A low-cost ceramic / high-strength iron-based composite ingot and a method for manufacturing the same

Abstract

This invention provides a low-cost ceramic / high-strength iron-based composite ingot mold and its preparation method. It employs an integrated molding scheme involving in-situ casting of a high-strength gray cast iron matrix and a three-dimensional mesh interlocking ceramic composite preform. The designed preform features T-shaped mesh ribs and conical through holes, which are completely filled by high-temperature molten iron during casting. After solidification, a three-dimensional physically interlocking structure is formed. Simultaneously, the molten iron undergoes an interfacial fusion reaction with the carbon steel reinforcing mesh embedded within the preform, forming a metallurgical bond. This completely solves the industry problem of edge warping and detachment in flat preforms. This invention places ceramic reinforcement only in critical areas such as the high-loss mold bottom center, achieving precise localized armor. With minimal increase in material costs, it significantly extends the service life of the ingot mold. It successfully solves a key technical bottleneck in the ferroalloy industry for achieving mechanized and automated continuous production of casting machines, possessing extremely high industrial application value.

Description

Technical Field

[0001] This invention relates to the field of ingot mold technology for ferroalloy casting, and in particular to a low-cost ceramic / high-strength iron-based composite material ingot mold and its preparation method. Background Technology

[0002] Casting molds are crucial equipment in ferroalloy production, particularly in ferrosilicon smelting. In ferrosilicon production, molten ferrosilicon at temperatures reaching 1500-1550℃ is directly poured into the mold, solidifying layer by layer. The working environment of the mold is extremely harsh, frequently subjected to intense erosion from the high-temperature molten iron, rapid heating, and rapid cooling, generating enormous alternating thermal stress. Currently, the commonly used mold materials in the domestic ferroalloy industry are heat-resistant gray cast iron, heat-resistant vermicular graphite cast iron, or heat-resistant ductile iron. Since the melting point of cast iron is typically only 1160-1200℃, lower than the casting temperature of molten ferrosilicon, the working surface of the mold is continuously subjected to the erosion and scouring of high-temperature molten iron during service, resulting in a typical single-sided service life of only 25 to 60 days. Taking the actual production data of Erdos Group Electrometallurgical Company as an example, the service life of a single side of a common ingot mold is about 25 days for the first mold and about 60 days for the intermediate mold. The cost of the ingot mold accounts for 13.32% of the total material cost. Frequent shutdowns to replace ingot molds seriously affect the efficiency of continuous production of ferroalloys, increase the safety risks of operators, and have become a key technical bottleneck restricting the realization of mechanized and automated casting in the ferroalloy industry.

[0003] To extend the life of ingot molds, the industry has mainly conducted research in two directions. On the one hand, it focuses on optimizing the material of cast iron to improve its thermal fatigue resistance. For example, the original patent CN116657028A (this patent was written by me, but it was rejected; can it be used as a prior art document?) discloses a method for preparing high-strength gray cast iron. Using scrap steel as the main raw material, combined with graphite carburization and secondary inoculation treatment, it eliminates the inherited properties of cast iron, increasing the tensile strength of gray cast iron to over 450 MPa and achieving an elongation of over 2%. Based on this high-strength gray cast iron, the patent also proposes a combined anti-fracture ingot mold structure. The ingot mold is designed as a symmetrical two-part structure, connected by flanges, with high-temperature resistant aluminosilicate fibers placed at the connection points. This aims to release thermal stress through the split structure and prevent transverse fracture. On the other hand, some research attempts to form a ceramic reinforcement layer on the working surface of the ingot mold through V-process casting or inlay casting, utilizing the high melting point and low wettability of ceramics to resist molten iron loss. For example, a flat ceramic preform is fixed in a sand mold cavity using ceramic nails, and then a gray cast iron matrix is ​​cast to form a composite ingot mold.

[0004] However, the aforementioned existing technologies still have insurmountable drawbacks. For the combined ingot mold of CN116657028A, its two-part connection structure not only increases assembly processes and the cost of replacing seals, but also, after long-term use, the high-temperature resistant aluminum silicate fiber sealing material at the flange connection is prone to aging and loss of elasticity under repeated hot and cold cycles, leading to leakage of molten ferrosilicon from the gaps. This can cause the ingot molds to become "cast-locked" or stuck on the casting machine, creating a new failure mode. For the flat-plate ceramic preform composite scheme using ceramic nails for fixing, the interface is a simple planar mechanical connection. Under frequent thermal cycling conditions of large-size ingot molds, due to the significant difference in deformation compatibility between the high-strength gray cast iron matrix and the ceramic preform, thermal stress is highly concentrated at the edges of the preform and near the ceramic nail fixing points, easily causing edge warping, local cracking, or even complete detachment of the preform. Especially at the feed end where molten ferrosilicon directly impacts, melting loss and detachment problems are more prominent. Furthermore, the positioning accuracy of the ceramic nail fixing process is poor, and the impact force of the high-temperature molten iron during casting easily causes displacement of the preform, resulting in low yield. Therefore, there is an urgent need in this field to develop a novel ingot mold and its low-cost, high-reliability preparation method that can utilize the excellent plasticity and toughness of high-strength gray cast iron to resist thermal fatigue fracture, provide long-term reinforcement to localized erosion areas, and possess superior interfacial bonding capabilities to avoid the risks of leakage in the composite structure and preform detachment. Summary of the Invention

[0005] The purpose of this invention is to provide a low-cost ceramic / high-strength iron-based composite material ingot mold and its preparation method, so as to solve the problems existing in the prior art.

[0006] To achieve the above objectives, the present invention provides the following solution: This invention provides a low-cost ceramic / high-strength iron-based composite ingot mold, comprising an ingot mold matrix and at least a local composite reinforcement disposed at the ingot mold feed end and the center of the mold bottom; The ingot mold base is made of high-strength gray cast iron with a tensile strength ≥450MPa and an elongation ≥2%; the local composite reinforcement is a three-dimensional mesh interlocking ceramic composite preform, which is composited with the ingot mold base by in-situ casting. The three-dimensional mesh interlocking ceramic composite prefabricated body includes a working panel and multiple T-shaped mesh ribs integrally formed on the lower surface of the working panel. The T-shaped mesh ribs are distributed in a mesh pattern, and multiple tapered through holes with smaller upper parts and larger lower parts are spaced apart on the ribs. In addition, carbon steel reinforcing mesh is pre-embedded inside the prefabricated body along the direction of the T-shaped mesh ribs.

[0007] Preferably, the T-shaped mesh ribs have a mesh spacing of 50-80mm, a rib body width of 8-12mm, a T-shaped flange width of 16-24mm, and a rib height of 1 / 2 to 2 / 3 of the working panel thickness; the working panel thickness is 20-35mm.

[0008] Preferably, the taper of the conical through hole is 1:5 to 1:10, the diameter of the small hole is 3-4 mm, the diameter of the large hole is 6-8 mm, and the interval between adjacent conical through holes is 40-60 mm.

[0009] Preferably, the three-dimensional mesh interlocking ceramic composite preform is composed of the following raw materials by weight: 40-50 parts of bauxite clinker, 20-30 parts of quartz powder, 10-15 parts of silicon carbide fine powder, 0.5-1.5 parts of chopped carbon fiber, and 15-20 parts of aluminum sol binder.

[0010] Preferably, the diameter of the carbon steel reinforcing mesh is 4-6 mm; the chemical composition of the high-strength gray cast iron by weight percentage is: C 3.0-3.2%, Si 1.6-1.8%, Mn 0.8-1.0%, Cr 0.3-0.4%, Cu 0.6-0.7%, with the balance being Fe.

[0011] This invention also provides a method for preparing a low-cost ceramic / high-strength iron-based composite ingot mold, comprising the following steps: Step 1: Preparation of three-dimensional mesh interlocking ceramic composite preform: After mixing the ceramic raw materials, a preform blank with T-shaped mesh ribs and conical through holes is manufactured using a molding process. During the molding process, carbon steel mesh is pre-embedded inside the T-shaped ribs. After drying and sintering, the preform is obtained. Step 2, Sand mold making and preform positioning: Make a sand mold according to the shape of the ingot mold, set positioning grooves at the corresponding positions of the sand mold, and fix the sintered preform by directly embedding it into the positioning grooves through its T-shaped grid ribs; Step 3, High-strength gray cast iron smelting and casting: The furnace charge is prepared according to the composition of high-strength gray cast iron. After smelting, composition adjustment and secondary inoculation treatment, the resulting molten iron is cast into the sand mold in which the precast body has been placed. The molten iron fills the grid cavity and conical through hole of the precast body and forms a metallurgical bond with the carbon steel mesh. Step 4, Cooling and Cleaning: After the casting has cooled, it is opened and cleaned to obtain the composite material ingot mold.

[0012] Preferably, in step one, the molding process adopts 3D printing extrusion molding or vibration pressure molding; the drying temperature is 80-120℃, the drying time is 24-48 hours; the sintering temperature is 1100-1250℃, the sintering time is 2-4 hours, and the sintering atmosphere is an oxidizing atmosphere or a weak reducing atmosphere.

[0013] Preferably, in step three, the furnace charge comprises, by mass percentage: 50-60% scrap steel, 30-40% pig iron, 2.6% ferrosilicon, 1.2% ferromanganese, 0.6% ferrochrome, and 1.5-2.0% carbon raiser; after smelting, the furnace charge is heated to 1450-1480℃ and then tapped out; the secondary inoculation treatment includes: adding 0.4-0.6% of a barium silicon inoculant by mass of the molten iron during tapping for primary inoculation, and adding 0.1-0.3% of a barium silicon inoculant by mass of the molten iron during casting for secondary inoculation.

[0014] Preferably, in step three, the casting temperature is 1350-1400℃.

[0015] Preferably, in step two, the working surface of the preform is flush with or 0-2 mm below the surface of the sand mold cavity.

[0016] The present invention achieves the following beneficial technical effects compared to the prior art: This invention provides a low-cost ceramic / high-strength iron-based composite ingot mold and its preparation method. It abandons the flange connection structure of the combined ingot mold in the original patent, adopting an integrated molding scheme of in-situ casting of a high-strength gray cast iron matrix and a three-dimensional mesh interlocking ceramic composite preform. This structurally eliminates the risks of molten iron leakage and loosening of assembled components. Crucially, the preform designed in this invention features T-shaped mesh ribs and conical through holes, which are completely filled with high-temperature molten iron during casting. After solidification, a three-dimensional physical interlocking structure, like tree roots embedded in soil, is formed. Simultaneously, the molten iron undergoes an interfacial fusion reaction with the carbon steel reinforcing mesh embedded inside the preform, forming a metallurgical bond. This dual reinforcement mechanism increases the interfacial shear strength by over 100%, completely solving the industry problem of edge warping and detachment in flat preforms. This invention only sets ceramic reinforcements in key areas such as the high-loss feed end and the center of the mold bottom, achieving precise localized armor. With minimal increase in material costs, it significantly extends the service life of the ingot mold. Actual user reports indicate that the ceramic composite ingot molds prepared using the technical solution of this invention have a service life exceeding 193 days and are in good condition, with an estimated lifespan of over 210 days. This is more than 2.5 times longer than the 60-day service life of ordinary heat-resistant cast iron ingot molds, and more than 1.5 times longer than the combined high-strength gray cast iron ingot molds of the original patent. The cost per ton of iron accounted for by the ingot mold has decreased from RMB 15.44 / ton for ordinary ingot molds to below RMB 4.10 / ton, a reduction of over 70%. Furthermore, by eliminating complex flange assembly and sealing processes and preventing leakage accidents, production safety and operational efficiency have been significantly improved. This invention successfully solves the key technical bottleneck in achieving mechanized and automated continuous production in the ferroalloy industry, and has extremely high industrial application value. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the low-cost ceramic / high-strength iron-based composite ingot mold structure provided by the present invention; Figure 2 A flowchart illustrating the preparation method of the low-cost ceramic / high-strength iron-based composite ingot mold provided by this invention. Detailed Implementation

[0019] Unless otherwise specified, the terms "connection" and "linkage" used in this application include both direct and indirect connections (linkages). In the description of this invention, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention.

[0020] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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.

[0022] The purpose of this invention is to provide a low-cost ceramic / high-strength iron-based composite material ingot mold and its preparation method, so as to solve the problems existing in the prior art.

[0023] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] Example 1 This embodiment provides a low-cost ceramic high-strength iron-based composite material ingot mold, which is a silicon-iron casting machine mold with a length of 1.7 meters and a width of 1.5 meters.

[0025] The ingot mold base in this embodiment is made of high-strength gray cast iron. The chemical composition of this high-strength gray cast iron by weight percentage is: C 3.1%, Si 1.7%, Mn 0.9%, Cr 0.35%, Cu 0.65%, with the balance being Fe.

[0026] In this embodiment, a local composite reinforcement is disposed in the feed end region of the ingot mold. This reinforcement is a three-dimensional mesh interlocking ceramic composite preform. The working panel 1 of the preform is 30mm thick. T-shaped mesh ribs 2 are integrally formed on the lower surface of the working panel 1. The ribs are distributed in a grid pattern with a mesh spacing of 60mm. The main body width of the rib is 10mm, the width of the T-shaped flange is 20mm, and the rib height is 15mm. On each T-shaped mesh rib, a tapered through hole 3 is provided every 50mm. The taper of this hole is 1:8, the small hole diameter is 3.5mm, and the large hole diameter is 7mm. A 5mm diameter carbon steel reinforcing mesh is pre-embedded inside the preform along the rib direction.

[0027] The preform is made from the following raw materials by weight: 45 parts bauxite clinker, 25 parts quartz powder, 12 parts silicon carbide fine powder, 1 part chopped carbon fiber, and 18 parts aluminum sol binder.

[0028] The preparation method is as follows: First, mix the above dry materials for 8 minutes, then add aluminum sol and water, and mix until a dough forms that does not crumble when kneaded. Using a 3D printing extrusion molding process, a preform blank with T-shaped mesh ribs and conical through holes is manufactured. During the molding process, the bent carbon steel mesh is accurately embedded into the T-shaped ribs. The blank is then dried at 100℃ for 36 hours, and then sintered at 1200℃ in a weak reducing atmosphere for 3 hours to obtain the preform.

[0029] Secondly, a sand mold is made according to the shape of the ingot mold, and a positioning groove matching the T-shaped ribs of the preform is set at the corresponding position of the sand mold feed end. The sintered preform is directly embedded into the positioning groove through its T-shaped grid ribs, and the working surface of the preform is flush with the surface of the sand mold cavity.

[0030] Then, the furnace charge was prepared according to the composition of high-strength gray cast iron, comprising the following percentages by mass: 55% scrap steel, 35% pig iron, 2.6% ferrosilicon, 1.2% ferromanganese, 0.6% ferrochrome, and 1.8% carbon raiser. The charge was placed in a medium-frequency induction furnace and heated to melt. A rapid pre-furnace analyzer was used to adjust the composition to the acceptable range, and the furnace was tapped at 1460℃. A two-stage inoculation process was employed: 0.5% (5mm particle size) of barium silicon inoculant was added during tapping for primary inoculation, and 0.2% (5mm particle size) of barium silicon inoculant was added during casting for secondary inoculation. At a casting temperature of 1380℃, the molten iron was smoothly poured into a sand mold containing the precast body.

[0031] Finally, after the casting has cooled naturally in the sand mold to below 500°C, the mold is opened, the risers and gating system are cleaned, and the flash is removed to obtain the composite material ingot mold of this embodiment.

[0032] Example 2 This embodiment is basically the same as Embodiment 1, except that: the T-shaped grid rib spacing of the preform is 50mm, the rib body width is 8mm, the T-shaped flange width is 16mm, and the rib height is 18mm (working panel thickness 30mm). The tapered through holes are spaced 40mm apart, with a taper of 1:5, a small hole diameter of 3mm, and a large hole diameter of 6mm. The preform is made from the following raw materials by weight: 40 parts bauxite clinker, 30 parts quartz powder, 10 parts silicon carbide fine powder, 0.5 parts chopped carbon fiber, and 15 parts alumina sol binder. The sintering temperature is 1100℃, and the sintering time is 4 hours. The composition of the high-strength gray cast iron is adjusted to: C 3.0%, Si 1.6%, Mn 0.8%, Cr 0.3%, Cu 0.6%. Other preparation parameters are the same as in Embodiment 1.

[0033] Example 3 This embodiment is basically the same as Embodiment 1, except that: the T-shaped grid rib spacing of the preform is 80mm, the rib body width is 12mm, the T-shaped flange width is 24mm, and the rib height is 12mm (working panel thickness 20mm). The tapered through holes are spaced 60mm apart, with a taper of 1:10, a small hole diameter of 4mm, and a large hole diameter of 8mm. The preform is made from the following raw materials by weight: 50 parts bauxite clinker, 20 parts quartz powder, 15 parts silicon carbide fine powder, 1.5 parts chopped carbon fiber, and 20 parts alumina sol binder. The sintering temperature is 1250℃, and the sintering time is 2 hours. The composition of the high-strength gray cast iron is adjusted to: C 3.2%, Si 1.8%, Mn 1.0%, Cr 0.4%, Cu 0.7%. Other preparation parameters are the same as in Embodiment 1.

[0034] Comparative Example 1 This comparative example uses the high-strength gray cast iron integral ingot mold prepared in the original patent CN116657028A example. No ceramic composite reinforcement is set. The ingot mold is an integral structure and the material composition is the same as that of Example 1.

[0035] Comparative Example 2 This comparative example uses a composite scheme of a flat ceramic preform and high-strength gray cast iron. The preform is a flat plate structure without any ribs or through holes, with a thickness of 30 mm, and the material is the same as in Example 1. The preform is fixed to the feed end of the sand mold cavity using a traditional ceramic nail fixing method with four ceramic nails. Then, high-strength gray cast iron with the same composition as in Example 1 is cast to obtain a composite material ingot mold.

[0036] Comparative Example 3 This comparative example uses a commercially available ordinary heat-resistant gray cast iron ingot mold, whose chemical composition by weight percentage is: C 3.2%, Si 1.9%, Mn 0.6%, Cr 0.2%, with the balance being Fe, without any inoculation treatment.

[0037] Performance testing and effect evaluation The ingot molds (medium-sized ingot molds, all 1.7m × 1.5m) prepared in Examples 1-3 and Comparative Examples 1-3 were subjected to simulated service tests under the same industrial field conditions. The test conditions were: molten ferrosilicon at a casting temperature of 1500-1550℃, casting every 4 hours, naturally cooling to room temperature, and cycling 6 times per day. The evaluation indicators included: interfacial shear strength (for composite materials, the push-pull method was used), number of cycles before the first transverse crack appeared, average erosion depth at the feed end (after 200 cycles), and final service life (days, with failure defined as penetrating transverse fracture or erosion depth at the feed end exceeding 20mm). The test results are shown in Table 1.

[0038] Table 1. Performance test results of ingot molds in the examples and comparative examples

[0039] As can be seen from the test results in Table 1, the composite material ingot molds prepared in Examples 1-3 of this invention exhibit an interfacial shear strength of over 45 MPa between the preform and the matrix, far exceeding the planar bonding strength of Comparative Example 2. This indicates that the dual mechanism of the three-dimensional interlocking structure and metallurgical bonding plays a decisive reinforcing role. Regarding thermal fatigue resistance, Examples 1-3 showed no transverse cracks after 500 thermal cycles, while the high-strength gray cast iron integral ingot mold of Comparative Example 1 cracked after 85 cycles, and the ordinary ingot mold of Comparative Example 3 cracked after only 45 cycles. This proves that the composite material structure of this invention effectively releases thermal stress and protects the high-strength gray cast iron matrix. In terms of erosion resistance, the erosion depth of Examples 1-3 after 200 cycles was only 3.2-3.8 mm, far superior to the 18.5 mm of Comparative Example 1 and the 22.3 mm of Comparative Example 3, demonstrating the excellent resistance of the ceramic preform to molten iron erosion and melting. Ultimately, the ingot mold of Example 1 achieved a service life of 215 days, a 176% improvement over 78 days in Comparative Example 1, a 63% improvement over 132 days in Comparative Example 2, and a significant 291% improvement over 55 days in Comparative Example 3. Furthermore, while the ingot mold of Comparative Example 2 initially performed better than the integral cast iron ingot mold, after 150 cycles, due to concentrated interfacial thermal stress, the edges of the flat preform showed significant warping, leading to molten iron seeping into the bonding interface and accelerating localized detachment and failure. In contrast, the ingot mold of the present invention maintained an intact interface throughout the entire testing cycle, with no warping or detachment observed. User reports and test records also confirmed that the ceramic ingot mold using the technical concept of this invention has operated safely for 193 days in good condition during intermediate mold applications, reducing the cost per ton of iron from RMB 15.44 / ton to RMB 4.10 / ton, achieving significant economic benefits and technological progress.

[0040] In summary, this invention, through its ingenious three-dimensional interlocking mesh structure design and in-situ casting composite process, fundamentally solves the technical problems of transverse fracture, interface failure, and localized melting in existing technologies with extremely low cost increments. It possesses significant creativity, practicality, and industrial application prospects.

[0041] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0042] It should be noted that the components mentioned in the above embodiments are all general standard parts or components known to those skilled in the art. Their structures and principles can be learned by those skilled in the art through technical manuals or conventional experimental methods.

[0043] This invention has illustrated its principles and implementation methods using specific examples. The descriptions of these embodiments are merely illustrative of the method and its core ideas; furthermore, those skilled in the art will recognize that modifications may be made to the specific implementation methods and application scope based on the principles of this invention. Therefore, the content of this specification should not be construed as limiting the invention.

Claims

1. A low-cost ceramic / high-strength iron-based composite ingot mold, characterized in that, Includes a mold base and at least a local composite reinforcement disposed at the mold feed end and the center of the mold bottom; The ingot mold base is made of high-strength gray cast iron with a tensile strength ≥450MPa and an elongation ≥2%; the local composite reinforcement is a three-dimensional mesh interlocking ceramic composite preform, which is composited with the ingot mold base by in-situ casting. The three-dimensional mesh interlocking ceramic composite prefabricated body includes a working panel and multiple T-shaped mesh ribs integrally formed on the lower surface of the working panel. The T-shaped mesh ribs are distributed in a mesh pattern, and multiple tapered through holes with smaller upper parts and larger lower parts are spaced apart on the ribs. In addition, carbon steel reinforcing mesh is pre-embedded inside the prefabricated body along the direction of the T-shaped mesh ribs.

2. The low-cost ceramic / high-strength iron-based composite material ingot mold according to claim 1, characterized in that, The T-shaped mesh ribs have a mesh spacing of 50-80mm, a rib body width of 8-12mm, a T-shaped flange width of 16-24mm, and a rib height of 1 / 2 to 2 / 3 of the working panel thickness; the working panel thickness is 20-35mm.

3. The low-cost ceramic / high-strength iron-based composite material ingot mold according to claim 1, characterized in that, The taper of the conical through hole is 1:5 to 1:10, the diameter of the small hole is 3-4 mm, the diameter of the large hole is 6-8 mm, and the interval between adjacent conical through holes is 40-60 mm.

4. The low-cost ceramic / high-strength iron-based composite ingot mold according to claim 1, characterized in that, The three-dimensional mesh interlocking ceramic composite preform is composed of the following raw materials by weight: 40-50 parts of bauxite clinker, 20-30 parts of quartz powder, 10-15 parts of silicon carbide fine powder, 0.5-1.5 parts of short-cut carbon fiber, and 15-20 parts of aluminum sol binder.

5. The low-cost ceramic / high-strength iron-based composite ingot mold according to claim 1, characterized in that, The diameter of the carbon steel reinforcing mesh is 4-6 mm; the chemical composition of the high-strength gray cast iron by weight percentage is: C 3.0-3.2%, Si 1.6-1.8%, Mn 0.8-1.0%, Cr 0.3-0.4%, Cu 0.6-0.7%, with the balance being Fe.

6. A method for preparing a low-cost ceramic / high-strength iron-based composite ingot mold according to any one of claims 1 to 5, characterized in that, Includes the following steps: Step 1: Preparation of three-dimensional mesh interlocking ceramic composite preform: After mixing the ceramic raw materials, a preform blank with T-shaped mesh ribs and conical through holes is manufactured using a molding process. During the molding process, carbon steel mesh is pre-embedded inside the T-shaped ribs. After drying and sintering, the preform is obtained. Step 2, Sand mold making and preform positioning: Make a sand mold according to the shape of the ingot mold, set positioning grooves at the corresponding positions of the sand mold, and fix the sintered preform by directly embedding it into the positioning grooves through its T-shaped grid ribs; Step 3, High-strength gray cast iron smelting and casting: The furnace charge is prepared according to the composition of high-strength gray cast iron. After smelting, composition adjustment and secondary inoculation treatment, the resulting molten iron is cast into the sand mold in which the precast body has been placed. The molten iron fills the grid cavity and conical through hole of the precast body and forms a metallurgical bond with the carbon steel mesh. Step 4, Cooling and Cleaning: After the casting has cooled, it is opened and cleaned to obtain the composite material ingot mold.

7. The preparation method according to claim 6, characterized in that, In step one, the molding process adopts 3D printing extrusion molding or vibration pressure molding; the drying temperature is 80-120℃, and the drying time is 24-48 hours; the sintering temperature is 1100-1250℃, the sintering time is 2-4 hours, and the sintering atmosphere is an oxidizing atmosphere or a weak reducing atmosphere.

8. The preparation method according to claim 6, characterized in that, In step three, the furnace charge comprises, by mass percentage: 50-60% scrap steel, 30-40% pig iron, 2.6% ferrosilicon, 1.2% ferromanganese, 0.6% ferrochrome, and 1.5-2.0% carbon raiser; after smelting, the furnace charge is heated to 1450-1480℃ and then tapped out; the secondary inoculation treatment includes: adding 0.4-0.6% of a silicon-barium inoculant by mass of the molten iron during tapping for primary inoculation, and adding 0.1-0.3% of a silicon-barium inoculant by mass of the molten iron during casting for secondary inoculation.

9. The preparation method according to claim 6, characterized in that, In step three, the casting temperature is 1350-1400℃.

10. The preparation method according to claim 6, characterized in that, In step two, the working surface of the preform is flush with or 0-2mm lower than the surface of the sand mold cavity.

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