Abrasion-resistant explosion-proof cutting piece and preparation method thereof

Abstract

The application discloses a wear-resistant and explosion-proof cutting piece and a preparation method thereof, and belongs to the field of abrasive materials. The cutting piece comprises liquid phenolic resin 10-15 parts, powder phenolic resin 5-15 parts, abrasive 60-90 parts, modified silicon carbide whisker 8-16 parts and ice crystal 4-8 parts. The modified silicon carbide whisker is high-temperature carbonized after being compounded with phosphatized cyclodextrin, graphene oxide and Zn-MOF, and forms a multi-scale gradient interface structure of'silicon carbide whisker-carbon network-nano zinc oxide'. The application significantly improves the interface bonding strength, impact resistance and wear resistance through the synergistic effect of resin compounding, whisker reinforcement and catalytic carbonization. Tests show that the bending strength of the cutting piece reaches 100.1 MPa, the impact strength reaches 11.4 kJ / m 2 , the mass loss rate is as low as 4.9%, the hardness is 78 HRB, the comprehensive performance is excellent, and the problems of poor wear resistance and easy explosion of the existing cutting piece are solved.

Description

Technical Field

[0001] This invention belongs to the field of abrasive material technology and relates to a wear-resistant and explosion-proof cutting disc and its preparation method. Background Technology

[0002] Cutting discs (also known as abrasive wheels or cutting wheels) are essential tools widely used in the cutting and processing of materials such as metal, stone, ceramics, and glass. With the increasing demands for processing precision and efficiency in modern manufacturing, the operating speed of cutting discs is constantly increasing. In some applications, the linear speed of the cutting disc has exceeded 80 m / s, which places higher demands on the wear resistance, impact resistance, and safety of the cutting disc.

[0003] Currently, resin-bonded cutting discs typically use phenolic resin as a binder and are manufactured through a hot-pressing process. They offer advantages such as good self-sharpening properties, low processing temperature, and low cost. However, under high-speed, heavy-load cutting conditions, they present the following technical problems: First, insufficient wear resistance. During high-speed cutting, abrasive particles in traditional resin-bonded cutting discs easily detach from the resin matrix under the cutting force, leading to decreased cutting efficiency and shortened disc life. This premature abrasive detachment is particularly pronounced when cutting high-hardness materials. Second, poor impact resistance, posing a risk of disc breakage. The cutting disc experiences significant wear during high-speed rotating cutting. During the cutting process, if subjected to impact loads (such as encountering hard points during cutting or lateral stress due to improper operation), the entire piece is prone to breakage or even bursting, and flying fragments may cause serious injury to the operator. Secondly, the bonding strength between the resin binder and the abrasive is insufficient. In the existing technology, the bonding between the abrasive and the phenolic resin binder mainly relies on physical interlocking and weak chemical adsorption, resulting in limited interfacial bonding strength, which is difficult to meet the requirements of high-speed heavy-duty cutting. Finally, the heat dissipation performance is poor. If the large amount of heat generated during the cutting process cannot be dissipated in time, it will lead to thermal decomposition of the resin binder and accelerate the failure of the cutting disc.

[0004] To address the aforementioned problems, some improvements have been proposed in the existing technology. For example, toughening agents (such as nitrile rubber) are added to the resin binder to improve toughness, or hard fillers (such as silicon carbide or alumina powder) are added to improve wear resistance. However, these improvements often come at the expense of one aspect: toughening modification often leads to a decrease in hardness and wear resistance, while adding hard fillers may reduce toughness, making it difficult to balance wear resistance and impact resistance.

[0005] Therefore, developing a cutting disc that combines excellent wear resistance, high impact resistance (explosion-proof), high interfacial bonding strength, good heat dissipation performance, and simple manufacturing process has significant industrial application value.

[0006] Therefore, this invention is proposed to solve the above-mentioned technical problems. Summary of the Invention

[0007] The purpose of this invention is to solve the technical problems of abrasive grain shedding, breakage risk and short life of cutting discs caused by insufficient wear resistance, poor impact resistance and low bonding strength between resin and abrasive interface.

[0008] To achieve the above objectives, the first aspect of the present invention provides a wear-resistant and explosion-proof cutting disc, which comprises the following components by weight: 10-15 parts of liquid phenolic resin, 5-15 parts of powdered phenolic resin, 60-90 parts of abrasive, 8-16 parts of modified silicon carbide whiskers, and 4-8 parts of cryolite.

[0009] Through the above technical solution, liquid and powdered phenolic resins are used in combination. The liquid resin provides good flowability and wettability, facilitating uniform dispersion of the mixture, while the solid resin provides skeletal support and a cross-linking network. During hot pressing, they synergistically form a dense cured body, improving the mechanical strength and heat resistance of the cutting disc. The introduction of modified silicon carbide whisker phase forms a three-dimensional reinforcing skeleton inside the cutting disc, significantly improving its impact resistance and wear resistance. Cryolite, as an active filler, melts and absorbs heat at the high cutting temperature, playing a lubricating and cooling role, reducing frictional heat, preventing resin thermal decomposition, and promoting abrasive self-sharpening.

[0010] As a preferred embodiment of this application, the method for preparing the modified silicon carbide whisker phase includes the following steps:

[0011] S1. After mixing and reacting β-cyclodextrin with concentrated phosphoric acid at 90°C, phosphorylated cyclodextrin is obtained.

[0012] S2. The phosphorylated cyclodextrin described in step S1 is ultrasonically dispersed in deionized water, graphene oxide nanosheets are added, the mixture is stirred and reacted, then filtered and dried to obtain cyclodextrin / graphene composite powder.

[0013] S3. Disperse the cyclodextrin / graphene composite powder from step S2 in a solvent, add zinc nitrate hexahydrate and 5-aminoisophthalic acid, stir the reaction, filter and dry to obtain the cyclodextrin / graphene / Zn-MOF composite.

[0014] S4. The silicon carbide whiskers, cyclodextrin / graphene / Zn-MOF composite and deionized water are ultrasonically mixed, centrifuged and dried, and then placed in a tube furnace for high-temperature carbonization under an inert atmosphere to obtain functionalized silicon carbide whiskers.

[0015] Through the above technical solution, β-cyclodextrin possesses a unique "internal hydrophobic, external hydrophilic" cavity structure. First, phosphorylated cyclodextrin is prepared by reacting β-cyclodextrin with phosphoric acid, introducing phosphate groups with strong coordination ability into the cyclodextrin molecule. The surface of graphene oxide contains abundant hydroxyl and carboxyl functional groups, which can be attached to the graphene surface by the phosphorylated cyclodextrin. Furthermore, cyclodextrin and graphene oxide also exhibit hydrogen bonding, allowing the phosphorylated cyclodextrin to be composited with graphene oxide nanosheets to form a powder. The introduction of phosphorylated cyclodextrin not only improves the dispersibility of graphene in solution but also provides nucleation sites for subsequent in-situ growth of Zn-MOFs through the cavity structure of cyclodextrin. Then, the cyclodextrin / graphene composite powder is reacted with zinc nitrate hexahydrate and 5-aminoisophthalic acid, utilizing the phosphate groups to bond with Zn... 2+ Through coordination, the amino groups in 5-aminoisophthalic acid can form hydrogen bonds with the hydroxyl groups of cyclodextrin, enhancing the binding ability of Zn-MOF on cyclodextrin / graphene. This allows Zn-MOF to grow in situ on the surface of cyclodextrin / graphene, resulting in a cyclodextrin / graphene / Zn-MOF composite. Finally, the cyclodextrin / graphene / Zn-MOF composite is combined with silicon carbide whiskers and then carbonized at high temperature. During the high-temperature carbonization process, cyclodextrin carbonizes to form porous carbon on the surface of silicon carbide whiskers, and graphene oxide nanosheets are reduced to form graphene nanosheets. Graphene nanosheets have extremely high specific surface area and excellent two-dimensional sheet structure, which can effectively improve the impact resistance and tensile strength of the diced wafers. Meanwhile, cyclodextrin carbonizes at high temperature to form a porous carbon structure, which, together with graphene nanosheets, constructs a carbon-based reinforcing network with hierarchical pores. Zn-MOF decomposes to generate nano-zinc oxide, which is uniformly dispersed on the surface of the carbon network and silicon carbide whiskers, forming a functionalized silicon carbide whisker with a multi-scale gradient interface structure of "silicon carbide whisker-carbon network-nano-zinc oxide." These three components work synergistically in the diced wafer: the silicon carbide whiskers provide rigid framework support, graphene enhances interfacial toughness and stress transfer efficiency, the porous carbon structure absorbs impact energy and alleviates local stress concentration, and the nano-zinc oxide catalyzes the carbonization of the resin matrix during hot pressing and subsequent dicing, further strengthening interfacial bonding and thermal stability. Thus, through a multi-component synergistic reinforcement mechanism, the impact resistance and tensile strength of the diced wafer are significantly improved.

[0016] In a preferred embodiment of this application, the solid-liquid ratio of β-cyclodextrin to phosphoric acid in step S1 is 1:3 (g / ml). This solid-liquid ratio facilitates the full execution of the phosphorylation reaction, ensuring the introduction of sufficient phosphate groups onto the cyclodextrin surface, thus providing ample active sites for subsequent coordination reactions.

[0017] In a preferred embodiment of this application, the mass ratio of phosphorylated cyclodextrin to graphene oxide nanosheets in step S2 is 2:1. This mass ratio facilitates the full coating of the graphene oxide surface by the phosphorylated cyclodextrin, forming a uniform cyclodextrin / graphene composite structure and preventing graphene oxide agglomeration.

[0018] In a preferred embodiment of this application, the mass ratio of zinc nitrate hexahydrate to 5-aminoisophthalic acid in step S3 is 1:1, and the mass ratio of 5-aminoisophthalic acid to cyclodextrin / graphene composite powder is 6:1. This ratio facilitates the uniform nucleation and growth of Zn-MOF on the cyclodextrin / graphene surface, resulting in a structurally regular composite.

[0019] As a preferred embodiment of this application, the mass ratio of the cyclodextrin / graphene / Zn-MOF composite to silicon carbide whiskers in step S4 is 1:10. This mass ratio facilitates the formation of a uniform functionalized coating layer on the surface of the silicon carbide whiskers, ensuring the integrity of the coating while preventing excessive aggregation of the functionalized composite.

[0020] In a preferred embodiment of this application, the diameter of the silicon carbide whiskers is preferably 200–500 nm, more preferably 300–400 nm; the length of the silicon carbide whiskers is preferably 10–15 μm, more preferably 11–14 μm, and most preferably 12–13 μm. By limiting the diameter and length of the silicon carbide whiskers to the above ranges in this invention, more thorough mixing with other components is achieved, and a more suitable aspect ratio is obtained, further improving the toughness of the composite material.

[0021] As a preferred embodiment of this application, the abrasive is one or a mixture of two of the following: diamond, green silicon carbide, boron carbide, white fused alumina, alumina, and brown fused alumina, all with a particle size of 100 mesh. Through the above technical solution, the selection of various abrasives and the optimization of particle size distribution enable better stacking, better filling effect, and lower porosity, allowing for better bonding with resin and improving sharpness and wear resistance.

[0022] As a preferred embodiment of this application, the liquid phenolic resin includes at least one of phenolic resin PR23, phenolic resin PR940, phenolic resin PR55729, phenolic resin PR50232, and phenolic resin PR14170.

[0023] As a preferred embodiment of this application, the powdered phenolic resin includes at least one of phenolic resin PR50099, phenolic resin PR51794, phenolic resin PR13355, phenolic resin PR12987, phenolic resin PR12687, and phenolic resin PR7031A.

[0024] As a preferred embodiment of this application, the cryolite has a particle size of 300-400 mesh. By controlling the particle size of the cryolite within the above range, the bonding force with phenolic resin can be effectively improved, and the dispersibility of the raw materials can be enhanced.

[0025] A second aspect of the present invention provides a method for preparing the wear-resistant and explosion-proof cutting disc, the method comprising the following steps:

[0026] Step 1: Weigh the abrasive, functionalized silicon carbide whiskers, liquid phenolic resin, powdered phenolic resin and cryolite according to the proportions, put them into the mixer and mix them evenly to obtain the mixture.

[0027] Step 2: Preheat the mold to 40-50℃, place a layer of mesh at the bottom of the mold, heat and soften it, then flatten it.

[0028] Step 3: Spread the mixture evenly on the mesh and level it.

[0029] Step 4: Place another layer of mesh on the surface of the mixture and insert the perforated ring;

[0030] Step 5: Close the mold and press it into shape;

[0031] Step 6: After demolding, perform hardening treatment;

[0032] Step 7: After cooling, a wear-resistant and explosion-proof cutting disc is obtained.

[0033] The above technical solution employs a mesh reinforcement structure to form a mesh reinforcement layer inside the cutting disc, further improving its impact resistance. Preheating the mold facilitates uniform heating of the mixture during hot pressing, improving molding quality.

[0034] As a preferred embodiment of this application, the pressing conditions in step 5 are hot pressing at 52°C and 15 MPa for 45 minutes. Through this technical solution, the temperature and pressure conditions allow the phenolic resin to fully melt and flow, while the zinc oxide in the functionalized silicon carbide whiskers acts as a catalyst to promote the condensation reaction between hydroxymethyl groups in the phenolic resin, accelerating cross-linking and curing, forming a carbon layer at the interface, and improving the interfacial bonding strength.

[0035] As a preferred embodiment of this application, the hardening treatment in step 6 involves firing at 70°C for 3 hours, then at 100°C for 4 hours, then at 120°C for 4 hours, then at 160°C for 3 hours, and finally at 190°C for 4 hours. Through the above technical solution, these hardening conditions enable the phenolic resin to fully cross-link and cure, forming a three-dimensional network structure, thereby improving the mechanical strength and heat resistance of the cutting disc.

[0036] The beneficial effects of this invention are:

[0037] This application utilizes the "molecular bridging" effect of phosphorylated cyclodextrin to simultaneously connect the surfaces of graphene oxide, Zn-MOF, and silicon carbide whiskers, achieving uniform composite composition of each component. During high-temperature carbonization, graphene oxide nanosheets are reduced to form graphene nanosheets, and cyclodextrin carbonizes at high temperature to form a porous carbon structure, which, together with the graphene nanosheets, constructs a carbon-based reinforcing network with hierarchical pore characteristics. Zn-MOF decomposes to generate ZnO, and nano-zinc oxide particles are uniformly dispersed on the carbon network and the surface of silicon carbide whiskers, forming a functionalized silicon carbide whisker with a multi-scale gradient interface structure of "silicon carbide whisker—carbon network—nano-zinc oxide." These three components work synergistically in the diced wafer: the high aspect ratio structure of the silicon carbide whiskers forms a three-dimensional reinforcing framework in the resin matrix. Effectively absorbing and dispersing impact energy, the graphene-reinforced interface in the carbon-based network exhibits excellent toughness and high stress transfer efficiency. The porous carbon structure absorbs impact energy and alleviates local stress concentration. ZnO nanoparticles generated by Zn-MOF carbonization are uniformly distributed on the surface of silicon carbide whiskers, catalyzing the carbonization of the resin matrix during hot pressing and subsequent cutting, forming a gradient interface with the phenolic resin carbon layer, and inhibiting crack propagation. The two-dimensional sheet structure of graphene further enhances the toughness of the resin matrix, improving its impact resistance compared to traditional products, and making it less prone to breakage accidents during high-speed cutting.

[0038] This application utilizes cryolite to absorb heat when melting at high cutting temperatures, thus providing lubrication and cooling; the high thermal conductivity of silicon carbide whiskers and graphene promotes rapid heat dissipation; the synergistic effect of these three elements allows the cutting disc to maintain a low operating temperature during high-speed cutting, extending its service life.

[0039] In this application, silicon carbide whiskers, with their high hardness, form a rigid framework within the resin matrix, while graphene, with its high specific surface area, forms a reinforcing network at the interface. The synergistic effect of these two components significantly enhances the resin matrix's grip on the abrasive, effectively suppressing abnormal abrasive shedding during high-speed cutting, thus endowing the cutting disc with excellent wear resistance. Simultaneously, the porous carbon structure formed by β-cyclodextrin carbonization fills the interfacial micro-gaps, and the dense carbon layer formed by ZnO catalysis encapsulates the silicon carbide whiskers and abrasive, jointly constructing a multi-level thermal protection barrier, further enhancing the heat resistance and wear resistance of the resin matrix. This multi-component synergistic effect significantly improves the wear resistance of the cutting disc compared to traditional products. Attached Figure Description

[0040] Figure 1 Comparison chart of cutting time and mass loss rate of cutting discs in Examples 1-3 and Comparative Examples 1-4. Detailed Implementation

[0041] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] Preparation Example 1

[0043] This preparation example provides a method for preparing functionalized silicon carbide whiskers, specifically including the following steps:

[0044] S1. Weigh 15g of β-cyclodextrin and 45mL of concentrated phosphoric acid (85% by mass) and add them to a 200mL reaction vessel. Stir with a magnetic stirrer until a viscous, milky-white liquid is formed. Transfer the mixture to a 90℃ oven and keep it in the oven for 1 hour. After cooling to room temperature, a brownish-yellow liquid is obtained, which is phosphorylated cyclodextrin.

[0045] S2. Disperse the above 8g of phosphorylated cyclodextrin in 300ml of deionized water by ultrasound, add 4g of graphene oxide nanosheets, stir and react, filter and dry to obtain cyclodextrin / graphene composite powder.

[0046] S3. Disperse the above 1g cyclodextrin / graphene composite powder in 100ml water and 200ml DMF, add 6g zinc nitrate hexahydrate and 6g 5-aminoisophthalic acid, stir and react at 115℃ for 18h, filter and dry to obtain cyclodextrin / graphene / Zn-MOF composite.

[0047] S4. 10g of silicon carbide whiskers (diameter 300~400nm, length 12~13μm), 1g of cyclodextrin / graphene / Zn-MOF composite and deionized water were ultrasonically mixed, centrifuged and dried, and then placed in a tube furnace. The temperature was increased to 750℃ at a rate of 5℃ / min under a nitrogen atmosphere and then carbonized at high temperature for 1h to obtain modified silicon carbide whiskers.

[0048] Example 1

[0049] This embodiment provides a wear-resistant and explosion-proof cutting disc and its preparation method, specifically including the following steps:

[0050] Step 1, Preparation of the mixture: Weigh the following components according to the following mass proportions: 12 parts of PR55729 liquid phenolic resin, 10 parts of PR13355 powdered phenolic resin, 75 parts of brown corundum, 12 parts of modified silicon carbide whiskers obtained in Preparation Example 1, and 5 parts of cryolite. Put the above components into a mixer and mix them to obtain the mixture.

[0051] Step 2, Mold Pretreatment: Preheat the mold to 45°C, place a layer of alkali-free glass fiber reinforced mesh at the bottom of the mold, heat and soften it (100°C, 2 seconds), and then flatten it.

[0052] Step 3, spreading the material: Spread the mixture obtained in step 1 evenly on the mesh and smooth it with a scraper to ensure uniform thickness.

[0053] Step 4: Place the upper layer of alkali-free glass fiber reinforced mesh and perforated rings.

[0054] Step 5, Pressing and Molding: Close the mold and place it in a hot press. Press it at 52℃ and 15MPa for 45 minutes to obtain the cut sheet blank.

[0055] Step 6, Hardening treatment: After demolding the cut blank, place it in a hardening furnace for firing. First, fire at 70℃ for 3 hours, then at 100℃ for 4 hours, then at 120℃ for 4 hours, then at 160℃ for 3 hours, and finally at 190℃ for 4 hours.

[0056] Step 7, Cooling: After hardening, cool to room temperature to obtain a wear-resistant and explosion-proof cutting disc.

[0057] Measurements showed that the thickness of the cutting disc prepared in this embodiment was 1.2 mm.

[0058] Example 2

[0059] This embodiment provides a method for preparing a wear-resistant and explosion-proof cutting disc, which differs from Embodiment 1 in that the proportions of each component in step 1 are different. Specifically, it includes the following steps:

[0060] Step 1, Preparation of the mixture: Weigh the following components according to the following mass proportions: 10 parts of PR940 liquid phenolic resin, 15 parts of PR50099 powdered phenolic resin, 60 parts of diamond, 8 parts of functionalized silicon carbide whiskers prepared in Example 1, and 4 parts of cryolite. Put the above components into a mixer and mix them to obtain the mixture.

[0061] The remaining steps are the same as in Example 1.

[0062] Example 3

[0063] This embodiment provides a method for preparing a wear-resistant and explosion-proof cutting disc, which differs from Embodiment 1 in that the proportions of each component in step 1 are different. Specifically, it includes the following steps:

[0064] Step 1: Preparation of the mixture: Weigh the following components according to the following mass proportions: 15 parts of PR50232 liquid phenolic resin, 5 parts of PR12987 powdered phenolic resin, 40 parts of brown fused alumina, 50 parts of white fused alumina, 16 parts of functionalized silicon carbide whiskers prepared in Example 1, and 8 parts of cryolite. Add all the above components to a mixer and mix for 30 minutes to obtain the mixture.

[0065] The remaining steps are the same as in Example 1.

[0066] Comparative Example 1

[0067] This comparative example provides a method for preparing a dicing disc, which differs from Example 1 in that no modified silicon carbide whiskers are added, while the remaining steps are the same as in Example 1.

[0068] Comparative Example 2

[0069] This comparative example provides a method for preparing a cutting disc. The difference from Example 1 is that an equal amount of ceramic crystals are used to replace an equal amount of modified silicon carbide whiskers in the example, while the remaining steps are the same as in Example 1.

[0070] Comparative Example 3

[0071] This comparative example provides a method for preparing diced wafers, which differs from Example 1 in that Zn-MOF is not added during the preparation of modified silicon carbide whiskers. The method specifically includes the following steps:

[0072] In preparing modified silicon carbide whiskers, zinc nitrate hexahydrate and 5-aminoisophthalic acid are not added in step S3. Instead, the cyclodextrin / graphene composite powder obtained in step S2 is directly combined with silicon carbide whiskers and then carbonized at high temperature.

[0073] The remaining steps are the same as in Example 1.

[0074] Comparative Example 4

[0075] This comparative example provides a method for preparing silicon carbide whiskers, which differs from Example 1 in that phosphorylated cyclodextrin is not added during the preparation of modified silicon carbide whiskers. Specifically, it includes the following steps:

[0076] When preparing modified silicon carbide whiskers, step S1 is omitted, and graphene oxide nanosheets are used directly as raw materials. The specific steps are as follows:

[0077] The above 1g graphene composite powder was dispersed in a solvent, and 6g zinc nitrate hexahydrate and 6g 5-aminoisophthalic acid were added. After stirring and reacting, the mixture was filtered and dried to obtain the graphene / Zn-MOF composite.

[0078] 10g of silicon carbide whiskers (diameter 300~400nm, length 12~13μm), 1g of graphene / Zn-MOF composite and deionized water were ultrasonically mixed, centrifuged and dried, and then placed in a tube furnace. The temperature was increased to 750℃ at a rate of 5℃ / min under a nitrogen atmosphere and then carbonized at high temperature for 1h to obtain modified silicon carbide whiskers.

[0079] The remaining steps are the same as in Example 1.

[0080] Performance testing

[0081] The flexural strength, impact toughness, Rockwell hardness and wear resistance of the cutting discs obtained in Examples 1-3 and Comparative Examples 1-4 of this application were tested.

[0082] The bending strength was tested using the three-point bending strength performance test according to the GB / T6569-2006 standard.

[0083] Impact toughness: The impact toughness of the specimens was tested using an XT-300A plastic impact testing machine.

[0084] Rockwell hardness: The HR-150A Rockwell hardness tester measures the hardness of the sample.

[0085] Abrasion resistance test: The sample was fixed on an electric angle grinder with a rotation speed of 11000 r / min, and the steel pipe was then transversely cut. The cutting performance of the abrasive wheel was measured by determining the cutting time and the mass loss of the sample before and after the test. The cross-sectional area of ​​the steel pipe was kept constant. The formula for calculating the mass loss rate (m, %) is shown in the figure below:

[0086] m = (m1 - m2) / m1

[0087] In the formula, m1 is the mass of the cutting disc before the test, in g; m2 is the mass of the cutting disc after the test, in g.

[0088] See results Figure 1

[0089] The performance tests of the examples and comparative examples are shown in Table 1 below.

[0090] Table 1

[0091]

[0092] As shown in Table 1, the performance indicators of Examples 1-3 are significantly better than those of Comparative Examples 1-4. This fully demonstrates the effectiveness of the present invention in improving the mechanical properties, impact toughness, and wear resistance of the cutting disc by introducing modified silicon carbide whiskers and constructing a multi-scale gradient interface structure of "silicon carbide whiskers-carbon network-nano zinc oxide". Specifically, bending strength and impact strength are key indicators for evaluating the structural integrity and explosion-proof performance of the cutting disc. The bending strength of Example 1 reaches 95 MPa, and the impact strength reaches 11.2 kJ / m. 2 In contrast, Comparative Example 1, without the addition of any modified silicon carbide whiskers, exhibited a flexural strength of only 56.5 MPa and an impact strength of only 2.7 kJ / m. 2 The difference between the two is significant. This indicates that traditional cutting discs, consisting solely of phenolic resin and abrasive, have low interfacial bonding strength and lack an effective reinforcing skeleton, making them prone to abrasive shedding or even complete fragmentation during high-speed cutting or impact loads. On the other hand, it also proves that modified silicon carbide whiskers, through their high aspect ratio structure, construct a three-dimensional reinforcing skeleton within the resin matrix, which can effectively absorb and disperse impact energy, thereby significantly improving the impact resistance of the cutting disc.

[0093] Further comparison of Example 1 and Comparative Example 2 shows that simply adding unmodified silicon carbide whiskers can improve mechanical properties to some extent (bending strength increased to 75.4 MPa, impact strength increased to 5.4 kJ / m). 2 However, this is still far inferior to the level of Example 1. The reason is that there is poor interfacial compatibility between the unmodified silicon carbide whiskers and the phenolic resin matrix. Their bonding relies mainly on physical interlocking, which easily leads to stress concentration at the interface, potentially becoming a source of crack initiation under stress. In contrast, the modified silicon carbide whiskers used in Example 1, through the "molecular bridging" effect of phosphorylated cyclodextrin, sequentially composited graphene and Zn-MOF on the whisker surface, and after high-temperature carbonization, formed a gradient interface layer composed of porous carbon, reduced graphene oxide, and dispersed nano-zinc oxide. This structure transforms the simple physical interlocking between the whiskers and resin into a composite interface combining chemical bonding and gradient carbon layer anchoring, significantly improving the interfacial bonding strength and thus increasing the impact strength to 11.2 kJ / m². 2 It is more than twice that of the control group 2, while the quality loss rate drops sharply from 35% to 5.3%, and the wear resistance is fundamentally improved.

[0094] Further analysis of Comparative Examples 3 and 4 clarifies this further. Comparative Example 3 omitted the Zn-MOF component during the preparation of modified silicon carbide whiskers, resulting in an impact strength of only 5.7 kJ / m. 2The mass loss rate was as high as 32%, significantly worse than Example 1. This is because Zn-MOF decomposes to generate nano-zinc oxide during high-temperature carbonization. These nanoparticles are not only uniformly distributed on the whisker surface, but also catalyze the carbonization of phenolic resin during hot pressing and subsequent cutting, forming a dense protective carbon layer at the interface, thereby inhibiting crack propagation and improving interfacial thermal stability. Without Zn-MOF, this catalytic carbonization effect cannot be formed, and the interfacial bonding strength decreases significantly. Comparative Example 4 omitted the phosphorylation modification step of phosphorylated cyclodextrin, disrupting the ordered assembly path from cyclodextrin to graphene to Zn-MOF. This resulted in uneven distribution and severe agglomeration of graphene and Zn-MOF on the whisker surface, making it impossible to form a coherent carbon-reinforced network after carbonization, with an impact strength of only 5.7 kJ / m. 2 The mass loss rate was as high as 31%. This result fully demonstrates that phosphorylated cyclodextrin plays an irreplaceable role as a "molecular bridge" in the construction of the entire multi-level structure, and its absence will lead to the complete loss of the reinforcing effect of functionalized silicon carbide whiskers.

[0095] Furthermore, the hardness of Examples 1-3 were 76 HRB, 78 HRB, and 75 HRB, respectively, all significantly higher than that of Comparative Example 1 (48 HRB), Comparative Example 2 (53 HRB), Comparative Example 3 (55 HRB), and Comparative Example 4 (52 HRB). The hardness of Comparative Examples 1-4 was not higher than 60 HRB, indicating that the addition of unmodified silicon carbide whiskers or incompletely modified silicon carbide whiskers cannot effectively improve the hardness of the resin matrix. The higher hardness of the cutting discs in the Examples compared to the Comparative Examples suggests that the cutting discs in the Examples have a denser structure. The combination of liquid and powdered phenolic resins provides good flowability and wettability, facilitating uniform dispersion of the mixture, while the solid resin provides skeletal support and a cross-linking network, synergistically forming a dense cured body during hot pressing.

[0096] from Figure 1 Regarding the relationship between mass loss rate and cutting time, Examples 1-3 maintained a cutting time of approximately 4 seconds with a mass loss rate of only 4.9%-5.3%, indicating that the cutting discs achieved a significant improvement in wear resistance without sacrificing sharpness. This balance is attributed to the heat absorption and lubrication effect of cryolite during high-temperature cutting, as well as the heat dissipation system formed by the high thermal conductivity of silicon carbide whiskers and graphene. This effectively controls frictional heat during cutting, preventing thermal decomposition of the resin matrix, thus ensuring stable abrasive retention while maintaining good self-sharpening properties. In contrast, Comparative Examples 1-4, although having similar cutting times to the examples, exhibited mass loss rates as high as 31%-36%, indicating that these cutting discs experienced significant abrasive loss during cutting, resulting in extremely short disc lifespans that cannot meet the requirements of practical industrial applications.

[0097] In summary, Table 1 and Figure 1The data fully demonstrate that the present invention, through the multi-scale gradient interface design of modified silicon carbide whiskers, the compounding of liquid and powdered phenolic resins, and the synergistic effect of multiple components such as cryolite lubrication and cooling, has successfully solved the technical problems of insufficient wear resistance, poor impact resistance, and low interface bonding strength of traditional cutting discs. The cutting discs prepared in the examples show excellent performance in terms of bending strength, impact toughness, hardness, and wear resistance, and their comprehensive performance is significantly better than that of the existing technical solutions.

[0098] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A wear-resistant and explosion-proof cutting disc, characterized in that, By weight, it includes the following components: 10-15 parts liquid phenolic resin, 5-15 parts powdered phenolic resin, 60-90 parts abrasive, 8-16 parts modified silicon carbide whiskers, and 4-8 parts cryolite.

2. The cutting disc according to claim 1, characterized in that, The method for preparing the modified silicon carbide whisker phase includes the following steps: S1. After mixing and reacting β-cyclodextrin with concentrated phosphoric acid at 90°C, phosphorylated cyclodextrin is obtained. S2. The phosphorylated cyclodextrin described in step S1 is ultrasonically dispersed in deionized water, graphene oxide nanosheets are added, the mixture is stirred and reacted, then filtered and dried to obtain cyclodextrin / graphene composite powder. S3. Disperse the cyclodextrin / graphene composite powder from step S2 in a solvent, add zinc nitrate hexahydrate and 5-aminoisophthalic acid, stir the reaction, filter and dry to obtain the cyclodextrin / graphene / Zn-MOF composite. S4. The silicon carbide whiskers, cyclodextrin / graphene / Zn-MOF composite and deionized water are ultrasonically mixed, centrifuged and dried, and then placed in a tube furnace for high-temperature carbonization under an inert atmosphere to obtain functionalized silicon carbide whiskers.

3. The cutting disc according to claim 2, characterized in that, The solid-liquid ratio of β-cyclodextrin and phosphate in step S1 is 1:3 (g / ml).

4. The cutting disc according to claim 2, characterized in that, The mass ratio of phosphorylated cyclodextrin to graphene oxide nanosheets in step S2 is 2:

1.

5. The cutting disc according to claim 2, characterized in that, In step S3, the mass ratio of zinc nitrate hexahydrate to 5-aminoisophthalic acid is 1:1, and the mass ratio of 5-aminoisophthalic acid to cyclodextrin / graphene composite powder is 6:

1.

6. The cutting disc according to claim 2, characterized in that, The mass ratio of the cyclodextrin / graphene / Zn-MOF composite and silicon carbide whiskers in step 4 is 1:

10.

7. The cutting disc according to claim 1, characterized in that, The abrasive is one or a mixture of two of the following: diamond, green silicon carbide, boron carbide, white corundum, alumina, and brown corundum.

8. A method for preparing a wear-resistant and explosion-proof cutting disc according to any one of claims 1 to 7, characterized in that, Includes the following steps: Step 1: Weigh the abrasive, modified silicon carbide whiskers, liquid phenolic resin, powdered phenolic resin and cryolite according to the proportions, put them into the mixer and mix them evenly to obtain the mixture. Step 2: Preheat the mold to 40-50℃, place a layer of mesh at the bottom of the mold, heat and soften it, then flatten it. Step 3: Spread the mixture evenly on the mesh and level it. Step 4: Place another layer of mesh on the surface of the mixture and insert the perforated ring; Step 5: Close the mold and perform hot pressing; Step 6: After demolding, perform hardening treatment; Step 7: After cooling, a wear-resistant and explosion-proof cutting disc is obtained.

9. The preparation method according to claim 8, characterized in that, The hot pressing conditions described in step 5 are hot pressing at 52°C and 15MPa, with a holding pressure of 45min.

10. The preparation method according to claim 8, characterized in that, The hardening process described in step 6 is as follows: first, firing at 70°C for 3 hours, then at 100°C for 4 hours, then at 120°C for 4 hours, then at 160°C for 3 hours, and finally at 190°C for 4 hours.

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