working layer mixture, the mixing time is 10-30 min; and / or, during the preparation of the support layer mixture, the mixing time is 10-30 min.

[0021] Preferably, in step S3), the sintering includes first sintering, second sintering, and third sintering performed in sequence;

[0022] The temperature of the first sintering is 400 - 500 °C, the heat preservation time is 1 - 3 min, and the pressure is 15 - 25 MPa;

[0023] The temperature of the second sintering is 600 - 700 °C, the heat preservation time is 5 - 7 min, and the pressure is 28 - 32 MPa;

[0024] The temperature of the third sintering is 720 - 780 °C, the heat preservation time is 8 - 10 min, and the pressure is 35 - 45 MPa.

[0025] The present application provides a U-shaped honing abrasive strip, including: a support layer and a working layer formed on the surface of the support layer. A U-shaped groove parallel to the long side is provided in the short side direction of the honing abrasive strip; by mass percentage, the preparation raw materials of the working layer include: 10 - 15% cobalt powder, 30 - 40% copper powder, 10 - 15% tin powder, 5 - 10% iron powder, 20 - 30% tantalum nitride, and 5 - 25% diamond; the preparation raw materials of the support layer include: copper powder, tin powder, silicon carbide, aluminum oxide, and tungsten powder; the U-shaped honing abrasive strip provided by the present application increases the durability of the working layer by adding tantalum nitride to the working layer, reduces the replacement frequency of the honing abrasive strip. At the same time, cobalt powder, copper powder, tin powder, and iron powder are used as binders to fix diamond and tantalum nitride into shape, maintaining uniform grain detachment of the honing abrasive strip during the wear process; the support layer plays a role in fixing the abrasive strip during the honing process, and due to the addition of silicon nitride and aluminum oxide, the strength of the support layer is enhanced; further, the setting of the U-shaped groove of the honing abrasive strip allows the coolant to fully penetrate into the U-shaped notch during honing, which can reduce the heat generated due to high-speed friction. At the same time, it can also take away the grit generated by the grain detachment of the honing abrasive strip, reducing the generation of crosshatch and multi-edges, thereby improving the quality and efficiency of the honing pattern. Description of the Drawings

[0026] Figure 1 It is a side physical photo of the U-shaped honing abrasive strip provided by the present invention;

[0027] Figure 2 It is a top-down physical photo of the U-shaped honing abrasive strip provided by the present invention;

[0028] Figure 3 It is a front-facing physical photo of the U-shaped honing abrasive strip provided by the present invention;

[0029] Figure 4 It is a structural schematic diagram of the mold cover plate during the preparation process of the U-shaped honing abrasive strip of the present invention;

[0030] Figure 5Schematic diagram of the crosshatch pattern of the cylinder liner after honing with the U-shaped honing strip prepared in Example 1 of the present invention;

[0031] Figure 6 Schematic diagram of the crosshatch pattern of the cylinder liner after honing with the U-shaped honing strip prepared in Example 2 of the present invention;

[0032] Figure 7 Schematic diagram of the crosshatch pattern of the cylinder liner after honing with the U-shaped honing strip prepared in Example 3 of the present invention;

[0033] Figure 8 Schematic diagram of the crosshatch pattern of the cylinder liner after honing with the U-shaped honing strip prepared in Comparative Example 1 of the present invention;

[0034] Figure 9 Schematic diagram of the crosshatch pattern of the cylinder liner after honing with the U-shaped honing strip prepared in Comparative Example 3 of the present invention. Detailed Description of the Invention

[0035] To further understand the present invention, the preferred embodiments of the present invention will be described below in conjunction with examples. However, it should be understood that these descriptions are only for further explaining the features and advantages of the present invention, rather than limiting the claims of the present invention.

[0036] The honing strips in the prior art have the following problems: the overall hardness is low and unstable, resulting in frequent replacement of honing strips, low efficiency, and uneven honing crosshatch patterns. The thermal conductivity of diamond and binder varies greatly, resulting in uneven heat distribution in the whole honing strip, thus reducing the durability. Further, a large amount of heat generated during the honing process cannot be dissipated in time, and the grains falling off and oil stains generated during the honing process cannot be taken away in time, which easily leads to disordered patterns, deteriorating the honing effect, and prone to generating multi-edge-shaped crosshatch patterns. To solve the above problems, the present application provides a U-shaped honing strip, which changes the composition of the raw materials in the honing strip by introducing tantalum nitride into the working layer, improving the hardness and strength of the honing strip, thereby enhancing the wear resistance and corrosion resistance of the honing strip, reducing the replacement frequency of the honing strip, improving the working efficiency and reducing the cost, while improving the working environment and reducing the dust and heat generated by the honing strip to protect the safety of the staff. Further, the honing strip is designed with a U-shaped groove to ensure that the grains falling off and dirt generated during the honing process are taken away in time, while playing a good role in cooling, and also obtaining a good and uniform crosshatch pattern effect, enabling the emissions of the honed engine to meet the national VI and national VII standards. Specifically, the embodiments of the present invention disclose a U-shaped honing strip, comprising: a support layer and a working layer formed on the surface of the support layer; a U-shaped groove parallel to the long side is provided in the short side direction of the honing strip;

[0037] In terms of mass percentage, the raw materials for preparing the working layer include: 10-15% cobalt powder, 30-40% copper powder, 10-15% tin powder, 5-10% iron powder, 20-30% tantalum nitride, and 5-25% diamond;

[0038] The raw materials for preparing the support layer include: copper powder, tin powder, silicon carbide, aluminum oxide, and tungsten powder.

[0039] In the U-shaped honing abrasive strip provided in this application, it includes a support layer and a working layer formed on the surface of the support layer. Among them, the working layer serves as the honing layer, and its raw materials include: cobalt powder, copper powder, tin powder, iron powder, tantalum nitride, and diamond; among the above raw materials, the cobalt powder, the copper powder, the tin powder, and the iron powder are all binders, and their main function is to fix and form the wear-resistant particles diamond and tantalum nitride, and keep uniform grain detachment during honing. Specifically, the cobalt powder, as a binder, has the function of increasing the hardness of the honing abrasive strip. The cobalt powder has good toughness and a low sintering temperature in the working layer, and at the same time can form an alloy with iron, which helps to improve the strength and overall performance of the honing abrasive strip; at the same time, it can significantly increase the wear resistance of the honing abrasive strip, and is more suitable for honing with high load and severe wear; since cobalt exists as trivalent oxide on the surface of the honing abrasive strip in the working layer, it helps to prevent corrosive media from penetrating into the matrix of the honing abrasive strip, thereby improving the corrosion resistance of the honing abrasive strip. The content of the cobalt powder is 10-15%, specifically, the content of the cobalt powder is 11-14%; for example, the content of the cobalt powder in this application is 10%, 11%, 12%, 13%, 14%, or 15%.

[0040] The copper powder exists as a binder in the honing abrasive strip. Copper can form tin bronze alloy with other alloys such as tin, which can improve the hardness and wear resistance of the honing abrasive strip; at the same time, copper has good ductility and plasticity, which helps the abrasive strip to maintain a stable shape during processing; further, the addition of copper can change the phase composition and structure of the working layer, and improve the density and stability of the working layer. Therefore, the addition of copper helps to improve the corrosion resistance of the abrasive strip. The content of the copper powder is 30-40%, specifically, the content of the copper powder is 32-37%; for example, the content of the copper powder in this application is 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%.

[0041] The tin powder mainly plays a bonding role. It can form tin bronze with the copper powder to improve the hardness of the working layer; at the same time, adding tin powder to the honing abrasive strip helps to reduce the rapid wear of the honing abrasive strip, thereby extending the service life of the honing abrasive strip. Adding tin powder to the honing abrasive strip is also beneficial to improving the corrosion resistance. The content of the tin powder is 10-15%, specifically, the content of the tin powder is 12-14%; for example, the content of the tin powder is 10%, 11%, 12%, 13%, 14%, 15%.

[0042] Iron powder mainly plays a role in sintering and bonding in the honing abrasive strip, and also serves as a skeleton, which can improve the hardness and strength of the abrasive strip; when combined with elements such as cobalt and copper, iron powder exhibits excellent wear resistance in the honing abrasive strip, and iron combines with cobalt to form a protective layer, improving the corrosion resistance of the honing abrasive strip. The content of iron powder is 5-10%, specifically, the content of iron powder is 7-9%; for example, the content of iron powder in this application is 5%, 6%, 7%, 8%, 9%, 10%.

[0043] In this application, the particle sizes of the cobalt powder, the copper powder, the tin powder, and the iron powder are independently 100 μm or less.

[0044] In summary, the above cobalt powder, copper powder, tin powder, and iron powder jointly affect the hardness, strength, wear resistance, and corrosion resistance of the honing abrasive strip. By adding the above raw materials and limiting their contents, the overall performance of the honing abrasive strip can be improved.

[0045] Diamond and tantalum nitride in the working layer act as wear-resistant particles and have a significant impact on the hardness, strength, wear resistance, and corrosion resistance of the honing abrasive strip. Diamond mainly functions as grinding and dressing in the honing abrasive strip; it has high hardness and strength, and can also improve the overall hardness and strength of the abrasive strip; diamond has excellent wear resistance, and the wear resistance of diamond particles enables the honing abrasive strip to remain sharp for a long time, extending its service life; at the same time, diamond has good chemical stability and is not easily corroded. Therefore, the abrasive strip containing diamond can also maintain good performance in a humid or corrosive environment. The content of diamond is 5-25%, specifically, the content of the diamond is 7-15%; for example, the content of diamond in this application is 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%.

[0046] Tantalum nitride is a super hard material with high hardness characteristics; as an additive to the honing abrasive strip, tantalum nitride can increase the hardness of the honing abrasive strip, making it suitable for a wider range of grinding and cutting applications; the addition of tantalum nitride can enhance the structural strength of the honing abrasive strip, enabling it to better withstand the pressure and impact during the grinding process. At the same time, tantalum nitride also improves the heat resistance of the honing abrasive strip, preventing performance degradation caused by high temperatures; tantalum nitride has excellent wear resistance, which can reduce the wear of the honing abrasive strip during the grinding process, thus making the honing abrasive strip containing tantalum nitride have a longer service life and higher grinding efficiency; at the same time, tantalum nitride shows good stability in various chemical environments and can resist the erosion of water vapor and other corrosive media. Therefore, the abrasive strip containing tantalum nitride can also maintain good performance in a corrosive environment. The content of tantalum nitride is 20-30%, specifically, the content of tantalum nitride is 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%.

[0047] In this application, the particle size of the tantalum nitride is 20-30 μm, the particle size of the diamond is 54-64 μm, and the distribution density of the diamond in the working layer is 50-120 pieces / mm 2 , specifically, the distribution density of the diamond in the working layer is 60-110 pieces / mm 2 , further, the distribution density of the diamond in the working layer is 85-100 pieces / mm 2 .

[0048] In summary, diamond and tantalum nitride, as important components or additives in the honing abrasive strip, can significantly improve the hardness, strength, wear resistance and corrosion resistance of the honing abrasive strip.

[0049] In this application, the support layer only plays a role in fixing the abrasive strip during the honing process of the honing abrasive strip. Since silicon carbide and alumina are added, the strength of the support layer can be enhanced. However, the support layer does not participate in honing, while the working layer does. When the working layer is ground, the life of the abrasive strip is also over, thus reducing the waste of the support layer in sequence and saving costs. The raw materials for preparing the support layer include: copper powder, tin powder, silicon carbide, aluminum oxide and tungsten powder; specifically, by mass percentage, in the support layer, the content of the copper powder is 75-85%, the content of the tin powder is 3-5%, the content of the silicon carbide is 8-15%, the content of the aluminum oxide is 2-5%, and the content of the tungsten powder is 1-3%. Specifically, the content of the copper powder is 78-83%; for example, in this application, the content of the copper powder is 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%. The content of the tin powder is specifically 3%, 3.5%, 4%, 4.5%, 5%. The content of the silicon carbide is 8.5-14%; for example, in this application, the content of the silicon carbide is 8%, 8.5%, 9%, 9.5%, 10%, 10.5%, 11%, 11.5%, 12%, 12.5%, 13%, 13.5%, 14%, 14.5%, 15%. The content of the aluminum oxide is 3-4.5%; for example, in this application, the content of the aluminum oxide is 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%. The content of the tungsten powder is 1.5-2.5%; for example, in this application, the content of the tungsten powder is 1%, 1.5%, 2%, 2.5%, 3%.

[0050] In this application, the honing abrasive strip is a honing abrasive strip with a U-shaped groove. Specifically, U-shaped grooves parallel to the long side are arranged in the short side direction of the honing abrasive strip. In the long side direction, the U-shaped grooves can completely penetrate the short side or partially penetrate the short side; the specific schematic diagram is as follows Figures 1 to 3 , where Figure 1 is the side schematic diagram of the honing abrasive strip, Figure 2 is the top view schematic diagram of the honing abrasive strip, Figure 3 is the front view schematic diagram of the honing abrasive strip. Specifically, the ratio of the distance between the two parallel sides (groove width) of the U-shaped groove to the width of the U-shaped groove is (1-2):6.

[0051] This application also provides a preparation method for the U-shaped honing abrasive strip, including the following steps:

[0052] S1) Mix the raw materials according to the proportion of the raw materials for the working layer to obtain the working layer mixture;

[0053] Mix the raw materials according to the proportion of the raw materials for the support layer to obtain the support layer mixture;

[0054] S2) After loading the working layer mixture and the support layer mixture into the mold, seal the mold with a cover plate; at the end of the working layer mixture near the cover plate, the cover plate is a cover plate with a protrusion corresponding to the U-shaped groove;

[0055] S3) Sinter the mixture in the mold to obtain a U-shaped honing abrasive strip.

[0056] In the preparation process of the U-shaped honing abrasive strip, the working layer mixture and the support layer mixture are first prepared. The mixing method is carried out in a manner well-known to those skilled in the art, and this application does not impose special restrictions on this. Specifically, the working layer mixture and the support layer mixture can be respectively mixed in a mixer. The mixing time is independently 10 - 30 min. Specifically, the mixing time is 20 min.

[0057] This application then loads the working layer mixture and the support layer mixture into the mold and seals the mold with a cover plate; in the above-mentioned mold loading process, the support layer mixture is placed at the bottom of the mold, the working layer is laid flat on the support layer mixture, and the cover plate is a cover plate with a protrusion corresponding to the U-shaped groove, specifically as Figure 4 shown, to form a U-shaped groove on the honing abrasive strip.

[0058] Finally, this application sinters the mixture in the mold to obtain a U-shaped honing abrasive strip. The sintering includes gradient sintering, specifically including the first sintering, the second sintering, and the third sintering carried out in sequence; more specifically, the temperature of the first sintering is 400 - 500 °C, the holding time is 1 - 3 min, and the pressure is 15 - 25 MPa; the temperature of the second sintering is 600 - 700 °C, the holding time is 5 - 7 min, and the pressure is 28 - 32 MPa; the temperature of the third sintering is 720 - 780 °C, the holding time is 8 - 10 min, and the pressure is 35 - 45 MPa.

[0059] In this application, the sintering is carried out using a vacuum hot press sintering furnace for sintering and forming; the specific process includes:

[0060] ① Sample placement: Place the mold filled with the mixture in the corresponding position in the furnace, tighten the screw to press the sample, and close the cover door;

[0061] ② Vacuum pumping: Turn on the vacuum pump switch, and close the exhaust valve when the vacuum degree reaches 200 Pa;

[0062] ③ Set the pressure, temperature, and holding time: Use the step sintering forming method. The temperature is set to 450 °C in the first stage, hold for 3 min, and the pressure is set to 20 MPa; in the second stage, set to 650 °C, hold for 5 min, and the pressure is set to 30 MPa; in the third stage, set to 750 °C, hold for 8 min, and the pressure is set to 35 MPa;

[0063] ④Pressurization: When the settings are completed, turn on the press switch. When the pressure rises to 5 Mpa, turn on the power supply of the temperature control system. At this time, the temperature starts to rise. When the set temperature is reached, hot pressing begins. Finally, after three times of heating and constant temperature, and applying pressure, until the final pressure reaches the maximum and the heat preservation time is reached, the hot pressing and sintering are completed;

[0064] ⑤Cooling and demolding: When the entire program is completed, turn on the water cooler to cool the sand strip mold. After it is completely cooled, take out the sample.

[0065] The U-shaped honing abrasive strip provided by this application, by adding tantalum nitride powder particles with high hardness and high strength, can improve the overall hardness and strength of the abrasive strip, ensure that the abrasive strip has a certain hardness and strength during the grinding process, and can fall off evenly and slowly. At the same time, due to the high hardness, the uniformity and consistency of the grinding grooves can be increased; at the same time, because the thermal conductivity of tantalum nitride is close to that of diamond, the durability of the abrasive strip is increased; further designed into a U-shaped groove can reduce the generation of chatter marks and multi-edges.

[0066] To further understand the present invention, the following is a description of the U-shaped honing abrasive strip and its preparation method provided by the present invention in combination with embodiments. The protection scope of the present invention is not limited by the following embodiments.

[0067] Example 1

[0068] An economical and environmentally friendly U-shaped honing abrasive strip is composed of a support layer and a working layer formed on the surface of the support layer;

[0069] The preparation raw materials of the working layer include: cobalt powder: 12%, copper powder: 35%, tin powder: 13%, iron powder: 7%, tantalum nitride: 25%, the particle size of tantalum nitride is 20 - 30 μm, and the particle size of other raw materials is below 100 μm; the balance is diamond, and the particle size is D54;

[0070] The preparation raw materials of the support layer include: copper powder: 80%, tin powder: 4%, silicon carbide: 10%, aluminum oxide: 4%, tungsten powder: 2%; the particle sizes of the above raw materials are all less than 100 μm;

[0071] The preparation method of the U-shaped honing abrasive strip specifically includes the following steps:

[0072] 1. Mixing: According to the above ratios of the working layer and support layer raw materials, respectively weigh the masses of different components. Put the working layer raw materials and support layer raw materials into a mixer respectively, and start the mixer to mix for 20 minutes respectively to ensure that the different component raw materials in each layer are fully mixed, and obtain the working layer mixture and the support layer mixture;

[0073] 2. Molding:

[0074] ① Weigh 8.5 g of the support layer mixture and evenly spread it in a mold, then level it with a scraper.

[0075] ② Weigh 14 g of the working layer mixture and evenly spread it on top of the support layer mixture, and level it with a scraper.

[0076] ③ Cover the mold with a cover plate with a horizontal plate in the middle having a height of 4 mm and a width of 2 mm.

[0077] 3. Sintering: Use a vacuum hot pressing sintering furnace for sintering and forming. The specific operations and parameters are as follows:

[0078] ④ Sample placement: Place the mold filled with the mixture in the corresponding position in the furnace, tighten the screw to press the sample tightly, and close the cover door.

[0079] ⑤ Vacuum pumping: At this time, turn on the vacuum pump switch. When the vacuum degree reaches 200 Pa, close the exhaust valve at this time.

[0080] ⑥ Set the pressure, temperature, and holding time: Use the step sintering and forming method. The temperature is set to 450 °C in the first stage, hold for 3 min, and the pressure is set to 20 MPa; in the second stage, set to 650 °C, hold for 5 min, and the pressure is set to 30 MPa; in the third stage, set to 750 °C, hold for 8 min, and the pressure is set to 35 MPa.

[0081] ⑦ Pressurization: When the setting is completed, turn on the press switch. When the pressure rises to 5 MPa, turn on the power supply of the temperature control system. At this time, start heating. When the set temperature is reached, start hot pressing. Finally, after three times of heating and constant temperature, and applying pressure until the final pressure reaches the maximum and the holding time is reached, the hot pressing sintering is completed.

[0082] ⑧ Cooling and demolding: When the entire program is completed, turn on the water cooler to cool the sand strip mold. After it is completely cooled, take out the sample. The sample is a sand strip with a length of 100 mm, a width of 6 mm, and a height of 6 mm. Among them, the working layer is 4 mm high, the support layer is 2 mm high, and the trench width of the U-shaped groove is 2 mm.

[0083] 4. Trimming: Trim and polish the sand strip on a grinding wheel.

[0084] 5. Detection: Use a Rockwell hardness tester to detect the hardness HRE: 118, and use a microscope to measure the distribution density of diamonds: 89 pieces / mm 2 .

[0085] When honing the cylinder liner with the honing sand strip prepared in this embodiment, the reticulation photo is as Figure 5 shown. It can be seen from Figure 5 that the honing reticulation is evenly distributed and the reticulation crossing angles are consistent.

[0086] Example 2

[0087] An economical and environmentally friendly U-shaped honing abrasive strip is composed of a support layer and a working layer formed on the surface of the support layer;

[0088] The preparation raw materials of the working layer include: cobalt powder: 11%, copper powder: 32%, tin powder: 15%, iron powder: 9%, tantalum nitride: 22%, the particle size of tantalum nitride is 20 - 30μm, and the particle size of other raw materials is below 100μm; the balance is diamond, and the particle size is D54;

[0089] The preparation raw materials of the support layer include: copper powder: 78%, tin powder: 5%, silicon carbide: 15%, aluminum oxide: 3%, tungsten powder: 3%; the particle sizes of the above raw materials are all less than 100μm;

[0090] The preparation method of the U-shaped honing abrasive strip specifically includes the following steps:

[0091] 1. Mixing: According to the above ratios of the raw materials of the working layer and the support layer, respectively weigh the masses of different components, put the raw materials of the working layer and the support layer into a mixer respectively, start the mixer and mix for 20 minutes respectively to ensure that the different component raw materials of each layer are fully mixed evenly, and obtain the working layer mixture and the support layer mixture;

[0092] 2. Molding:

[0093] ① Weigh 12.5g of the support layer mixture, spread it evenly in the mold, and then level it with a scraper;

[0094] ② Weigh 23g of the working layer mixture, spread it evenly on the top of the support layer mixture, and level it with a scraper;

[0095] ③ Cover the mold with a cover plate with a cross plate in the middle with a height of 4mm and a width of 2mm;

[0096] 3. Sintering: Use a vacuum hot pressing sintering furnace for sintering and forming, and the specific operations and parameters are as follows:

[0097] ④ Sample placement: Place the mold filled with the mixture in the corresponding position in the furnace, tighten the screw to press the sample, and close the cover door;

[0098] ⑤ Vacuum pumping: At this time, turn on the vacuum pump switch, and when the vacuum degree reaches 200Pa, close the exhaust valve at this time;

[0099] ⑥ Set the pressure, temperature and holding time: Use the step sintering forming method, the temperature in the first stage is set to 450°C, hold for 3 minutes, and the pressure is set to 20MPa; the second stage is set to 650°C, hold for 5 minutes, and the pressure is set to 30MPa; the third stage is set to 750°C, hold for 8 minutes, and the pressure is set to 35MPa;

[0100] ⑦Pressurization: When the settings are completed, turn on the press switch. When the pressure rises to 5 MPa, turn on the power supply of the temperature control system. At this time, the temperature starts to rise. When the set temperature is reached, hot pressing begins. Finally, after three times of heating and constant temperature, and applying pressure. Until the final pressure reaches the maximum and the heat preservation time is reached, the hot pressing and sintering are completed;

[0101] ⑧Cooling and demolding: When the entire program is completed, turn on the water cooler to cool the sand strip mold. After it is completely cooled, take out the sample. The sample is a sand strip with a length of 150 mm, a width of 6 mm, and a height of 7 mm. Among them, the working layer is 5 mm high, the support layer is 2 mm high, and the trench width of the U-shaped groove is 2 mm.

[0102] 4. Trimming: Trim and polish the sand strip on a grinding wheel;

[0103] 5. Detection: Use a Rockwell hardness tester to detect the hardness HRE: 122, and use a microscope to measure the distribution density of diamonds: 95 pieces / mm 2 。

[0104] When honing the cylinder liner with the honing sand strip prepared in this embodiment, the reticulation photo is as Figure 6 shown. It can be seen from Figure 6 that the honing reticulation is evenly distributed and the reticulation crossing angles are consistent.

[0105] Example 3

[0106] An economical and environmentally friendly U-shaped honing sand strip is composed of a support layer and a working layer formed on the surface of the support layer;

[0107] The raw materials for preparing the working layer include: cobalt powder: 14%, copper powder: 32%, tin powder: 12%, iron powder: 7%, tantalum nitride: 28%. The particle size of tantalum nitride is 20 - 30 μm, and the particle size of other raw materials is below 100 μm; the balance is diamond, and the particle size is D54;

[0108] The raw materials for preparing the support layer include: copper powder: 83%, tin powder: 3.5%, silicon carbide: 8.5%, aluminum oxide: 4.5%, tungsten powder: 1.5%; the particle sizes of the above raw materials are all less than 100 μm;

[0109] The preparation method of the U-shaped honing sand strip specifically includes the following steps:

[0110] 1. Mixing: According to the above ratios of the raw materials for the working layer and the support layer, weigh the masses of different components respectively. Put the raw materials for the working layer and the support layer into the mixer respectively, and start the mixer to mix for 20 minutes respectively to ensure that the different components of each layer are fully mixed, obtaining the working layer mixture and the support layer mixture;

[0111] 2. Molding:

[0112] ① Weigh 8.5 g of the support layer mixture and evenly spread it in a mold, then level it with a squeegee.

[0113] ② Weigh 14 g of the working layer mixture and evenly spread it on top of the support layer mixture, and level it with a squeegee;

[0114] ③ Cover the mold with a cover plate with a horizontal plate in the middle having a height of 4 mm and a width of 2 mm;

[0115] 3. Sintering: Use a vacuum hot pressing sintering furnace for sintering and forming. The specific operations and parameters are as follows:

[0116] ④ Sample placement: Place the mold filled with the mixture in the corresponding position in the furnace, tighten the screw to press the sample tightly, and close the cover door;

[0117] ⑤ Vacuum pumping: At this time, turn on the vacuum pump switch. When the vacuum degree reaches 200 Pa, close the exhaust valve at this time;

[0118] ⑥ Set the pressure, temperature, and holding time: Use the step sintering forming method. The temperature in the first stage is set to 450 °C, hold for 3 min, and the pressure is set to 20 MPa; in the second stage, set to 650 °C, hold for 5 min, and the pressure is set to 30 MPa; in the third stage, set to 750 °C, hold for 8 min, and the pressure is set to 35 MPa;

[0119] ⑦ Pressurization: When the setting is completed, turn on the press switch. When the pressure rises to 5 MPa, turn on the power supply of the temperature control system. At this time, start heating. When the set temperature is reached, start hot pressing. Finally, after three times of heating and constant temperature, and applying pressure. Until the final pressure reaches the maximum and the holding time is reached, the hot pressing sintering is completed;

[0120] ⑧ Cooling and demolding: When the entire procedure is completed, turn on the water cooler to cool the sand strip mold. After it is completely cooled, take out the sample. The sample is a sand strip with a length of 100 mm, a width of 6 mm, and a height of 6 mm, where the working layer is 4 mm high, the support layer is 2 mm high, and the trench width of the U-shaped groove is 2 mm.

[0121] 4. Trimming: Trim and polish the sand strip on a grinding wheel;

[0122] 5. Detection: Use a Rockwell hardness tester to detect the hardness HRE: 116, and use a microscope to measure the distribution density of diamond: 96 pieces / mm 2 。

[0123] When honing the cylinder liner with the honing sand strip prepared in this embodiment, the reticulation photo is as Figure 7 shown. It can be seen from Figure 7 that the honing reticulation is evenly distributed and the reticulation crossing angles are consistent.

[0124] Comparative Example 1

[0125] Component composition of a U-shaped honing abrasive strip:

[0126] The raw materials for preparing the working layer include: cobalt powder: 12%, copper powder: 35%, tin powder: 13%, iron powder: 7%. The particle size of the above raw materials is below 100 μm; the balance is diamond, and the particle size is D54.

[0127] The raw materials for preparing the support layer include: copper powder: 80%, tin powder: 4%, silicon carbide: 10%, aluminum oxide: 4%, tungsten powder: 2%; the particle size of the above raw materials is less than 100 microns.

[0128] The preparation method is the same as that of Example 1.

[0129] Detection: Use a Rockwell hardness tester to detect the hardness HRE: 98, and use a microscope to measure the distribution density of diamond: 91 pieces / mm 2 .

[0130] When honing the cylinder liner with the honing abrasive strip prepared in this example, the reticulation photo is as Figure 8 shown.

[0131] In this comparative example, tantalum nitride is missing, which affects the hardness and corrosion resistance of the honing abrasive strip; due to the reduction of hardness, the abrasion resistance of the abrasive strip is poor, the grain detachment is fast, and thus the life of the abrasive strip is shortened.

[0132] Comparative Example 2

[0133] Component composition of a U-shaped honing abrasive strip:

[0134] The raw materials for preparing the working layer include: cobalt powder: 12%, copper powder: 35%, tin powder: 13%, iron powder: 7%, tantalum nitride: 10%. The particle size of the above raw materials is below 100 μm; the balance is diamond, and the particle size is D54.

[0135] The raw materials for preparing the support layer include: copper powder: 80%, tin powder: 4%, silicon carbide: 10%, aluminum oxide: 4%, tungsten powder: 2%. The particle size of the above raw materials is less than 100 μm.

[0136] The preparation method is the same as that of Example 1.

[0137] Detection: Use a Rockwell hardness tester to detect the hardness HRE: 110, and use a microscope to measure the distribution density of diamond: 93 pieces / mm 2 .

[0138] Comparative Example 3

[0139] A preparation method of a honing abrasive strip:

[0140] The components and preparation process of the working layer and the support layer are the same as those in Example 1. In step 2, a flat cover plate is used for the mold cover plate. The obtained abrasive strip sample is an abrasive strip with a length of 100 mm, a width of 6 mm, and a height of 6 mm. Among them, the working layer is 4 mm high, the support layer is 2 mm high, and there is no U-shaped groove.

[0141] The detected hardness HRE is 120, and the distribution density of diamond is measured using a microscope: 90 pieces / mm 2 .

[0142] When honing the cylinder liner with the honing abrasive strip prepared in this example, the reticulation photo is as Figure 9 shown. It can be seen from Figure 9 that the reticulation after honing has generated disordered lines and the reticulation angles are inconsistent.

[0143] Comparative Example 4

[0144] A preparation method of a U-shaped honing abrasive strip:

[0145] The difference in the components and preparation process of the working layer from those in Example 1 is that diamond is replaced with silicon carbide, and other components remain unchanged.

[0146] The detection results are shown in Table 1.

[0147] Comparative Example 5

[0148] A preparation method of a U-shaped honing abrasive strip:

[0149] The difference in the components and preparation process of the working layer from those in Example 1 is that both diamond and tantalum nitride are replaced with silicon carbide, and other components remain unchanged.

[0150] The detection results are shown in Table 1.

[0151] Table 1 Performance data table of honing abrasive strips prepared in each example and comparative example

[0152]

[0153] The description of the above examples is only used to help understand the method and its core idea of the present invention. It should be noted that for those of ordinary skill in the art of this technology, without departing from the principle of the present invention, several improvements and modifications can still be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0154] The foregoing description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A U-shaped honing strip, comprising: A supporting layer and a working layer formed on a surface of the supporting layer; A U-shaped groove parallel to the long side is provided in the short side direction of the honing strip; In terms of mass percentage, the raw materials for preparing the working layer include: 10-15% cobalt powder, 30-40% copper powder, 10-15% tin powder, 5-10% iron powder, 20-30% tantalum nitride, and 5-25% diamond; The raw materials for preparing the support layer include: copper powder, tin powder, silicon carbide, aluminum oxide and tungsten powder.

2. The U-shaped honing strip according to claim 1, characterized in that: In terms of mass percentage, in the support layer, the content of the copper powder is 75-85%, the content of the tin powder is 3-5%, the content of the silicon carbide is 8-15%, the content of the aluminum oxide is 2-5%, and the content of the tungsten powder is 1-3%.

3. The U-shaped honing strip according to claim 1 or 2, characterized in that: In the working layer, the content of cobalt powder is 11-14%; and / or, the content of copper powder is 32-37%; and / or, the content of tin powder is 12-14%; and / or, the content of iron powder is 7-9%; and / or, the content of tantalum nitride is 22-28%; and / or, the content of diamond is 7-15%.

4. The U-shaped honing strip according to claim 1 or 2, characterized in that: In the support layer, the content of the copper powder is 78-83%; and / or, the content of the tin powder is 3.5-4.5%; and / or, the content of the silicon carbide is 8.5-14%; and / or, the content of the aluminum oxide is 3-4.5%; and / or, the content of the tungsten powder is 1.5-2.5%.

5. The U-shaped honing strip according to claim 1, characterized in that: The ratio of the distance between the two parallel sides of the U-shaped groove to the width of the U-shaped groove is (1-2):

6.

6. The U-shaped honing strip according to claim 1, characterized in that: In the working layer, the particle size of the tantalum nitride is 20 to 30 μm, and / or the particle sizes of the cobalt powder, the copper powder, the tin powder and the iron powder are independently less than 100 μm; and / or the particle size of the diamond is 54 to 64 μm; and / or the distribution density of the diamond in the working layer is 50 to 120 pieces / mm 2 .

7. The U-shaped honing strip according to claim 1, characterized in that: In the support layer, the particle sizes of the copper powder, the tin powder and the tungsten powder are independently selected to be less than 100 μm.

8. The method for preparing the U-shaped honing strip according to any one of claims 1 to 7, comprising the following steps: S1) mixing the raw materials according to the ratio of the raw materials for preparing the working layer to obtain a working layer mixture; Mixing the raw materials according to the ratio of raw materials for preparing the support layer to obtain a support layer mixture; S2) After the working layer mixture and the supporting layer mixture are loaded into a mold, the mold is sealed with a cover plate; the working layer mixture is close to the end of the cover plate, and the cover plate is a cover plate with a protrusion corresponding to the U-shaped groove; S3) sintering the molded mixed material to obtain a U-shaped honing strip.

9. The preparation method according to claim 8, characterized in that: In step S1), during the preparation of the working layer mixture, the mixing time is 10 to 30 minutes; and / or, during the preparation of the supporting layer mixture, the mixing time is 10 to 30 minutes.

10. The preparation method according to claim 8, characterized in that: In step S3), the sintering includes a first sintering, a second sintering and a third sintering performed in sequence; The first sintering temperature is 400-500°C, the holding time is 1-3 minutes, and the pressure is 15-25 MPa; The second sintering temperature is 600-700°C, the holding time is 5-7min, and the pressure is 28-32MPa; The temperature of the third sintering is 720-780° C., the holding time is 8-10 min, and the pressure is 35-45 MPa.

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