Composite production method for metal matrix ceramic composites

Abstract

The present application relates to a kind of composite preparation methods for metal-based ceramic composite material, as follows: one, ceramic preform production: ceramic preform mould is made;After pretreatment, ceramic particles, binder, mixed powder are mixed, filled into mould, twice solidification treatment, and ceramic preform is prepared;Two, metal-based ceramic composite material composite preparation: ceramic preform is fixed in cavity, and metal sheet is placed in the both sides of ceramic preform or between two ceramic preforms;Temperature sensor probe is inserted into cavity;After closing, it is placed in electromagnetic induction coil, and heating is carried out;When metal sheet reaches set temperature, keep warm, when ceramic preform reaches required temperature, electromagnetic induction heating system is closed;Pouring metal liquid, cooling and solidification demoulding;Three, post-processing: quenching and tempering treatment are carried out.The present application solves the problem that ceramic preform and metal liquid temperature difference is too large during metal liquid casting, resulting in poor composite effect, low product yield and unsatisfactory use effect.

Description

Composite preparation method for metal matrix ceramic composites Technical Field

[0001] This invention belongs to the field of wear-resistant materials technology, and in particular relates to a composite preparation method for metal-based ceramic composite materials. Background Technology

[0002] Friction and wear are among the major failure modes of materials and equipment, causing enormous waste of materials and energy every year. As a major industrial producer, my country has a huge annual demand for wear-resistant parts, and improving their service life has become an urgent problem to be solved in recent years. With the development of science and technology and the deepening of industrialization, traditional single wear-resistant materials can no longer meet the needs of modern production. In this context, metal-ceramic composite materials, due to their excellent wear resistance, high strength, and high toughness, have wide applications in the automotive, defense, and aerospace industries, and have become a research hotspot for researchers and manufacturers worldwide.

[0003] Current research on the preparation of metal-based ceramic composites mainly focuses on improving the wettability between metal and ceramic and molding methods for molten metal casting. However, in the molten metal casting process, due to the significant difference in the coefficients of thermal expansion between the molten metal and the ceramic preform, the large temperature difference between them is largely ignored or underestimated. Furthermore, the coefficient of thermal expansion of ceramic particles also changes considerably around 700℃. Therefore, the large temperature difference during casting can lead to fracture and collapse of the ceramic preform, resulting in a low yield of metal-ceramic composite preforms. Simultaneously, the undercooling of the ceramic preform during molten metal casting easily generates defects such as microcracks and inclusions, causing the actual performance of the composite product to differ significantly from theoretical research.

[0004] Chinese Patent Publication No. CN104148614A discloses a method for preparing a metal-ceramic mesh composite reinforced liner. The method involves mixing metal-ceramic materials with a binder, filling the cavity of a press mesh mold, pressing and demolding, vacuum sintering, and cooling to obtain a metal-ceramic mesh preform. This preform is then sandblasted, preheated, and fixed to the surface of a grinding disc liner casting mold cavity. Finally, a wear-resistant alloy material solution is cast to obtain the composite reinforced grinding disc liner. However, this method only solves the problem of the preform being difficult to disperse during the casting process. Chinese Patent Publication No. CN114871382A discloses a method for preparing a micro-powder-coated hexagonal prism-shaped ZTA / Fe composite material. The method involves uniformly mixing ceramic micro-powder and a binder, adding ZTA ceramic particles and mixing thoroughly, placing the mixture into a pre-prepared hexagonal prism-shaped lost foam mold for drying, obtaining a hexagonal prism-shaped honeycomb ZTA / Fe composite material preform lost foam mold, attaching an EPS pattern to the mold, coating the surface with refractory material, pouring high-chromium cast iron molten metal under negative pressure, and cooling to obtain a ceramic micro-powder-coated hexagonal prism-shaped honeycomb ZTA / Fe composite material. This method employs lost foam technology and improves the wettability of ZTA with the molten metal by adding ceramic micro-powder, but takes relatively few measures regarding the composite process. Chinese Patent Publication No. CN104399930A discloses a method for centrifugally casting a grinding roller of a vertical mill made of ceramic-metal honeycomb composite material. This method involves filling a mold with ceramic particles, a pore-forming agent, and a binder to obtain a ceramic particle preform with inlaid pillars, inlaid holes, and bosses on the sand mold contact surface. The inlaid pillars of two ceramic particle preforms are then embedded in the inlaid holes and spliced ​​together. Several spliced ​​ceramic particle preforms are fixed in a metal mold. After preheating the entire metal mold, it is fixed in a centrifugal casting device, where high-temperature molten metal is poured. After heat treatment, a grinding roller of ceramic-metal honeycomb composite material is obtained. However, this method only solves the problem of splicing small ceramic preforms and allows defective small pieces to be replaced during the molding process, without fundamentally improving the defect problem. Chinese Patent Publication No. CN111974972A discloses a ceramic-metal composite wear-resistant material and its preparation method. The method involves pressing a preheated ceramic preform and a molten metal together in a mold, followed by cooling and tempering. However, this method only vaguely mentions preheating the ceramic preform to reduce the temperature difference between the ceramic and the metal, and using a pressure-based composite molding method. It does not actually solve the problem of the large temperature difference between the ceramic preform and the molten metal during the casting process.

[0005] In summary, current research on metal-ceramic composite technology focuses primarily on improving the wettability between ceramics and metals. However, there has been a lack of specific research on how to address the significant difference in thermal expansion coefficients between the molten metal and the ceramic preform, particularly during the molten metal casting process. This lack of research has resulted in unsatisfactory yield and performance of the composite products due to the large temperature difference between the ceramic preform and the molten metal. Summary of the Invention

[0006] To address the problems existing in the prior art, this invention provides a method for preparing metal-based ceramic composite materials. This method specifically solves the problem that excessive temperature difference between the ceramic preform and the molten metal during the metal casting process leads to poor composite effect, low yield of composite products, and unsatisfactory performance.

[0007] This invention is achieved through a composite preparation method for metal-based ceramic composite materials, with the following specific steps:

[0008] Step 1: Fabrication of Ceramic Precast Body

[0009] Step 11: Make the ceramic preform mold;

[0010] Step 12: Mix the pretreated ceramic particles, binder, and mixed powder evenly, fill the ceramic preform mold, and cure twice to obtain a ceramic preform with fixed structures at both ends;

[0011] Step 2: Composite preparation of metal-based ceramic composite materials

[0012] Step 21: Fix the ceramic preform made in Step 1 into the cavity of the sand casting mold with clips, and place metal sheets on both sides of the ceramic preform or between two ceramic preforms.

[0013] Step 22: The sand box has a pre-drilled temperature measurement hole. Insert the probe of the temperature sensor into the cavity.

[0014] Step 23: After the sand box is closed, place the sand box into the electromagnetic induction coil; turn on the electromagnetic induction heating system, and use electromagnetic induction to cut the metal sheets and clips between the ceramic preforms to heat the ceramic preforms.

[0015] Step 24: Use a temperature sensor to monitor the temperature of the metal sheet and ceramic preform inside the cavity. When the metal sheet reaches the set temperature, keep it warm. When the ceramic preform reaches the required temperature, turn off the electromagnetic induction heating system.

[0016] Step 25: Pour the molten metal into the mold cavity, cool and solidify, and demold.

[0017] Step 3: Post-processing of metal-based ceramic composite materials

[0018] Step 31: Quench the metal-based ceramic composite material prepared in Step 2.

[0019] Step 32: Temper the quenched metal-based ceramic composite material.

[0020] Preferably, in step 11, the mold is honeycomb-shaped, and the honeycomb shape is circular or regular hexagonal; the mold has a fixing structure at both ends, and the fixing structure is double-ear-shaped or figure-eight-shaped.

[0021] Preferably, in step 12, the ceramic particles are one or a mixture of several of the following in any proportion: zirconium corundum, alumina, silicon nitride, titanium nitride, silicon carbide, boron carbide, titanium carbide, titanium boride, and tungsten carbide.

[0022] More preferably, the pretreatment of ceramic particles mainly involves ball milling ceramic particles with a particle size range of 2-4 mm, and then applying a thermal spray powder with a particle size of 500-600 mesh, consisting of Al2O3 or B4C or a mixture of Al2O3 and B4C powders, wherein the weight of the thermal spray powder is 1-3% of the weight of the ceramic particles to be sprayed.

[0023] Preferably, in step 12, the binder is an aqueous solution of sodium silicate, and the amount of binder added is 4 to 10% of the total weight of the pretreated ceramic particles.

[0024] Preferably, in step 12, the mixed powder is a mixture of Al2O3, B4C and Fe3O powders, wherein the particle size of Al2O3 and B4C powders is 600-800 mesh, the particle size of Fe3O powder is 800-1000 mesh, the weight ratio of Al2O3:B4C:Fe3O is 1:1:3 to 1:1:8, and the total amount of mixed powder added is 2-10% of the total weight of the pretreated ceramic particles.

[0025] Preferably, in step 21, the shape of the clip is U-shaped or L-shaped, which can ensure the fixation of the ceramic preform and assist in heating the ceramic preform when the electromagnetic induction heating system is turned on; the gap between two adjacent ceramic preforms is 10-15mm, the metal sheet is made of Q235 thin steel plate, the distance between the metal sheet and the edge of the ceramic preform is 2-6mm, it is 10-15mm higher than the ceramic preform, and both ends are 10-20mm longer than the ceramic preform.

[0026] Preferably, in step 22, a temperature sensor probe is inserted into the cavity, and the temperature of the metal sheet and ceramic preform inside the cavity is measured by different probes.

[0027] Preferably, in step 23, the electromagnetic induction coil is placed on a trolley that can move left and right, and the opening and closing of the electromagnetic induction coil is controlled by the movement of the trolley. The heating power of the electromagnetic induction coil is selected between 5-10KW.

[0028] Preferably, in step 24, after the electromagnetic induction heating system is turned on, the temperature of the metal sheet inside the cavity is monitored by a temperature sensor. When the measured temperature of the metal sheet is 900-1000℃, the system enters the heat preservation state. The temperature of the ceramic preform is monitored by a temperature sensor. When the temperature of the ceramic preform reaches 700-800℃, the electromagnetic induction heating system is turned off, the electromagnetic induction coil is turned on, and the casting is prepared.

[0029] Preferably, in step 25, the molten metal is high-chromium cast iron, high-manganese steel, or high-alloy steel, the pouring temperature is controlled at 1500–1580°C, and the pouring speed is controlled at 6–12 kg / s.

[0030] Preferably, in step 31, the quenching process is as follows: the metal-based ceramic composite material is placed in a heat treatment furnace and heated to 960-1050°C at a heating rate of 30-50°C / h, with step-by-step heat preservation in between, and then air-cooled to room temperature.

[0031] Preferably, in step 32, the tempering process is as follows: the quenched metal-based ceramic composite material is further tempered in a heat treatment furnace at a tempering temperature of 280-600°C for 4-6 hours, and then air-cooled to room temperature.

[0032] The advantages and positive effects of this invention are:

[0033] 1. This invention designs the ceramic preform with fixing structures at both ends and uses U-shaped or L-shaped clips for auxiliary fixing. On the one hand, it is beneficial to fix the ceramic preform in the cavity, which improves the inconvenience of operation in traditional fixing methods. On the other hand, it can assist in preheating the ceramic preform during electromagnetic induction heating, thereby improving heating efficiency.

[0034] 2. This invention utilizes a specific electromagnetic induction heating device and inserts metal sheets between ceramic preforms to heat the ceramic preforms through thermal radiation. This ensures that the ceramic preforms maintain a constant high temperature during the molten metal casting process, reducing the temperature difference between the ceramic preforms and the molten metal. This effectively maintains the activity of the ceramic preforms and the temperature stability during the molten metal casting process, thereby promoting the bonding between ceramic particles and molten metal. It also improves problems such as the collapse and fracture of the ceramic preforms during casting and mitigates defects such as microcracks and inclusions caused by the large temperature difference between the molten metal and the ceramic preforms, significantly increasing the yield of metal-based ceramic composite materials.

[0035] 3. By using a temperature sensor, this invention can more accurately monitor the temperature of the ceramic preform inside the cavity, which is beneficial for selecting the appropriate casting time and temperature.

[0036] 4. This invention uses electromagnetic induction heating, resulting in faster heating speed and higher heating efficiency.

[0037] 5. This invention effectively ensures the porosity between ceramic particles in the ceramic preform by screening the ceramic particles, allowing the molten metal to better penetrate into the ceramic preform and completely encapsulate the ceramic particles. The grinding process removes the sharp edges of the ceramic particles, preventing stress concentration that could lead to particle breakage and peeling during subsequent use. The powder coating process effectively achieves metallurgical bonding between the ceramic particles and the high-temperature molten metal through the mixed powder, forming a transitional bonding layer after cooling. This significantly improves the bonding force between the metal and ceramic, effectively solving the problem of traditional metal-based ceramic particles only being mechanically bonded and prone to peeling and failure during use.

[0038] 6. The addition of a powder composed of Al2O3, B4C, and Fe3O to the ceramic preform of the present invention can actively help the molten metal to coat the ceramic particles, and can also effectively promote the formation of a metallurgical bonding transition layer between the molten metal and the ceramic particles; moreover, the preform undergoes two curing processes during its fabrication, which significantly improves the strength of the preform itself, preventing it from collapsing and breaking during the pouring of the molten metal, and effectively ensuring that the ceramic particles are dispersed in their original positions, resulting in excellent wear resistance. Attached Figure Description

[0039] Figure 1 is a schematic diagram of an arrangement structure in which metal sheets are inserted between ceramic preforms according to the present invention;

[0040] Figure 2 is a schematic diagram of another arrangement structure of inserting metal sheets between ceramic preforms according to the present invention;

[0041] Figure 3 is a schematic diagram of the sand box and electromagnetic induction heating system of the present invention;

[0042] Figure 4 is a schematic diagram of the sand box of the present invention undergoing electromagnetic induction heating;

[0043] Figure 5 is a photograph showing the composite effect of the metal-based ceramic composite material prepared in Example 1 of the present invention after polishing.

[0044] Among them: 11. Metal sheet; 12. Ceramic preform; 21. Electromagnetic induction coil; 22. Sand box; 23. Pour gate; 24. Temperature sensor; 25. Trolley. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of this invention clearer, and to further understand the invention's content, features, and effects, the following specific embodiments are provided to further illustrate the invention in detail. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of the invention.

[0046] This embodiment provides a method for preparing metal-based ceramic composite materials, the specific steps of which are as follows:

[0047] Step 1: Fabrication of Ceramic Precast Body

[0048] Step 11: Make the ceramic preform mold;

[0049] Step 12: Mix the pretreated ceramic particles, binder, and mixed powder evenly, fill the ceramic preform mold, and cure twice to obtain a ceramic preform with fixed structures at both ends;

[0050] Step 2: Composite preparation of metal-based ceramic composite materials

[0051] Step 21: Fix the ceramic preform made in Step 1 into the cavity of the sand casting mold with clips, and place metal sheets on both sides of the ceramic preform or between two ceramic preforms.

[0052] Step 22: The sand box has a pre-drilled temperature measurement hole. Insert the probe of the temperature sensor into the cavity.

[0053] Step 23: After the sand box is closed, place the sand box into the electromagnetic induction coil; turn on the electromagnetic induction heating system, and use electromagnetic induction to cut the metal sheets and clips between the ceramic preforms to heat the ceramic preforms.

[0054] Step 24: Use a temperature sensor to monitor the temperature of the metal sheet and ceramic preform inside the cavity. When the metal sheet reaches the set temperature, keep it warm. When the ceramic preform reaches the required temperature, turn off the electromagnetic induction heating system.

[0055] Step 25: Pour the molten metal into the mold cavity, cool and solidify, and demold.

[0056] Step 3: Post-processing of metal-based ceramic composite materials

[0057] Step 31: Quench the metal-based ceramic composite material prepared in Step 2.

[0058] Step 32: Temper the quenched metal-based ceramic composite material.

[0059] In step 11, the mold is honeycomb-shaped, and the honeycomb shape is circular or regular hexagonal; the mold has a fixing structure at both ends, which can be double-ear-shaped or figure-eight-shaped, mainly to facilitate the fixing of the ceramic preform in the cavity.

[0060] In step 12, the ceramic particles are one or a mixture of several of the following in any proportion: zirconium corundum, alumina, silicon nitride, titanium nitride, silicon carbide, boron carbide, titanium carbide, titanium boride, and tungsten carbide. The pretreatment of the ceramic particles mainly involves ball milling ceramic particles with a particle size range of 2-4 mm, followed by surface thermal spraying with Al2O3 or B4C powder with a particle size of 500-600 mesh, or a mixture of Al2O3 and B4C powders. The weight of the thermal spraying powder is 1-3% of the weight of the ceramic particles to be sprayed. When the thermal spraying powder is a mixture of Al2O3 and B4C powders, the weight ratio of Al2O3 to B4C is 1:2 to 1:1.

[0061] In step 12, the binder is an aqueous solution of sodium silicate, and the amount of binder added is 4 to 10% of the total weight of the pretreated ceramic particles.

[0062] In step 12, the mixed powder is a mixture of Al2O3, B4C and Fe3O powders, wherein the particle size of Al2O3 and B4C powders is 600-800 mesh, the particle size of Fe3O powder is 800-1000 mesh, the weight ratio of Al2O3:B4C:Fe3O is 1:1:3 to 1:1:8, and the total amount of mixed powder added is 2-10% of the total weight of the pretreated ceramic particles.

[0063] In step 21, the clips are U-shaped or L-shaped, which can ensure the fixation of the ceramic preform and assist in heating the ceramic preform when the electromagnetic induction heating system is turned on. The gap between two adjacent ceramic preforms is 10-15mm. The metal sheet inserted between the ceramic preforms is made of Q235 thin steel plate. The distance between the metal sheet and the edge of the ceramic preform is 2-6mm. The metal sheet is 10-15mm higher than the ceramic preform and 10-20mm longer than the ceramic preform at both ends.

[0064] In step 22, a temperature sensor probe is inserted into the cavity, and the temperature of the metal sheet and ceramic preform inside the cavity is measured by different probes.

[0065] In step 23, the electromagnetic induction coil is placed on a trolley that can move left and right. The opening and closing of the electromagnetic induction coil is controlled by the movement of the trolley. The heating power of the electromagnetic induction coil is selected between 5-10KW.

[0066] In step 24, after the electromagnetic induction heating system is turned on, the temperature of the metal sheet in the cavity is monitored by a temperature sensor. When the temperature of the metal sheet is around 900-1000℃, the set temperature is reached and the system enters the heat preservation state. The temperature of the ceramic preform is monitored by a temperature sensor. When the temperature of the ceramic preform reaches 700-800℃, the electromagnetic induction heating system is turned off and the electromagnetic induction coil is turned on to prepare for casting.

[0067] In step 25, the molten metal is high-chromium cast iron, high-manganese steel, or high-alloy steel, and the pouring temperature is controlled at 1500–1580℃, while the pouring speed is controlled at 6–12 kg / s.

[0068] In step 31, the quenching process is as follows: the metal-based ceramic composite material is placed in a heat treatment furnace and heated to 960-1050°C at a heating rate of 30-50°C / h, with step-by-step heat preservation in between, and then air-cooled to room temperature.

[0069] In step 32, the tempering process is as follows: the quenched metal-based ceramic composite material is further tempered in a heat treatment furnace at a tempering temperature of 280-600℃ for 4-6 hours, and then air-cooled to room temperature.

[0070] To better understand the above embodiments of the present invention, further explanation is provided below with reference to specific examples.

[0071] Example 1

[0072] This embodiment 1 provides a composite preparation method for metal-based ceramic composite materials, the specific steps of which are as follows:

[0073] Step 1: Fabrication of Ceramic Precast Body

[0074] Step 11: Make a ceramic preform mold. The mold is honeycomb-shaped with circular honeycomb sections and double-ear-shaped fixing structures at both ends.

[0075] Step 12: Zirconium corundum ceramic particles with a particle size of 2.5-3 mm and silicon carbide ceramic particles are mixed at a weight ratio of 1:1. After ball milling, the surface is thermally sprayed with Al2O3 and B4C with a particle size of 500 mesh and a weight ratio of 1%. Then, 100 parts by weight of the pretreated mixed ceramic particles, 5 parts of sodium silicate aqueous solution and 5 parts of mixed powder (Al2O3:B4C:Fe3O weight ratio of 1:1:3) are weighed, mixed evenly, and filled into a ceramic preform mold. After preliminary curing, it is heated and pressurized for curing. After demolding, a ceramic preform with a double-ear-shaped fixing structure at both ends is obtained.

[0076] Step 2: Composite preparation of metal-based ceramic composite materials

[0077] Step 21: Use U-shaped clips to fix several ceramic preforms prepared in Step 1 into the sand casting mold cavity, with a gap of 10mm between each pair of ceramic preforms. At the same time, insert Q235 thin steel plates between each pair of ceramic preforms as shown in Figure 1. The distance between the thin steel plates and the ceramic preforms on both sides is about 5mm, and each end is 10mm longer than the ceramic preform.

[0078] Step 22: Insert the temperature sensor probe into the cavity through the pre-reserved temperature measurement hole in the sand box. The probe measures the temperature of the ceramic preform and the Q235 thin steel plate respectively.

[0079] Step 23: After closing the box, transport the sand box to the casting area, control the trolley 25 in Figure 3 to move to both sides, turn on the electromagnetic induction coil 21, place the sand box 22 in the designated area, and then operate the trolley to close the electromagnetic induction coil, as shown in Figure 4; turn on the electromagnetic induction heating controller, the electromagnetic field generates heat through the thin steel plate and U-shaped clips placed in the cutting cavity, and radiates to the ceramic preform to achieve heating of the ceramic preform;

[0080] Step 24: The temperature of the thin steel plate is monitored by temperature sensor 24. When the temperature of the thin steel plate reaches 1000℃, heat preservation is performed. At the same time, the temperature of the ceramic preform in the cavity is monitored by temperature sensor. When the temperature of the ceramic preform reaches 800℃, electromagnetic induction heating is stopped and the electromagnetic induction coil is turned on.

[0081] Step 25: Pour the molten high-chromium cast iron into the mold cavity through the pouring gate 23. The pouring temperature is 1500-1520℃ and the pouring speed is controlled at 10kg / s. After pouring, cool and solidify and demold.

[0082] Step 3: Post-processing of metal-based ceramic composite materials

[0083] Step 31: Place the metal-based ceramic composite material prepared in Step 2 into a heat treatment furnace, heat it to 500℃ at a heating rate of 30℃ / h, hold it at that temperature for 0.5h, then heat it to 600℃ at a heating rate of 30℃ / h, hold it at that temperature for 0.5h, then heat it to 1050℃ at a heating rate of 35℃ / h, hold it at that temperature for 4h, and then air cool it to room temperature.

[0084] Step 32: The metal-based ceramic composite material after quenching in step 31 is heated to 600℃ at a heating rate of 30℃ / h, held at that temperature for 4h, and then air-cooled to room temperature to obtain a metal-based ceramic composite material with excellent performance, as shown in Figure 5.

[0085] Example 2

[0086] This embodiment 2 provides a composite preparation method for metal-based ceramic composite materials, the specific steps of which are as follows:

[0087] Step 1: Fabrication of Ceramic Precast Body

[0088] Step 11: Make a ceramic preform mold. The mold is honeycomb-shaped, with the honeycomb being a regular hexagon, and both ends are designed with figure-eight-shaped fixing structures.

[0089] Step 12: Zirconium corundum ceramic particles, silicon carbide ceramic particles, and silicon nitride ceramic particles with a particle size of 3-3.5 mm are mixed in a weight ratio of 6:3:1. After ball milling, the surface is thermally sprayed with Al2O3 and B4C with a particle size of 550 mesh and a weight percentage of 2%. Then, 100 parts by weight of the pretreated mixed ceramic particles, 8 parts of sodium silicate aqueous solution, and 6 parts of mixed powder (Al2O3:B4C:Fe3O weight ratio of 1:1:4) are weighed and mixed evenly. The mixture is then filled into a ceramic preform mold. After preliminary curing, it is heated and pressurized for curing. After demolding, a ceramic preform with figure-eight fixed structures at both ends is obtained.

[0090] Step 2: Composite preparation of metal-based ceramic composite materials

[0091] Step 21: Use L-shaped clips to fix several ceramic preforms prepared in Step 1 into the sand casting mold cavity, with a gap of 12mm between each pair of ceramic preforms. At the same time, insert a Q235 thin steel plate between each pair of ceramic preforms as shown in Figure 1. The distance between the thin steel plate and the ceramic preforms on both sides is about 6mm, and each end is 15mm longer than the ceramic preform.

[0092] Step 22: Insert the temperature sensor probe into the cavity through the pre-reserved temperature measurement hole in the sand box. The probe measures the temperature of the ceramic preform and the Q235 thin steel plate respectively.

[0093] Step 23: After the sand box is closed, transport the sand box to the casting area, control the trolley 25 in Figure 3 to move to both sides, turn on the electromagnetic induction coil 21, place the sand box 22 in the designated area, and then operate the trolley to close the electromagnetic induction coil, as shown in Figure 4; turn on the electromagnetic induction heating controller, the electromagnetic field generates heat through the thin steel plate and L-shaped clips placed in the cutting cavity, and radiates to the ceramic preform to achieve heating of the ceramic preform;

[0094] Step 24: The temperature of the thin steel plate is monitored by temperature sensor 24. When the temperature of the thin steel plate reaches 900°C, heat preservation is performed. At the same time, the temperature of the ceramic preform in the cavity is monitored by temperature sensor. When the temperature of the ceramic preform reaches 700°C, electromagnetic induction heating is stopped and the electromagnetic induction coil is turned on.

[0095] Step 25: Pour the molten high-manganese steel into the mold cavity through the pouring port 23. The pouring temperature is 1520-1550℃ and the pouring speed is controlled at 12kg / s. After pouring, cool and solidify, and demold.

[0096] Step 3: Post-processing of metal-based ceramic composite materials

[0097] Step 31: Place the metal-based ceramic composite material prepared in Step 2 into a heat treatment furnace, heat it to 400℃ at a heating rate of 35℃ / h, hold it at that temperature for 0.5h, then heat it to 600℃ at a heating rate of 35℃ / h, hold it at that temperature for 0.5h, then heat it to 1000℃ at a heating rate of 40℃ / h, hold it at that temperature for 5h, and then air cool it to room temperature.

[0098] Step 32: The metal-based ceramic composite material after quenching in step 31 is heated to 600℃ at a heating rate of 40℃ / h, held at that temperature for 5h, and then air-cooled to room temperature to obtain a metal-based ceramic composite material with excellent performance.

[0099] Example 3

[0100] This embodiment 3 provides a method for preparing metal-based ceramic composite materials, the specific steps of which are as follows:

[0101] Step 1: Fabrication of Ceramic Precast Body

[0102] Step 11: Make a ceramic preform mold. The mold is honeycomb-shaped with circular honeycomb sections and double-ear-shaped fixing structures at both ends.

[0103] Step 12: Alumina ceramic particles, silicon carbide ceramic particles, and carbon nitride ceramic particles with a particle size of 3.5-4 mm are mixed evenly in a weight ratio of 5:3:2. The mixture is then ball-milled, and the surface is thermally sprayed with B4C with a particle size of 600 mesh and a weight percentage of 3%. Then, 100 parts by weight of the pretreated mixed ceramic particles, 10 parts of sodium silicate aqueous solution, and 8 parts of mixed powder (Al2O3:B4C:Fe3O weight ratio of 1:1:6) are weighed, mixed evenly, and filled into a ceramic preform mold. After preliminary curing, it is heated and pressurized for curing. After demolding, a ceramic preform with a double-ear-shaped fixing structure at both ends is obtained.

[0104] Step 2: Composite preparation of metal-based ceramic composite materials

[0105] Step 21: Use T-shaped clips to fix several ceramic preforms prepared in Step 1 into the sand casting mold cavity, with a gap of 15mm between each pair of ceramic preforms. At the same time, insert Q235 thin steel plates on both sides of each ceramic preform as shown in Figure 2, with the thin steel plates 2mm away from the ceramic preform and each end extending 20mm beyond the ceramic preform.

[0106] Step 22: Insert the temperature sensor probe into the cavity through the pre-reserved temperature measurement hole in the sand box. The probe measures the temperature of the ceramic preform and the Q235 thin steel plate respectively.

[0107] Step 23: After closing the box, transport the sand box to the casting area, control the trolley 25 in Figure 3 to move to both sides, turn on the electromagnetic induction coil 21, place the sand box 22 in the designated area, and then operate the trolley to close the electromagnetic induction coil, as shown in Figure 4; turn on the electromagnetic induction heating controller, the electromagnetic field generates heat through the thin steel plate and T-shaped clips placed in the cutting cavity, and radiates to the ceramic preform to achieve heating of the ceramic preform;

[0108] Step 24: The temperature of the thin steel plate is monitored by temperature sensor 24. When the temperature of the thin steel plate reaches 800℃, heat preservation is performed. At the same time, the temperature of the ceramic preform in the cavity is monitored by temperature sensor. When the temperature of the ceramic preform reaches 600℃, electromagnetic induction heating is stopped and the electromagnetic induction coil is turned on.

[0109] Step 25: Pour the molten high-alloy steel into the mold cavity through the pouring port 23. The pouring temperature is 1550-1580℃ and the pouring speed is controlled at 8kg / s. After pouring, cool and solidify, and demold.

[0110] Step 3: Post-processing of metal-based ceramic composite materials

[0111] Step 31: Place the metal-based ceramic composite material prepared in Step 2 into a heat treatment furnace, heat it to 300℃ at a heating rate of 40℃ / h, hold it at that temperature for 1h, then heat it to 500℃ at a heating rate of 40℃ / h, hold it at that temperature for 1h, then heat it to 1020℃ at a heating rate of 45℃ / h, hold it at that temperature for 4h, and then air cool it to room temperature.

[0112] Step 32: The metal-based ceramic composite material after quenching in step 31 is heated to 500℃ at a heating rate of 35℃ / h, held at that temperature for 6h, and then air-cooled to room temperature to obtain a metal-based ceramic composite material with excellent performance.

[0113] This invention primarily utilizes a specific electromagnetic induction heating device and inserts metal sheets between ceramic preforms to heat the ceramic preforms through thermal radiation. This ensures that the ceramic preforms maintain a constant high temperature during the molten metal pouring process, reducing the temperature difference between the ceramic preforms and the molten metal. This effectively maintains the activity of the ceramic preforms and the temperature stability during the molten metal pouring process, thereby promoting the bonding between ceramic particles and molten metal. It also improves problems such as the collapse and fracture of the ceramic preforms during the pouring process and mitigates defects such as microcracks and inclusions caused by the large temperature difference between the molten metal and the ceramic preforms, significantly increasing the yield of metal-based ceramic composite materials.

[0114] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention shall fall within the scope of the technical solution of the present invention.

Claims

1. A method for preparing metal-based ceramic composite materials, characterized in that, The specific steps are as follows: Step 1: Production of ceramic preforms Step 11: Make a ceramic preform mold; Step 12: Mix the pretreated ceramic particles, binder, and mixed powder evenly, fill the ceramic preform mold, and cure twice to obtain a ceramic preform with fixed structures at both ends; Step 2: Composite preparation of metal-based ceramic composites Step 21: Fix the ceramic preform made in Step 1 into the cavity of the sand casting mold with clips, and place metal sheets on both sides of the ceramic preform or between two ceramic preforms; Step 22: The sand mold has a pre-reserved temperature measuring hole, and the probe of the temperature sensor is inserted into the cavity; Step 23: After closing the mold, place the sand mold into the electromagnetic induction line. Step 24: Activate the electromagnetic induction heating system to heat the ceramic preforms by electromagnetically cutting the metal sheets and clips between them; Step 25: Use a temperature sensor to monitor the temperature of the metal sheets and ceramic preforms in the cavity. When the metal sheets reach the set temperature, maintain the temperature. When the ceramic preforms reach the required temperature, turn off the electromagnetic induction heating system; Step 26: Pour the molten metal into the cavity, cool and solidify, and demold; Step 3: Post-processing of metal-based ceramic composite materials Step 31: Quench the metal-based ceramic composite materials produced in Step 2; Step 32: Temper the quenched metal-based ceramic composite materials.

2. The method for preparing metal-based ceramic composite materials according to claim 1, characterized in that, In step 11, the mold is honeycomb-shaped, and the honeycomb shape is circular or regular hexagonal; the mold has a fixing structure at both ends, and the fixing structure is double-ear-shaped or figure-eight-shaped.

3. The method for preparing metal-based ceramic composite materials according to claim 1, characterized in that, In step 12, the ceramic particles are one or a mixture of several of the following in any proportion: zirconium corundum, alumina, silicon nitride, titanium nitride, silicon carbide, boron carbide, titanium carbide, titanium boride, and tungsten carbide.

4. The method for preparing metal-based ceramic composite materials according to claim 3, characterized in that, The pretreatment of ceramic particles mainly involves ball milling ceramic particles with a particle size range of 2-4 mm, followed by surface thermal spraying of Al2O3 or B4C or a mixture of Al2O3 and B4C powders with a particle size of 500-600 mesh. The weight of the thermal spraying powder is 1-3% of the weight of the ceramic particles to be sprayed.

5. The method for preparing metal-based ceramic composite materials according to claim 1, characterized in that, In step 12, the binder is an aqueous solution of sodium silicate, and the amount of binder added is 4 to 10% of the total weight of the pretreated ceramic particles.

6. The method for preparing metal-based ceramic composite materials according to claim 1, characterized in that, In step 12, the mixed powder is a mixture of Al2O3, B4C and Fe3O powders, wherein the particle size of Al2O3 and B4C powders is 600-800 mesh, the particle size of Fe3O powder is 800-1000 mesh, the weight ratio of Al2O3:B4C:Fe3O is 1:1:3 to 1:1:8, and the total amount of mixed powder added is 2-10% of the total weight of the pretreated ceramic particles.

7. The method for preparing metal-based ceramic composite materials according to claim 1, characterized in that, In step 21, the shape of the clip is U-shaped or L-shaped; the gap between two adjacent ceramic preforms is 10-15mm; the metal sheet is made of Q235 thin steel plate; the distance between the metal sheet and the edge of the ceramic preform is 2-6mm; the metal sheet is 10-15mm higher than the ceramic preform; and both ends are 10-20mm longer than the ceramic preform.

8. The method for preparing metal-based ceramic composite materials according to claim 1, characterized in that, In step 22, a temperature sensor probe is inserted into the cavity, and the temperature of the metal sheet and ceramic preform inside the cavity is measured by different probes.

9. The method for preparing metal-based ceramic composite materials according to claim 1, characterized in that, In step 23, the electromagnetic induction coil is placed on a trolley that can move left and right. The opening and closing of the electromagnetic induction coil is controlled by the movement of the trolley. The heating power of the electromagnetic induction coil is selected between 5-10KW.

10. The method for preparing metal-based ceramic composite materials according to claim 1, characterized in that, In step 24, after the electromagnetic induction heating system is turned on, the temperature of the metal sheet in the cavity is monitored by a temperature sensor. When the measured temperature of the metal sheet is 900-1000℃, the system enters the heat preservation state. The temperature of the ceramic preform is monitored by a temperature sensor. When the temperature of the ceramic preform reaches 700-800℃, the electromagnetic induction heating system is turned off, the electromagnetic induction coil is turned on, and the casting is prepared.

11. The method for preparing metal-based ceramic composite materials according to claim 1, characterized in that, In step 25, the molten metal is high-chromium cast iron, high-manganese steel, or high-alloy steel, and the pouring temperature is controlled at 1500-1580℃, while the pouring speed is controlled at 6-12 kg / s.

12. The method for preparing metal-based ceramic composite materials according to claim 1, characterized in that, In step 31, the quenching process is as follows: the metal-based ceramic composite material is placed in a heat treatment furnace and heated to 960-1050°C at a heating rate of 30-50°C / h, with step-by-step heat preservation in between, and then air-cooled to room temperature.

13. The method for preparing metal-based ceramic composite materials according to claim 1, characterized in that, In step 32, the tempering process is as follows: the quenched metal-based ceramic composite material is further tempered in a heat treatment furnace at a tempering temperature of 280-600℃ for 4-6 hours, and then air-cooled to room temperature.

14. A metal-based ceramic composite material, characterized in that, It is prepared by the composite preparation method for metal matrix ceramic composite materials according to any one of claims 1-13.

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