High-damping ceramic-based machine tool moving part and preparation method thereof

Abstract

This invention discloses a high-damping ceramic-based machine tool moving part and its preparation method, which is made from raw materials comprising the following components: First sintering raw materials: silicon dioxide, alumina, calcium oxide, magnesium oxide, ferric oxide, titanium dioxide, potassium oxide, and sodium oxide; first sintering aids including borax, calcium fluoride, pore-reducing agent, and surfactant; second sintering additives including glass powder and supplementary aids, including borax, calcium fluoride, pore-reducing agent, and surfactant, with the amount of each supplementary aid being 1 / 3 to 1 / 2 of the corresponding aid used in the first sintering. This invention successfully prepares a high-density, high-strength, low-water-absorption, high-damping, and low-thermal-expansion ceramic-based machine tool moving part through a synergistic process of first sintering raw materials (aluminosilicate system), glass powder, three aids (sintering aid, pore-reducing agent, and surfactant), crushing, and secondary vacuum sintering.

Description

Technical Field

[0001] This invention relates to the field of mineral processing machine tool technology, specifically to a high-damping ceramic-based machine tool moving part and its preparation method. Background Technology

[0002] Machine tool moving parts (such as worktables, slides, crossbeams, spindle boxes, tool holders, etc.) are key functional components of CNC machine tools, and they need to withstand dynamic cutting forces, vibration impacts, and temperature changes during high-speed movement. The dynamic characteristics of the moving parts directly determine the machining accuracy, surface quality, and stability of the machine tool. Ceramic materials have advantages such as high hardness, high wear resistance, low thermal expansion, and good chemical stability, making them ideal candidate materials for manufacturing machine tool moving parts. However, traditional ceramic sintering processes cannot avoid residual porosity, with porosity typically reaching 8-12%, resulting in low flexural strength (only 30-40 MPa), insufficient density, and significant sintering deformation and cracking problems in large-sized, complex-shaped products, severely limiting their application in the field of machine tool moving parts. Existing technologies have proposed methods such as hot pressing sintering, vacuum sintering, and adding sintering aids to reduce porosity, but single measures often have limited effectiveness and are costly. Especially for large moving parts, even if hot pressing and sintering are used, the internal gas discharge channels are not smooth and there will still be closed pores, making it difficult to meet the stringent requirements of high-end machine tools for moving parts to be highly dense, high-strength, high-damping, and low thermal expansion. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides a high-damping ceramic-based machine tool moving part and its preparation method. Through a synergistic process of first sintering raw materials (aluminosilicate system) combined with glass powder, three additives (sintering aid, pore-reducing agent, and surfactant), second vacuum sintering, and crushing, a ceramic-based machine tool moving part with high density, high strength, low water absorption, high damping, and low thermal expansion is successfully prepared.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a high-damping ceramic-based machine tool moving part, made from raw materials comprising the following components: Raw materials for the first sintering: 52.5-53.5 parts silicon dioxide, 16.2-16.8 parts aluminum oxide, 7.8-8.2 parts calcium oxide, 4.8-5.2 parts magnesium oxide, 7.8-8.2 parts ferric oxide, 0.6-1.0 parts titanium dioxide, 2.1-2.5 parts potassium oxide, and 3.6-4.0 parts sodium oxide; And the first sintering aid, including: Borax, used at a rate of 1.5-2% of the total mass of the raw materials for the first sintering. Calcium fluoride, used at a rate of 1-2% of the total mass of the raw materials for the first sintering. The pore-reducing agent is selected from starch or ammonium bicarbonate. The amount of starch used is 0.5-1% of the total mass of the raw materials for the first sintering, and the amount of ammonium bicarbonate used is 1-3% of the total mass of the raw materials for the first sintering. The surfactant, zinc stearate, is used at a rate of 0.15-0.25% of the total mass of the raw materials used in the first sintering. Second sintering additives: The amount of glass powder used is 4-6% of the total mass of the crushed particles after the first sintering. The softening point of the glass powder is 700-800℃. In addition, supplementary additives, including borax, calcium fluoride, pore-reducing agent and surfactant, are added, with the amount of each supplementary additive being 1 / 3 to 1 / 2 of the amount of the corresponding additive used in the first sintering.

[0005] Furthermore, after the first sintering, the sintered body is broken down to a particle size of 10-20 mm, and then a second sintering is performed.

[0006] Furthermore, the second sintering is vacuum sintering, with the vacuum level controlled at no less than 10. -3 Pa, temperature 1050-1150℃, heat preservation time 2-3 hours.

[0007] Furthermore, the first sintering adopts a gradient heating process, including: from room temperature to 300°C, heating rate of 3-8°C / min; from 300 to 800°C, heating rate of 2-5°C / min; from 800 to 1250°C, heating rate of 1-3°C / min; and sintering at 1250°C for 2-3 hours; followed by forced air cooling after furnace cooling to 800°C.

[0008] Furthermore, the raw materials are pretreated before the first sintering, including: drying to a moisture content of ≤0.3% at a temperature of 120-150℃ for 30-45 minutes; magnetic separation to remove iron to an iron content of <0.5%; and acid washing to decarburize to remove organic matter residue of <0.1%.

[0009] Furthermore, the ceramic-based machine tool moving parts are worktables, slides, crossbeams, spindle boxes, or tool holders.

[0010] On the other hand, the method for preparing the high-damping ceramic-based machine tool moving part includes the following steps: S1: Weigh the raw materials and additives for the first sintering according to the proportion, mix them evenly to obtain the mixture; S2: Compact the mixture and expel the gas; S3: The compacted mixture is sintered for the first time at a temperature of 1100-1250℃ for 2-3 hours. After cooling to 800℃ in the furnace, it is forced to air-cool to obtain the sintered body. S4: The sintered body is crushed to a particle size of 10-20mm to obtain crushed particles; S5: Add a second sintering additive to the crushed particles. The second sintering additive includes glass powder and supplementary additives. The amount of glass powder added is 4-6% of the total mass of the crushed particles. The softening point of the glass powder is 700-800℃. The supplementary additives include borax, calcium fluoride, pore-reducing agent and surfactant. The amount of each supplementary additive is 1 / 3 to 1 / 2 of the amount of the corresponding additive in the first sintering additive. S6: The crushed particles after adding the second sintering additives are subjected to a second vacuum sintering, with a vacuum degree of not less than 10. -3 Pa, sintering temperature is 1050-1150℃, hold for 2-3 hours, and after cooling, the high-damping ceramic-based machine tool moving part is obtained.

[0011] The ceramic-based machine tool moving part of the present invention has the following overall beneficial effects: 1. Through a two-stage sintering process (crushing after the first sintering and adding glass powder during the second vacuum sintering), combined with gradient heating and vacuum conditions, the porosity of the product is reduced from the conventional 8-12% to 2-3%; the bulk density is increased to 2.6-2.8 g / cm³, achieving lightweighting, which is beneficial for enabling rapid machine tool movement and reducing drive energy consumption.

[0012] 2. The flexural strength is increased from 30-40MPa to 50-70MPa (≥45MPa meets the requirements of machine tool moving parts), and the compressive strength, elastic modulus and surface hardness are significantly improved. It can withstand the impact and wear during high-speed movement and has excellent mechanical properties.

[0013] 3. The inherently low coefficient of thermal expansion of ceramic materials (approximately 5-8 × 10⁻⁶). -6 The low water absorption rate (0.5-1.5%) and low K / K ratio ensure that the moving parts maintain geometric accuracy under temperature and humidity changes, guaranteeing the long-term data stability of the machine tool. Detailed Implementation

[0014] 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.

[0015] This invention provides a high-damping ceramic-based machine tool moving part, made from raw materials comprising the following components: Raw materials for the first sintering: 52.5-53.5 parts silicon dioxide, 16.2-16.8 parts aluminum oxide, 7.8-8.2 parts calcium oxide, 4.8-5.2 parts magnesium oxide, 7.8-8.2 parts ferric oxide, 0.6-1.0 parts titanium dioxide, 2.1-2.5 parts potassium oxide, and 3.6-4.0 parts sodium oxide; And the first sintering aid, including: Borax, used at a rate of 1.5-2% of the total mass of the raw materials for the first sintering. Calcium fluoride, used at a rate of 1-2% of the total mass of the raw materials for the first sintering. The pore-reducing agent is selected from starch or ammonium bicarbonate. The amount of starch used is 0.5-1% of the total mass of the raw materials for the first sintering, and the amount of ammonium bicarbonate used is 1-3% of the total mass of the raw materials for the first sintering. The surfactant, zinc stearate, is used at a rate of 0.15-0.25% of the total mass of the raw materials used in the first sintering. Second sintering additives: Glass powder, used at 4-6% of the total mass of the crushed particles after the first sintering, has a softening point of 700-800℃. During the second sintering, the glass powder melts first, forming a liquid phase that fills the voids between the crushed particles, acting as both a flux and a binder, further reducing porosity and improving flexural strength and surface density. The preferred addition amount of glass powder is 5%, which ensures sufficient liquid phase formation while avoiding excessive glass phase that could increase material brittleness.

[0016] In addition, supplementary additives, including borax, calcium fluoride, pore-reducing agent and surfactant, are added, with the amount of each supplementary additive being 1 / 3 to 1 / 2 of the amount of the corresponding additive used in the first sintering.

[0017] In this invention, borax (Na2B4O7·10H2O) and calcium fluoride are used as sintering aids. The amount of borax added is 1.5-2% of the total mass of the raw materials, and the amount of calcium fluoride added is 1-2% of the total mass of the raw materials. Borax and calcium fluoride synergistically reduce the sintering temperature by 100-150℃, promote the formation of the liquid phase, and improve the densification rate. The pore-eliminating agent is starch (particle size <100μm) or ammonium bicarbonate. The amount of starch added is 0.5-1% of the total mass of the raw materials, and the amount of ammonium bicarbonate added is 1-3% of the total mass of the raw materials. The pore-eliminating agent decomposes and releases gas at high temperature. The decomposition of the agent helps to remove the original closed pores and gas inclusions inside the green body. At the same time, the tiny vacancies left after its decomposition can be filled in the subsequent liquid phase sintering, thereby reducing the total porosity. By controlling the type, amount and sintering process of the depore-removing agent, a small amount of uniformly distributed submicron-sized closed pores can be retained to regulate the damping performance of the material while ensuring high density. The surfactant is zinc stearate, which is added at 0.15-0.25% of the total mass of the raw materials. Zinc stearate reduces the surface tension of the melt, reduces bubble retention, and further reduces the porosity.

[0018] The ceramic-based machine tool moving parts of this invention are a ceramic system mainly composed of aluminosilicates: silicon dioxide and alumina form the framework, while fluxes such as calcium oxide, magnesium oxide, and ferric oxide lower the sintering temperature, and potassium oxide and sodium oxide adjust the melt viscosity. After two sintering processes, this formula yields a high-density, low-porosity, high-strength, and high-hardness ceramic material, suitable for machine tool moving parts subjected to dynamic loads and vibrations. Furthermore, the raw materials are widely available and the cost is controllable, making it suitable for industrial production.

[0019] In this invention, the raw materials are mixed evenly, compacted, and degassed before undergoing a first sintering process. This process removes adsorbed gases and reaction-generated gases (such as CO2 and H2O) from the raw materials, reducing porosity. The sintering temperature is 1100-1250℃, which allows the glass phase to fully form and encapsulate the aggregate particles, laying the foundation for subsequent densification.

[0020] In this invention, after the first sintering, the sintered body is broken down to a particle size of 10-20 mm, and then a second sintering is performed. The breaking process destroys the closed pores remaining in the first sintered body, allowing the internal gas to be released; at the same time, the surface of the broken particles becomes a new active interface, which makes it easier to achieve densification through particle rearrangement and liquid phase flow in the second sintering, significantly reducing the porosity of the final product and improving the bulk density and mechanical properties.

[0021] In this invention, the second sintering is vacuum sintering, with the vacuum level controlled at no less than 10. -3 Pa, temperature 1050-1150℃, holding time 2-3 hours, not less than 10 -3 The high vacuum conditions of Pa greatly promote the discharge of residual gas in the interparticle gaps and prevent the gas from being trapped in the melt; the temperature range of 1050-1150℃ is slightly lower than the first sintering temperature to avoid excessive grain growth, while ensuring that the glass powder is fully melted and wetted to the particle interface, thereby increasing the material densification rate, reducing the porosity, and thus improving the flexural strength.

[0022] In this invention, the first sintering employs a gradient heating process. This gradient heating avoids excessively rapid heating that could lead to concentrated gas release and the formation of large air pockets. The process includes: From room temperature to 300℃, heating rate 3-8℃ / min; thoroughly remove adsorbed water; 300-800℃, heating rate 2-5℃ / min; decomposes carbonates and organic matter; 800-1250℃, heating rate 1-3℃ / min; promotes glass phase formation; The material is sintered at 1250℃ and held for 2-3 hours to ensure sufficient liquid phase flow and pore closure. Afterward, it is cooled in the furnace to 800℃ and then subjected to forced air cooling to reduce microcracks caused by later crystallization. The combined effect reduces the porosity from 8-12% to 2-4% and increases the bulk density from 2.3-2.5 g / cm³ to 2.6-2.8 g / cm³.

[0023] In this invention, the raw materials undergo pretreatment before the first sintering, including: drying to a moisture content ≤0.3% to prevent water vaporization and the formation of pores, at a drying temperature of 120-150℃ for 30-45 minutes; magnetic separation to remove iron to an iron content <0.5% to reduce the release of oxygen from the reduction of iron oxide at high temperatures; and acid washing to decarburize to ensure organic matter residue <0.1% and prevent gas generation from pyrolysis. These pretreatment measures control the chemical and physical factors of pore formation from the source, ensuring the purity of the raw materials and the stability of sintering.

[0024] In this invention, the ceramic-based machine tool moving parts are worktables, slides, crossbeams, spindle boxes, or tool holders. These components bear loads and vibrations during machine tool operation. When made of the high-density, high-strength ceramic material of this invention, they have advantages such as high specific stiffness, good thermal stability, wear resistance, and corrosion resistance, which can significantly improve the dynamic performance and machining accuracy of the machine tool while reducing maintenance costs.

[0025] In this invention, the method for preparing the high-damping ceramic-based machine tool moving part includes the following steps: S1: Weigh the raw materials and additives for the first sintering according to the proportion, mix them evenly to obtain the mixture; S2: Compact the mixture and expel the gas; S3: The compacted mixture is sintered for the first time at a temperature of 1100-1250℃ for 2-3 hours. After cooling to 800℃ in the furnace, it is forced to air-cool to obtain the sintered body. S4: The sintered body is crushed to a particle size of 10-20mm to obtain crushed particles; S5: Add a second sintering additive to the crushed particles. The second sintering additive includes glass powder and supplementary additives. The amount of glass powder added is 4-6% of the total mass of the crushed particles. The softening point of the glass powder is 700-800℃. The supplementary additives include borax, calcium fluoride, pore-reducing agent and surfactant. The amount of each supplementary additive is 1 / 3 to 1 / 2 of the amount of the corresponding additive in the first sintering additive. S6: The crushed particles after adding the second sintering additives are subjected to a second vacuum sintering, with a vacuum degree of not less than 10. -3 Pa, sintering temperature is 1050-1150℃, hold for 2-3 hours, and after cooling, the high-damping ceramic-based machine tool moving part is obtained.

[0026] The preparation method of this invention effectively solves the problem of complete elimination of pores in traditional ceramic sintering through mixing, compaction, first sintering, crushing, and second sintering processes. By first forming and sintering, and then crushing and re-firing, closed pores are transformed into open pores and re-densified. The process is simple and highly controllable, and is suitable for preparing large-size, complex-shaped ceramic-based machine tool moving parts. The product has a porosity of ≤4% and a flexural strength of ≥50MPa, meeting the requirements of high-end machine tools.

[0027] The beneficial technical effects of the high-damping ceramic-based machine tool moving parts (moving beams) of the present invention will be explained below through several embodiments and comparative examples. Example 1

[0028] This example provides a high-damping ceramic-based machine tool moving part, the preparation method of which includes the following steps: S1: Weigh the raw materials for the first sintering (53 parts silicon dioxide, 16.5 parts aluminum oxide, 8 parts calcium oxide, 5 parts magnesium oxide, 8 parts ferric oxide, 0.8 parts titanium dioxide, 2.3 parts potassium oxide, and 3.8 parts sodium oxide) and the additives for the first sintering according to the proportions: borax (1.8% of the total mass of the raw materials for the first sintering), calcium fluoride (1.5% of the total mass of the raw materials for the first sintering), starch (0.8% of the total mass of the raw materials for the first sintering), and zinc stearate (0.2% of the total mass of the raw materials for the first sintering). Mix them evenly, dry them (fluidized bed dryer, 140℃ / 40min, control the moisture content ≤0.3%), remove iron by magnetic separation, and decarburize by acid washing to obtain the mixture. S2: Compact the mixture (20MPa) and expel the gas; S3: The compacted mixture is sintered for the first time at a temperature of 1250℃ for 2.5 hours. After cooling to 800℃ in the furnace, it is then forced to air-cool to obtain the sintered body. S4: The sintered body is crushed to a particle size of 10-20mm to obtain crushed particles; S5: Add a second sintering additive to the crushed particles. The second sintering additive includes glass powder (5.0% of the total mass of the crushed particles, softening point 700℃), borax (addition amount is 50% of the amount of borax used in the first sintering), calcium fluoride (addition amount is 50% of the amount of calcium fluoride used in the first sintering), starch (addition amount is 50% of the amount of starch used in the first sintering), and zinc stearate (addition amount is 50% of the amount of zinc stearate used in the first sintering), and mix evenly.

[0029] S6: The crushed particles after adding the second sintering additives are subjected to a second vacuum sintering, with a vacuum degree of not less than 10. -3Pa, sintering temperature is 1150℃, holding time is 2.5 hours, and after cooling, the finished product of the high-damping ceramic-based machine tool moving part is obtained. Example 2

[0030] This example provides a high-damping ceramic-based machine tool moving part, the preparation method of which includes the following steps: S1: Weigh the raw materials for the first sintering (53 parts silicon dioxide, 16.5 parts aluminum oxide, 8 parts calcium oxide, 5 parts magnesium oxide, 8 parts ferric oxide, 0.8 parts titanium dioxide, 2.3 parts potassium oxide, and 3.8 parts sodium oxide) and the additives for the first sintering according to the proportions: borax (2.0% of the total mass of the raw materials for the first sintering), calcium fluoride (2.0% of the total mass of the raw materials for the first sintering), ammonium bicarbonate (2.0% of the total mass of the raw materials for the first sintering), and zinc stearate (0.2% of the total mass of the raw materials for the first sintering). Mix them evenly, dry them (fluidized bed dryer, 140℃ / 40min, control the moisture content ≤0.3%), remove iron by magnetic separation, and decarburize by acid washing to obtain the mixture. S2: Compact the mixture (20MPa) and expel the gas; S3: The compacted mixture is sintered for the first time at a temperature of 1250℃ for 2.5 hours. After cooling to 800℃ in the furnace, it is then forced to air-cool to obtain the sintered body. S4: The sintered body is crushed to a particle size of 10-20mm to obtain crushed particles; S5: Add a second sintering additive to the crushed particles. The second sintering additive includes glass powder (5.8% of the total mass of the crushed particles, softening point 700℃), borax (addition amount is 50% of the amount of borax used in the first sintering), calcium fluoride (addition amount is 50% of the amount of calcium fluoride used in the first sintering), ammonium bicarbonate (addition amount is 50% of the amount of ammonium bicarbonate used in the first sintering), and zinc stearate (addition amount is 50% of the amount of zinc stearate used in the first sintering), and mix them evenly.

[0031] S6: The crushed particles after adding the second sintering additives are subjected to a second vacuum sintering, with a vacuum degree of not less than 10. -3 Pa, sintering temperature is 1150℃, heat treatment for 3 hours, and cooling to obtain the finished product of the high-damping ceramic-based machine tool moving part. Example 3

[0032] This example provides a high-damping ceramic-based machine tool moving part, the preparation method of which includes the following steps: S1: Weigh the raw materials for the first sintering (53 parts silicon dioxide, 16.5 parts aluminum oxide, 8 parts calcium oxide, 5 parts magnesium oxide, 8 parts ferric oxide, 0.8 parts titanium dioxide, 2.3 parts potassium oxide, and 3.8 parts sodium oxide) and the additives for the first sintering according to the proportions: borax (1.5% of the total mass of the raw materials for the first sintering), calcium fluoride (1.0% of the total mass of the raw materials for the first sintering), starch (0.5% of the total mass of the raw materials for the first sintering), and zinc stearate (0.2% of the total mass of the raw materials for the first sintering). Mix them evenly, dry them (fluidized bed dryer, 140℃ / 40min, control the moisture content ≤0.3%), remove iron by magnetic separation, and decarburize by acid washing to obtain the mixture. S2: Compact the mixture (20MPa) and expel the gas; S3: The compacted mixture is sintered for the first time at a temperature of 1250℃ for 2.5 hours. After cooling to 800℃ in the furnace, it is then forced to air-cool to obtain the sintered body. S4: The sintered body is crushed to a particle size of 10-20mm to obtain crushed particles; S5: Add a second sintering additive to the crushed particles. The second sintering additive includes glass powder (4.0% of the total mass of the crushed particles, softening point 700℃), borax (addition amount is 50% of the amount of borax used in the first sintering), calcium fluoride (addition amount is 50% of the amount of calcium fluoride used in the first sintering), starch (addition amount is 50% of the amount of starch used in the first sintering), and zinc stearate (addition amount is 50% of the amount of zinc stearate used in the first sintering), and mix evenly.

[0033] S6: The crushed particles after adding the second sintering additives are subjected to a second vacuum sintering, with a vacuum degree of not less than 10. -3 Pa, sintering temperature is 1150℃, holding time is 2.5 hours, and after cooling, the finished product of the high-damping ceramic-based machine tool moving part is obtained. Example 4

[0034] This example provides a high-damping ceramic-based machine tool moving part, the preparation method of which includes the following steps: S1: Weigh the raw materials for the first sintering (53 parts silicon dioxide, 16.5 parts aluminum oxide, 8 parts calcium oxide, 5 parts magnesium oxide, 8 parts ferric oxide, 0.8 parts titanium dioxide, 2.3 parts potassium oxide, and 3.8 parts sodium oxide) and the additives for the first sintering according to the proportions: borax (1.8% of the total mass of the raw materials for the first sintering), calcium fluoride (1.5% of the total mass of the raw materials for the first sintering), ammonium bicarbonate (3.0% of the total mass of the raw materials for the first sintering), and zinc stearate (0.2% of the total mass of the raw materials for the first sintering). Mix them evenly, dry them (fluidized bed dryer, 140℃ / 40min, control the moisture content ≤0.3%), remove iron by magnetic separation, and decarburize by acid washing to obtain the mixture. S2: Compact the mixture (20MPa) and expel the gas; S3: The compacted mixture is sintered for the first time at a temperature of 1250℃ for 2.5 hours. After cooling to 800℃ in the furnace, it is then forced to air-cool to obtain the sintered body. S4: The sintered body is crushed to a particle size of 10-20mm to obtain crushed particles; S5: Add a second sintering additive to the crushed particles. The second sintering additive includes glass powder (4.8% of the total mass of the crushed particles, softening point 700℃), borax (addition amount is 50% of the amount of borax used in the first sintering), calcium fluoride (addition amount is 50% of the amount of calcium fluoride used in the first sintering), ammonium bicarbonate (addition amount is 50% of the amount of ammonium bicarbonate used in the first sintering), and zinc stearate (addition amount is 50% of the amount of zinc stearate used in the first sintering), and mix them evenly.

[0035] S6: The crushed particles after adding the second sintering additives are subjected to a second vacuum sintering, with a vacuum degree of not less than 10. -3 Pa, sintering temperature is 1150℃, holding time is 2.5 hours, and after cooling, the finished product of the high-damping ceramic-based machine tool moving part is obtained.

[0036] Comparative Example 1 This example provides a machine tool moving part, comprising 53 parts silicon dioxide, 16.5 parts aluminum oxide, 8 parts calcium oxide, 5 parts magnesium oxide, 8 parts ferric oxide, 0.8 parts titanium dioxide, 2.3 parts potassium oxide, and 3.8 parts sodium oxide. The preparation method of the machine tool moving part includes the following steps: S1: Mix the raw materials evenly, dry (fluidized bed dryer, 140℃ / 40min, control the moisture content ≤0.3%), remove iron by magnetic separation, and decarbonize by acid washing.

[0037] S2: Compaction (20MPa).

[0038] S3: Sintering: Gradient heating, holding at 1250℃ for 2.5h, then forced air cooling after cooling to 800℃ in the furnace to obtain the machine tool moving crossbeam.

[0039] Comparative Example 2 This example provides a machine tool moving part comprising 53 parts silicon dioxide, 16.5 parts aluminum oxide, 8 parts calcium oxide, 5 parts magnesium oxide, 8 parts ferric oxide, 0.8 parts titanium dioxide, 2.3 parts potassium oxide, and 3.8 parts sodium oxide. The preparation method of the machine tool moving part includes the following steps: S1: Mix the raw materials evenly, dry (fluidized bed dryer, 140℃ / 40min, control the moisture content ≤0.3%), remove iron by magnetic separation, and decarbonize by acid washing.

[0040] S2: Compaction (20MPa).

[0041] S3: First sintering: Gradient heating, holding at 1250℃ for 2.5h, then cooling in the furnace to 800℃ and forced air cooling to obtain the sintered body.

[0042] S4: The sintered body is crushed into 10-20mm particles. The crushed particles are mixed evenly with 15 parts of epoxy resin (E-51) and 3 parts of curing agent. The mixture is then compacted and cured at room temperature for 24 hours to obtain the machine tool moving crossbeam.

[0043] Comparative Example 3 This example provides a machine tool moving part, the manufacturing method of which includes the following steps: S1: Mix the raw materials for the first sintering (53 parts silicon dioxide, 16.5 parts aluminum oxide, 8 parts calcium oxide, 5 parts magnesium oxide, 8 parts ferric oxide, 0.8 parts titanium dioxide, 2.3 parts potassium oxide, and 3.8 parts sodium oxide) with the additives for the first sintering: borax (1.8% of the total mass of the raw materials for the first sintering), calcium fluoride (1.5% of the total mass of the raw materials for the first sintering), starch (0.8% of the total mass of the raw materials for the first sintering), and zinc stearate (0.2% of the total mass of the raw materials for the first sintering), and dry them evenly (fluidized bed dryer, 140℃ / 40min, control the moisture content ≤0.3%), remove iron by magnetic separation, and decarburize by acid washing.

[0044] S2: Compaction (20MPa).

[0045] S3: First sintering: Gradient heating, holding at 1250℃ for 2.5h, then cooling in the furnace to 800℃ and forced air cooling to obtain the sintered body.

[0046] S4: The sintered body is broken into 10-20mm particles.

[0047] S5: Second sintering: Vacuum degree 10 -3 Pa, sintered at 1150℃ for 2.5h, cooled, to obtain the machine tool moving crossbeam.

[0048] Comparative Example 4 This example provides a machine tool moving part, the manufacturing method of which includes the following steps: S1: Mix the first sintering raw materials (53 parts silicon dioxide, 16.5 parts aluminum oxide, 8 parts calcium oxide, 5 parts magnesium oxide, 8 parts ferric oxide, 0.8 parts titanium dioxide, 2.3 parts potassium oxide, and 3.8 parts sodium oxide) evenly, dry (fluidized bed dryer, 140℃ / 40min, control moisture content ≤0.3%), remove iron by magnetic separation, and decarburize by acid washing.

[0049] S2: Compaction (20MPa).

[0050] S3: First sintering: Gradient heating, holding at 1250℃ for 2.5h, then cooling in the furnace to 800℃ and forced air cooling to obtain the sintered body.

[0051] S4: Crush the sintered body into 10-20mm particles; add glass powder (5.0% of the total mass of crushed particles, softening point 700℃) and mix evenly.

[0052] S5: Second sintering: Vacuum degree 10 -3 Pa, sintered at 1150℃ for 2.5h, cooled, to obtain the machine tool moving crossbeam.

[0053] Comparative Example 5 This example provides a machine tool moving part, the manufacturing method of which includes the following steps: S1: Mix the first sintering raw materials (53 parts silicon dioxide, 16.5 parts aluminum oxide, 8 parts calcium oxide, 5 parts magnesium oxide, 8 parts ferric oxide, 0.8 parts titanium dioxide, 2.3 parts potassium oxide, and 3.8 parts sodium oxide) with the additives: borax (1.8% of the total mass of the first sintering raw materials) and calcium fluoride (1.5% of the total mass of the first sintering raw materials), dry them evenly (fluidized bed dryer, 140℃ / 40min, control the moisture content ≤0.3%), remove iron by magnetic separation, and decarburize by acid washing.

[0054] S2: Compaction (20MPa).

[0055] S3: First sintering: Gradient heating, holding at 1250℃ for 2.5h, then cooling in the furnace to 800℃ and forced air cooling to obtain the sintered body.

[0056] S4: Crush the sintered body into 10-20mm particles; add glass powder (5.0% of the total mass of crushed particles, softening point 700℃), borax (addition amount is 50% of the amount of borax used in the first sintering), and calcium fluoride (addition amount is 50% of the amount of calcium fluoride used in the first sintering), and mix evenly.

[0057] S5: Second sintering: Vacuum degree 10 -3 Pa, sintered at 1150℃ for 2.5h, cooled, to obtain the machine tool moving crossbeam.

[0058] Comparative Example 6 This example provides a machine tool moving part, the manufacturing method of which includes the following steps: S1: Mix the first sintering raw materials (53 parts silicon dioxide, 16.5 parts aluminum oxide, 8 parts calcium oxide, 5 parts magnesium oxide, 8 parts ferric oxide, 0.8 parts titanium dioxide, 2.3 parts potassium oxide, and 3.8 parts sodium oxide) with starch (0.8% of the total mass of the first sintering raw materials), dry (fluidized bed dryer, 140℃ / 40min, control moisture content ≤0.3%), remove iron by magnetic separation, and decarburize by acid washing.

[0059] S2: Compaction (20MPa).

[0060] S3: First sintering: Gradient heating, holding at 1250℃ for 2.5h, then cooling in the furnace to 800℃ and forced air cooling to obtain the sintered body.

[0061] S4: Crush the sintered body into 10-20mm particles; add glass powder (5.0% of the total mass of crushed particles, softening point 700℃) and starch (the amount added is 50% of the amount of starch used in the first sintering) and mix evenly.

[0062] S5: Second sintering: Vacuum degree 10 -3 Pa, sintered at 1150℃ for 2.5h, cooled, to obtain the machine tool moving crossbeam.

[0063] Comparative Example 7 This example provides a machine tool moving part, the manufacturing method of which includes the following steps: S1: Mix the first sintering raw materials (53 parts silicon dioxide, 16.5 parts aluminum oxide, 8 parts calcium oxide, 5 parts magnesium oxide, 8 parts ferric oxide, 0.8 parts titanium dioxide, 2.3 parts potassium oxide, and 3.8 parts sodium oxide) with zinc stearate (0.2% of the total mass of the first sintering raw materials), dry (fluidized bed dryer, 140℃ / 40min, control moisture content ≤0.3%), remove iron by magnetic separation, and decarburize by acid washing.

[0064] S2: Compaction (20MPa).

[0065] S3: First sintering: Gradient heating, holding at 1250℃ for 2.5h, then cooling in the furnace to 800℃ and forced air cooling to obtain the sintered body.

[0066] S4: Crush the sintered body into 10-20mm particles; add glass powder (5.0% of the total mass of crushed particles, softening point 700℃) and zinc stearate (the amount added is 50% of the amount of zinc stearate used in the first sintering) and mix evenly.

[0067] S5: Second sintering: Vacuum degree 10 -3 Pa, sintered at 1150℃ for 2.5h, cooled, to obtain the machine tool moving crossbeam.

[0068] Comparative Example 8 This example provides a machine tool moving part, the manufacturing method of which includes the following steps: S1: The first sintering raw materials (including 53 parts silicon dioxide, 16.5 parts aluminum oxide, 8 parts calcium oxide, 5 parts magnesium oxide, 8 parts ferric oxide, 0.8 parts titanium dioxide, 2.3 parts potassium oxide, and 3.8 parts sodium oxide) and the first sintering additives: borax (1.8% of the total mass of the first sintering raw materials), calcium fluoride (1.5% of the total mass of the first sintering raw materials), starch (0.8% of the total mass of the first sintering raw materials), and zinc stearate (0.2% of the total mass of the first sintering raw materials) are mixed evenly, dried (fluidized bed dryer, 140℃ / 40min, controlling the moisture content ≤0.3%), magnetically separated to remove iron, and acid-washed to remove carbon.

[0069] S2: Compaction (20MPa).

[0070] S3: First atmospheric pressure sintering: Gradient heating, holding at 1250℃ for 2.5h, then cooling in the furnace to 800℃ and forced air cooling to obtain the sintered body.

[0071] S4: Crush the sintered body into 10-20mm particles; add glass powder (5.0% of the total mass of crushed particles, softening point 700℃), borax (addition amount is 50% of the amount of borax used in the first sintering), calcium fluoride (addition amount is 50% of the amount of calcium fluoride used in the first sintering), starch (addition amount is 50% of the amount of starch used in the first sintering), and zinc stearate (addition amount is 50% of the amount of zinc stearate used in the first sintering) and mix evenly.

[0072] S5: Second atmospheric pressure sintering: sintering at 1150℃ for 2.5h, then cooling to obtain the machine tool moving crossbeam.

[0073] Comparative Example 9 This example provides a machine tool moving part, the manufacturing method of which includes the following steps: S1: Mix the first sintering raw materials (53 parts silicon dioxide, 16.5 parts aluminum oxide, 8 parts calcium oxide, 5 parts magnesium oxide, 8 parts ferric oxide, 0.8 parts titanium dioxide, 2.3 parts potassium oxide, and 3.8 parts sodium oxide) with the first sintering additives: borax (1.8% of the total mass of the first sintering raw materials), calcium fluoride (1.5% of the total mass of the first sintering raw materials), starch (0.8% of the total mass of the first sintering raw materials), and zinc stearate (0.2% of the total mass of the first sintering raw materials) evenly, dry (fluidized bed dryer, 140℃ / 40min, control moisture content ≤0.3%), remove iron by magnetic separation, and decarburize by acid washing.

[0074] S2: Compaction (20MPa).

[0075] S3: First sintering: Gradient heating, holding at 1250℃ for 2.5h, then cooling in the furnace to 800℃ and forced air cooling to obtain the sintered body.

[0076] S4: Coat the surface of the sintered body with an appropriate amount of glass powder.

[0077] S5: Second sintering: Vacuum degree 10 -3 Pa, sintered at 1150℃ for 2.5h, cooled, to obtain the machine tool moving crossbeam.

[0078] Table 1 Performance parameters of the moving crossbeam in the embodiments and comparative examples

[0079] (Note: The damping ratio (logarithmic decay rate) was measured using the free beam vibration decay method.) According to Table 1, we can see that: 1. Regarding porosity and density (bulk density).

[0080] The porosity of Examples 1-4 was 2.2-3.0%, and the bulk density was 2.68-2.78 g / cm³, which met the optimized target (2-4%, 2.6-2.8 g / cm³).

[0081] Comparative Example 1 (single sintering) has a porosity of 12% and a density of only 2.35 g / cm³, indicating that single sintering cannot effectively expel closed-pore gases.

[0082] Comparative Example 3 (without glass powder) had a porosity of 7.5% and a density of 2.48 g / cm³, while Example 1 (with glass powder) had a porosity of 2.8%, indicating that glass powder can fill the gaps between particles and significantly improve density.

[0083] Comparative Example 4 (without additives) had a porosity of 5.5% and a density of 2.58 g / cm³, which was still higher than that of Example 1, indicating that additives (sintering aid, depore-reducing agent, surfactant) can synergistically reduce porosity.

[0084] Comparative Example 8 (sintered at atmospheric pressure) had a porosity of 6.5% and a density of 2.52 g / cm³, which was worse than Example 1, indicating that a vacuum environment is conducive to gas expulsion.

[0085] Comparative Example 9 (without breakage) had a porosity of 9% and a density of 2.40 g / cm³, which was much worse than Example 1 (2.8%, 2.72 g / cm³), indicating that breakage is the key to opening closed pores and releasing gas.

[0086] 2. Regarding mechanical properties.

[0087] Examples 1-4 have a flexural strength of 58-68 MPa, which meets the requirements for machine tool moving parts (≥45 MPa). Among them, Example 2 (high glass powder + high sintering aid) has the highest strength (68 MPa).

[0088] Comparative Example 1 (single-time sintering) has a strength of only 35 MPa, and Comparative Example 2 (resin bonding) has a strength of only 25 MPa, neither of which meets the requirements for use.

[0089] Comparative Example 3 (without glass powder) had a strength of 48 MPa, and Comparative Example 4 (without additives) had a strength of 55 MPa, both lower than that of Example 1 (62 MPa), indicating that glass powder and additives synergistically enhance strength.

[0090] Comparative Examples 5-7 (with missing adjuvants) had a strength of 56-58 MPa, slightly lower than Example 1 (62 MPa), indicating that the combined use of the three adjuvants yielded the best results.

[0091] Comparative Example 8 (sintered at atmospheric pressure) had a strength of 46 MPa, and Comparative Example 9 (without breakage) had a strength of 40 MPa, which is much lower than that of the Example, indicating that vacuum and breakage are crucial for improving strength.

[0092] 3. Regarding water absorption rate.

[0093] Examples 1-4 showed water absorption rates of 0.7-1.1%, all ≤1.1%, meeting the requirements of precision machine tools for low moisture absorption deformation. Comparative Examples 1 (4.5%), 2 (6.8%), 8 (2.5%), and 9 (3.2%) all showed higher water absorption rates than the examples, indicating that high water absorption rates can lead to dimensional instability.

[0094] 4. Regarding damping performance.

[0095] The damping ratios of Examples 1-4 ranged from 0.018 to 0.023, with Example 3 (0.5% starch, secondary sintering at 1150℃ / 2.5h) showing the highest (0.023) and Example 2 (2% ammonium bicarbonate, secondary sintering at 1150℃ / 3h) showing the lowest (0.018). This indicates that the damping ratio depends not only on the addition of a pore-reducing agent but also on the type and amount of the pore-reducing agent, as well as the secondary sintering temperature / time. Example 1 (0.82% starch, 1150℃ / 2.5h) had a damping ratio of 0.020, falling between the two extremes, demonstrating that more pore-reducing agent does not necessarily result in higher damping; process matching is more important.

[0096] Comparative Example 2 (resin bonding) had the highest damping ratio (0.028), but its strength was extremely low, rendering it useless. The damping ratios of the other comparative examples were all lower than those of Examples 1-4, demonstrating that the embodiments of the present invention achieved good damping while ensuring strength.

[0097] 5. Regarding the linear expansion coefficient.

[0098] Examples 1-4: Linear expansion coefficient 5.8-6.5 × 10⁻⁴ -6 The coefficient of thermal expansion (C / K) was lower than that of Comparative Example 1 (7.8), Comparative Example 8 (7.2), and Comparative Example 9 (7.5), indicating good temperature stability. Comparative Example 2, due to its resin content, had the highest coefficient of thermal expansion (8.5) and poor thermal stability.

[0099] 6. Example 2 (high glass powder + high sintering aid) exhibits the best performance in terms of strength, density, and thermal expansion, making it suitable for moving beams requiring high rigidity. Example 3 (containing starch-based anti-pore agent, with a shorter secondary sintering and holding time) provides the best damping, making it suitable for moving beams with high vibration reduction requirements. Example 1 achieves a good balance among various indicators, making it suitable for most application scenarios.

[0100] This invention successfully prepared ceramic-based machine tool moving parts with high density, high strength, low water absorption, high damping, and low thermal expansion through a synergistic process involving a first sintering of raw materials (aluminosilicate system), glass powder, three additives (sintering aid, pore-reducing agent, and surfactant), a second vacuum sintering process, and crushing. Examples 1-4 show significantly better performance than Comparative Examples 1-9, which lack any key component or process, in terms of porosity, density, strength, water absorption, damping, and thermal expansion. Crushing and high-temperature second vacuum sintering are key to reducing porosity. The glass powder fully melts and fills gaps at the second high temperature, the vacuum environment promotes gas expulsion, the sintering aid lowers the sintering temperature and promotes densification, the pore-reducing agent promotes degassing and densification while appropriately retaining submicron-level closed pores to maintain damping performance (requires matching with the sintering process), and the surfactant reduces bubble retention. This technical solution provides a high-performance, process-controllable physical ceramic material solution for high-end CNC machine tool moving parts.

[0101] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-damping ceramic-based machine tool moving part, characterized in that: Made from raw materials including the following components: Raw materials for the first sintering: 52.5-53.5 parts silicon dioxide, 16.2-16.8 parts aluminum oxide, 7.8-8.2 parts calcium oxide, 4.8-5.2 parts magnesium oxide, 7.8-8.2 parts ferric oxide, 0.6-1.0 parts titanium dioxide, 2.1-2.5 parts potassium oxide, and 3.6-4.0 parts sodium oxide; And the first sintering aid, including: Borax, used at a rate of 1.5-2% of the total mass of the raw materials for the first sintering. Calcium fluoride, used at a rate of 1-2% of the total mass of the raw materials for the first sintering. The pore-reducing agent is selected from starch or ammonium bicarbonate. The amount of starch used is 0.5-1% of the total mass of the raw materials for the first sintering, and the amount of ammonium bicarbonate used is 1-3% of the total mass of the raw materials for the first sintering. The surfactant, zinc stearate, is used at a rate of 0.15-0.25% of the total mass of the raw materials used in the first sintering. Second sintering additives: The amount of glass powder used is 4-6% of the total mass of the crushed particles after the first sintering. The softening point of the glass powder is 700-800℃. In addition, supplementary additives, including borax, calcium fluoride, pore-reducing agent and surfactant, are added, with the amount of each supplementary additive being 1 / 3 to 1 / 2 of the amount of the corresponding additive used in the first sintering.

2. The high-damping ceramic-based machine tool moving part according to claim 1, characterized in that: The moving part is formed by mixing, compacting and degassing the raw materials for the first sintering, and then sintering for the first time at a temperature of 1100-1250℃.

3. The high-damping ceramic-based machine tool moving part according to claim 2, characterized in that: After the first sintering, the sintered body is broken down to a particle size of 10-20mm, and then a second sintering is carried out.

4. The high-damping ceramic-based machine tool moving part according to claim 1, characterized in that: The second sintering is vacuum sintering, with the vacuum level controlled at no less than 10. -3 Pa, temperature 1050-1150℃, heat preservation time 2-3 hours.

5. The high-damping ceramic-based machine tool moving part according to claim 1, characterized in that: The first sintering process employs a gradient temperature rise process, including: From room temperature to 300℃, the heating rate is 3-8℃ / min; 300-800℃, heating rate 2-5℃ / min; 800-1250℃, heating rate 1-3℃ / min; It is sintered at 1250℃ and held at that temperature for 2-3 hours; then cooled to 800℃ in the furnace and forced to air cool.

6. The high-damping ceramic-based machine tool moving part according to claim 1, characterized in that: The raw materials are pretreated before the first sintering, including: Dry to a moisture content of ≤0.3% at a temperature of 120-150℃ for 30-45 minutes. Magnetic separation removes iron until the iron content is <0.5%; Acid washing and decarbonization resulted in organic matter residue of <0.1%.

7. The high-damping ceramic-based machine tool moving part according to claim 1, characterized in that: The ceramic-based machine tool moving parts are worktables, slides, crossbeams, spindle boxes, or tool holders.

8. The method for preparing the high-damping ceramic-based machine tool moving part according to any one of claims 1-7, characterized in that: Includes the following steps: S1: Weigh the raw materials and additives for the first sintering according to the proportion, mix them evenly to obtain the mixture; S2: Compact the mixture and expel the gas; S3: The compacted mixture is sintered for the first time at a temperature of 1100-1250℃ for 2-3 hours. After cooling to 800℃ in the furnace, it is forced to air-cool to obtain the sintered body. S4: The sintered body is crushed to a particle size of 10-20mm to obtain crushed particles; S5: Add a second sintering additive to the crushed particles. The second sintering additive includes glass powder and supplementary additives. The amount of glass powder added is 4-6% of the total mass of the crushed particles. The softening point of the glass powder is 700-800℃. The supplementary additives include borax, calcium fluoride, pore-reducing agent and surfactant. The amount of each supplementary additive is 1 / 3 to 1 / 2 of the amount of the corresponding additive in the first sintering additive. S6: The crushed particles after adding the second sintering additives are subjected to a second vacuum sintering, with a vacuum degree of not less than 10. - 3 Pa, sintering temperature is 1050-1150℃, hold for 2-3 hours, and then cool to obtain the finished high-damping ceramic-based machine tool moving part.

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