CN116445830A - A kind of anti-creep high thermal conductivity graphene modified high-speed steel material and preparation method thereof - Google Patents

Abstract

The invention discloses a creep-resistant high-thermal conductivity graphene modified high-speed steel material and a preparation method thereof. Contains the following mass percentage elements: Co 15-30%, the total amount of Mo and W is 10-20% and the W content is <8%, Cr 5-10%, Ni 5-7%, Al 5-8%, Si 1.5% ～2%, V 0.5～1%, Ta 0.5～1%, Ce 0.1～0.3%, Sc 0.1～0.2%, graphene 0.5～1.5%, and the balance is iron. Based on the synergistic effect of in-situ generated intermetallic compounds and graphene materials in this composite material, the strength, toughness and thermal conductivity of the material under high temperature conditions are greatly improved under the premise of ensuring the hardness of the material, and the material is endowed with excellent high-temperature mechanical properties. The composite material fully mixes the raw materials and improves its sintering activity through ultrasonic dispersion and high-energy ball milling. Under the synergistic effect of subsequent heat treatment, nano-scale intermetallic compounds are produced to obtain a significant strengthening effect.

Description

A kind of anti-creep high thermal conductivity graphene modified high-speed steel material and preparation method thereof

technical field

The invention relates to a high-speed steel material, in particular to a creep-resistant high-thermal-conductivity graphene-modified high-speed steel material and a preparation method thereof, belonging to the field of special alloy preparation.

Background technique

With the vigorous development of industries such as home building materials, information optoelectronics, automobile industry and smart devices, 3D curved glass has attracted much attention because of its unique optical properties, thermal stability and mechanical properties. For example, in the field of smart phones, 3D curved glass is widely used in high-end models of mobile phones because of its lightness, transparency and cleanliness, fuller visual effects, and more ergonomic touch. Relevant data show that 3D glass for smart phones The penetration rate of cover plates is increasing year by year, reaching about 27% in 2020, and the future market size is promising. At the same time, 3C product designs, such as tablet computers, head-mounted VR devices, smart watches and other wearable smart products, vehicle central control and portable dashboards, and other scenarios have gradually seen the application of 3D glass, making the market demand for 3D glass Quantity and precision requirements are constantly improving, which in turn drives the development of the entire industrial chain. However, due to the special complex geometric dimensions, the processing difficulty of 3D curved glass is much higher than that of ordinary flat glass.

At present, 3D curved glass is mainly prepared by cold processing and hot forming technology, but the expensive equipment cost and long processing cycle of cold processing technology limit its application in the field of small size and large output civil demand. The widely used thermoforming technology is to process rheological deformation of the heated high viscoelastic state glass through a forming mold, so as to prepare curved glass with high shape and dimensional accuracy. The core equipment of thermoforming is 3D hot bending glass machine. The hot bending process can be summarized as heating the heating tube to provide a heat source, and the heat and pressure are transferred to the glass through the heating plate, vapor chamber, and mold in turn, and then the hot bending is completed. Obviously, the heating plate is the initial part of heat transfer and force transfer in the hot bending forming process. Its temperature control accuracy, temperature uniformity, and force transfer uniformity determine the accuracy of the entire hot bending system and hot bending products. However, the 310S stainless steel (or similar grade) heating plate used in the current hot bending equipment has the problems of low high-temperature hardness, low thermal conductivity, and large thermal expansion coefficient. The thermal conductivity of 310S at room temperature is only 12-15W/(m.k), the heat transfer rate is slow, the uniformity of the temperature field is limited, and the burden on the heating pipe is increased; The hot plate and the mold are much higher, and deformation is caused by the mismatch of thermal expansion coefficient at high temperature, and it is difficult to ensure high plane accuracy in long-term use; at the same time, the service hardness of 310S is extremely low under long-term high temperature conditions, and the hardness is low when used at 600 ° C ~ 900 ° C Below 10HRC, the material is very easy to soften and cause creep deformation. To sum up, the 310S heating plate adds uncertainty and instability to the hot bending system, which cannot further improve the accuracy of the equipment and limits the production efficiency. However, no other suitable alternative materials have been found in the industry. In addition, since the heating plate material usually serves in a high temperature environment higher than 600 °C, the problem of high temperature oxidation of the material needs to be considered. Therefore, there is an urgent need for a new heating plate material with high thermal conductivity, high temperature strength and hardness, small thermal expansion coefficient and good oxidation resistance.

Contents of the invention

Aiming at the problems existing in the prior art, the first object of the present invention is to provide a creep-resistant high-thermal-conductivity graphene-modified high-speed steel material, which is based on the synergistic effect between components and utilizes the in-situ generated The synergistic strengthening of the intermetallic compound and the dispersed graphene can greatly improve the strength, toughness, stability and thermal conductivity of the material on the premise of ensuring the high temperature hardness of the material.

The second object of the present invention is to provide a method for preparing a creep-resistant and high-thermal-conductivity graphene-modified high-speed steel material. The method fully mixes graphene and other metal raw materials through batch-by-batch dispersion and high-energy ball milling to improve the quality of the material. The sintering activity promotes the uniform precipitation of nano-scale intermetallic compounds through heat treatment, thereby improving the strength and toughness of the material.

In order to achieve the above-mentioned technical purpose, the present invention provides a kind of anti-creep high thermal conductivity graphene modified high-speed steel material, comprising the following mass percentage elements: Co 15-30%, the total amount of Mo and W is 10-20% and W Content<8%, Cr 5~10%, Ni 5~7%, Al 5~8%, Si 1.5~2%, V 0.5~1%, Ta 0.5~1%, Ce 0.1~0.3%, Sc0.1 ~0.2%, graphene is 0.5~1.5%, and the balance is iron.

The intermetallic compound in the creep-resistant high-thermal-conductivity graphene-modified high-speed steel material provided by the present invention is generated in situ by elements such as Fe, Co, Mo, W, Cr, Al, etc. Compared with the carbide-strengthened phase in traditional high-speed steel, Intermetallic compounds are not easy to aggregate and overage at high temperatures, and maintain a coherent/semi-coherent interface relationship with the α-Fe matrix, which endows them with high high-temperature strength and hardness, excellent thermal conductivity, small thermal expansion coefficient and better toughness. At the same time, an appropriate amount of graphene material is added to the intermetallic compound-strengthened high-speed steel matrix to further enhance the toughness, thermal conductivity and oxidation resistance of high-speed steel materials by utilizing the characteristics of graphene's high strength, high thermal conductivity and high stability.

As a preferred solution, the high-speed steel material contains the following mass percentage elements: Co18-27%, the total amount of Mo and W is 13-18% and the W content is <6%, Cr 7-10%, Ni 5-7 %, Al 6-8%, Si 1.5-2%, V0.5-1%, Ta 0.5-1%, Ce 0.1-0.3%, Sc 0.1-0.2%, graphene 1-1.5%, and the balance is Fe; the high-speed steel material includes an in-situ strengthening phase composed of intermetallic compounds and highly dispersed graphene.

In the high-speed steel material provided by the present invention, it is necessary to strictly control the addition amount of Mo and W elements according to the above requirements. Due to the higher melting point and larger specific gravity of W, when the W content is high, the temperature required for sintering and heat treatment is higher, that is, more energy consumption, higher cost, and it is not conducive to the demand for light weight.

As a preferred solution, the intermetallic compound is A ₇ B ₆ type and/or AB ₂ type intermetallic compound.

As a preferred solution, the graphene is nickel-coated graphene.

The invention uses nickel-plated graphene as the graphene raw material, which can minimize the interaction with iron at high temperature, ensure the integrity of the graphene, and meanwhile have good interface wettability. In this composite high-speed steel material, on the one hand, graphene inhibits grain growth and hinders dislocation movement to strengthen the material and improve mechanical properties; To enhance the thermal conductivity of the overall material.

The invention also provides a preparation method of a creep-resistant and high-thermal-conductivity graphene-modified high-speed steel material. The graphene is dispersed in a ball milling medium, the remaining metal element powder is added to continue the dispersion, and then ball milled and dried with additives in sequence. Get the mix.

As a preferred scheme, the mixed material is obtained by successively sieving, cold pressing, sintering and heat treatment.

As a preferred solution, the dispersion method is ultrasonic dispersion, and the conditions are: the ultrasonic power is 100-200W, and the time is 20-40min. The preparation method provided by the invention can realize uniform dispersion of graphene raw material and metal mixed powder, and obtain a graphene-reinforced composite material with high density and uniform tissue distribution.

As a preferred solution, the ball milling medium is at least one of water, ethanol, propanol and petroleum ether.

As a preferred solution, the ball milling medium is ethanol.

As a preferred solution, the ball milling method is wet high-energy ball milling, and the conditions are: under a protective atmosphere, the ball-to-material ratio is 4-7:1, the rotating speed is 240-340r/min, and the time is 72-96h; The protective atmosphere is high-purity nitrogen and/or high-purity argon.

As a preferred solution, the carbon black is added in an amount of 0.2-0.5% by weight of the mixture.

In the present invention, carbon black is added for carbon-oxygen reaction with adsorbed oxygen during the sintering process. However, it should be noted that carbon black will be completely consumed during the sintering process and does not participate in the composition of the final product.

As a preferred solution, the molding agent is at least one of paraffin, PEG and PVB.

As a preferred solution, the added amount of the molding agent accounts for 3-6% of the mass percentage of the mixture.

As a preferred solution, the particle size of the material obtained by screening the mixture is ≤40 mesh.

As a preferred solution, the pressure of the cold pressing is 100-200 MPa.

As a preferred solution, the sintering is temperature-programmed vacuum sintering.

As a preferred solution, the sintering conditions are: heating from room temperature to 1300-1400° C. at a rate of 5-10° C./min, keeping the temperature for 2-4 hours, and vacuum degree ≤ 0.01 Pa.

As a preferred solution, the heat treatment includes solution treatment and aging treatment.

As a preferred solution, the solution treatment conditions are: at 1150-1250° C., heat preservation for 0.5-1.5 hours, and gas quenching to room temperature.

As a preferred solution, the conditions of the aging treatment are: under a protective atmosphere, the temperature is 700-1000° C., the time is 3-5 hours, and the aging treatment is cooled to room temperature with the furnace. The purpose of aging treatment is to promote the uniform precipitation and growth of nano-scale intermetallic compounds in high-speed steel materials, thereby improving the strength, toughness and stability of materials.

Compared with the prior art, the beneficial technical effects of the present invention are as follows:

1) The high-speed steel material provided by the present invention is based on the synergy between the various components. The intermetallic compound formed in situ during the aging process has a coherent or semi-coherent relationship with the matrix, which can effectively strengthen the hardness of the material. The added Cr , Al and Si elements can form a dense oxide film structure with the Fe matrix, further improving the high temperature oxidation resistance of the material, and the rare earth elements Ce and Sc can effectively absorb impurities such as oxygen and sulfur, activate sintering, and purify the grain boundary, thereby effectively improving high temperature stability and toughness of the material.

2) The room temperature peak hardness of the high-speed steel material provided by the present invention is 85-87HRA, the bending strength is 2800-3500MPa, the impact toughness is 10-15J/cm ² , and the thermal conductivity at 700°C is 45-50W/(m·K) , 800°C high-temperature hardness is 81-83.5HRA, 600°C aging 200h hardness is 82-85HRA, and the thermal expansion coefficient is 20-30% lower than that of 310S stainless steel. At the same time, the high-speed steel of the present invention can adjust the corresponding properties through the heat treatment process, for example, the impact toughness can be increased to 60-80J/cm ² through aging at 900°C for 3 hours. That is, the high-speed steel described in the present invention has the characteristics of high hardness, excellent thermal conductivity and small thermal expansion coefficient, and can realize comprehensive performance optimization.

3) The high-speed steel material of the present invention can quickly transfer the heat of the heating pipe, reduce its load power, and improve the overall service life of the heating system; it has excellent dimensional stability during long-term high-temperature service, can maintain high hardness and high strength, and reduces Creep deformation, thereby improving the precision and production efficiency of the hot bending system.

Description of drawings

Fig. 1 is the scanning electron microscope microstructure picture of embodiment 1;

FIG. 2 is a scanning electron microscope microstructure picture of Comparative Example 1.

Specific implementation form

In order to better understand the present invention, the present invention will be further described below in conjunction with the examples, but the embodiments of the present invention are not limited thereto.

Among the following raw materials, the particle size of metal powder D50 is 1-10 μm, and the particle size of Ce powder and Sc powder is 200-400 mesh.

In the following cases, the ball milling media mentioned are all absolute ethanol, and based on the raw material powder, the amount of ball milling media is 0.8mL/g; the ball milling speed is 300r/min.

Example 1

(1) Ultrasonic dispersion of raw materials

Add 1.4wt.% nickel-plated graphene raw material to absolute ethanol and carry out ultrasonic vibration for 30min (ultrasonic power is 150W), then add the remaining metal elements and rare earth element powders weighed according to the proportion, and jointly ultrasonically vibrate for 30min to obtain a uniform Dispersed mixed powder in absolute ethanol solution.

(2) Raw materials are mixed by high-energy ball milling

Add 0.3wt.% carbon black and 5wt.% paraffin wax molding agent to step (1) in the anhydrous ethanol solution of mixed powder, and then put them together into a ball mill tank that can be fed into argon protection for wet ball milling. The ball milling medium is Water ethanol, the dosage is 0.8mL/g, the ball-to-material ratio is 5:1, the ball milling speed is 300r/min, and the ball milling time is 80h. After the ball milling, dry in a vacuum drying oven, set the temperature at 82° C., and dry for 5 hours.

(3) Compression molding

The mixed powder dried in the step (2) was sieved through 40 meshes, and then cold-molded with a pressing pressure of 150 MPa to obtain a green compact.

(4) Vacuum sintering

The compact was placed in a vacuum sintering furnace for vacuum sintering, the vacuum degree was controlled at less than 0.01Pa, the temperature was raised from room temperature to the highest sintering temperature of 1350°C at 8°C/min, the holding time was 3h, and the sintered compact was obtained by cooling to room temperature with the furnace.

(5) heat treatment

The sintered billet was placed in a vacuum quenching furnace for solution treatment. The solution treatment temperature was 1220°C and the holding time was 1h. After solution treatment, it was cooled to room temperature by gas quenching. Then aging treatment was carried out in an atmosphere furnace fed with nitrogen protection, the aging temperature was 800°C, and the aging time was 4h. That is, the high-speed steel material for the heating plate of the hot-bending glass machine is obtained.

Example 2

(1) Ultrasonic dispersion of raw materials

Add 1.0wt.% nickel-plated graphene raw material to absolute ethanol and carry out ultrasonic vibration for 30min (ultrasonic power is 150W), then add the remaining metal elements and rare earth element powders weighed according to the proportion, and ultrasonic vibration for 30min together to obtain a uniform Dispersed mixed powder in absolute ethanol solution.

(2) Raw materials are mixed by high-energy ball milling

Add 0.4wt.% carbon black and 5wt.% paraffin wax molding agent to step (1) in addition to the mixed powder anhydrous ethanol solution, and then put them together into a ball mill tank that can be fed into argon protection for wet ball milling. The ball milling medium is Water ethanol, the dosage is 0.8mL/g, the ball-to-material ratio is 5:1, the ball milling speed is 300r/min, and the ball milling time is 80h. After the ball milling, dry in a vacuum drying oven, set the temperature at 82° C., and dry for 5 hours.

(3) Compression molding

The mixed powder dried in the step (2) was sieved through 40 meshes, and then cold-molded with a pressing pressure of 150 MPa to obtain a green compact.

(4) Vacuum sintering

The compact was placed in a vacuum sintering furnace for vacuum sintering, the vacuum degree was controlled at less than 0.01Pa, the temperature was raised from room temperature to the highest sintering temperature of 1330°C at 8°C/min, the holding time was 3h, and the sintered compact was obtained by cooling to room temperature with the furnace.

(5) heat treatment

The sintered billet was placed in a vacuum quenching furnace for solution treatment. The solution treatment temperature was 1210° C., and the holding time was 1 hour. After solution treatment, it was cooled to room temperature by gas quenching. Then aging treatment was carried out in an atmosphere furnace fed with nitrogen protection, the aging temperature was 800°C, and the aging time was 4h. That is, the high-speed steel material for the heating plate of the hot-bending glass machine is obtained.

Example 3

(1) Ultrasonic dispersion of raw materials

Add 0.5wt.% nickel-plated graphene raw material to absolute ethanol and carry out ultrasonic vibration for 30min (ultrasonic power is 150W), then add the remaining metal elements and rare earth element powders weighed according to the proportion, and ultrasonic vibration for 30min together to obtain a uniform Dispersed mixed powder in absolute ethanol solution.

(2) Raw materials are mixed by high-energy ball milling

Add 0.3wt.% carbon black and 5wt.% paraffin wax molding agent to step (1) in the anhydrous ethanol solution of mixed powder, and then put them together into a ball mill tank that can be fed into argon protection for wet ball milling. The ball milling medium is Water ethanol, the dosage is 0.8mL/g, the ball-to-material ratio is 5:1, the ball milling speed is 300r/min, and the ball milling time is 85h. After the ball milling, dry in a vacuum drying oven, set the temperature at 82° C., and dry for 5 hours.

(3) Compression molding

The mixed powder dried in the step (2) was sieved through 40 meshes, and then cold-molded with a pressing pressure of 150 MPa to obtain a green compact.

(4) Vacuum sintering

The compact was placed in a vacuum sintering furnace for vacuum sintering, the vacuum degree was controlled at less than 0.01Pa, the temperature was raised from room temperature to the highest sintering temperature of 1300°C at 8°C/min, the holding time was 3h, and the sintered compact was obtained by cooling to room temperature with the furnace.

(5) heat treatment

The sintered billet was placed in a vacuum quenching furnace for solution treatment. The solution treatment temperature was 1190° C. and the holding time was 1 hour. After solution treatment, it was cooled to room temperature by gas quenching. Then, aging treatment was carried out in an atmosphere furnace fed with nitrogen protection, the aging temperature was 750° C., and the aging time was 4 hours. That is, the high-speed steel material for the heating plate of the hot-bending glass machine is obtained.

Example 4

(1) Ultrasonic dispersion of raw materials

Add 1.5wt.% nickel-plated graphene raw material to absolute ethanol and carry out ultrasonic vibration for 30min (ultrasonic power is 150W), then add the remaining metal elements and rare earth element powders weighed according to the proportion, and ultrasonic vibration for 30min together to obtain a uniform Dispersed mixed powder in absolute ethanol solution.

(2) Raw materials are mixed by high-energy ball milling

Add 0.3wt.% carbon black and 5wt.% paraffin wax molding agent to step (1) in the anhydrous ethanol solution of mixed powder, and then put them together into a ball mill tank that can be fed into argon protection for wet ball milling. The ball milling medium is Water ethanol, the dosage is 0.8mL/g, the ball-to-material ratio is 5:1, the ball milling speed is 300r/min, and the ball milling time is 80h. After the ball milling, dry in a vacuum drying oven, set the temperature at 82° C., and dry for 5 hours.

(3) Compression molding

The mixed powder dried in the step (2) was sieved through 40 meshes, and then cold-molded with a pressing pressure of 150 MPa to obtain a green compact.

(4) Vacuum sintering

Put the compact in a vacuum sintering furnace for vacuum sintering, the vacuum degree is controlled at less than 0.01Pa, the temperature is raised from room temperature to the highest sintering temperature of 1380°C at 8°C/min, the holding time is 3h, and the sintered compact is obtained by cooling to room temperature with the furnace.

(5) heat treatment

The sintered billet was placed in a vacuum quenching furnace for solution treatment. The solution treatment temperature was 1270°C and the holding time was 1h. After solution treatment, it was cooled to room temperature by gas quenching. Then, aging treatment was carried out in an atmosphere furnace fed with nitrogen protection, the aging temperature was 850° C., and the aging time was 4 hours. That is, the high-speed steel material for the heating plate of the hot-bending glass machine is obtained.

Example 5

(1) Ultrasonic dispersion of raw materials

Add 0.9wt.% nickel-plated graphene raw material to absolute ethanol and carry out ultrasonic vibration for 30min (ultrasonic power is 150W), then add the remaining metal elements and rare earth element powders weighed according to the proportion, and ultrasonic vibration for 30min together to obtain a uniform Dispersed mixed powder in absolute ethanol solution.

(2) Raw materials are mixed by high-energy ball milling

Add 0.3wt.% carbon black and 5wt.% paraffin wax molding agent to step (1) in the anhydrous ethanol solution of mixed powder, and then put them together into a ball mill tank that can be fed into argon protection for wet ball milling. The ball milling medium is Water ethanol, the dosage is 0.8mL/g, the ball-to-material ratio is 5:1, the ball milling speed is 300r/min, and the ball milling time is 80h. After the ball milling, dry in a vacuum drying oven, set the temperature at 82° C., and dry for 5 hours.

(3) Compression molding

The mixed powder dried in the step (2) was sieved through 40 meshes, and then cold-molded with a pressing pressure of 150 MPa to obtain a green compact.

(4) Vacuum sintering

The compact was placed in a vacuum sintering furnace for vacuum sintering, the vacuum degree was controlled at less than 0.01Pa, the temperature was raised from room temperature to the highest sintering temperature of 1350°C at 8°C/min, the holding time was 3h, and the sintered compact was obtained by cooling to room temperature with the furnace.

(5) heat treatment

The sintered billet is placed in a vacuum quenching furnace for solution treatment. The solution treatment temperature is 1200°C and the holding time is 1h. After the solution treatment, it is cooled to room temperature by gas quenching. Then aging treatment was carried out in an atmosphere furnace fed with nitrogen protection, the aging temperature was 800°C, and the aging time was 4h. That is, the high-speed steel material for the heating plate of the hot-bending glass machine is obtained.

Comparative example 1

The preparation process adopted in this comparative example is exactly the same as that of Example 1, and the only difference is that the components are different.

Comparative example 2

The preparation process adopted in this comparative example is exactly the same as that of Example 1, and the only difference is that the components are different.

Comparative example 3

The preparation process adopted in this comparative example is exactly the same as that of Example 1, and the only difference is that the components are different.

Comparative example 4

The preparation process adopted in this comparative example is exactly the same as that of Example 1, and the only difference is that the components are different.

Comparative example 5

(1) Ultrasonic dispersion of raw materials

Add 1.4wt.% nickel-plated graphene raw material to absolute ethanol and carry out ultrasonic vibration for 30min (ultrasonic power is 150W), then add the remaining metal elements and rare earth element powders weighed according to the proportion, and jointly ultrasonically vibrate for 30min to obtain a uniform Dispersed mixed powder in absolute ethanol solution.

(2) Raw materials are mixed by high-energy ball milling

Add 0.3wt.% carbon black and 5wt.% paraffin wax molding agent to step (1) in the anhydrous ethanol solution of mixed powder, and then put them together into a ball mill tank that can be fed into argon protection for wet ball milling. The ball milling medium is Water ethanol, the dosage is 0.8mL/g, the ball-to-material ratio is 5:1, the ball milling speed is 300r/min, and the ball milling time is 80h. After the ball milling, dry in a vacuum drying oven, set the temperature at 82° C., and dry for 5 hours.

(3) Compression molding

The mixed powder dried in the step (2) was sieved through 40 meshes, and then cold-molded with a pressing pressure of 150 MPa to obtain a green compact.

(4) Vacuum sintering

Put the compact in a vacuum sintering furnace for vacuum sintering, the vacuum degree is controlled at less than 0.01Pa, the temperature is raised from room temperature to the highest sintering temperature of 1250°C at 8°C/min, the holding time is 3h, and the sintered compact is obtained by cooling to room temperature with the furnace.

(5) heat treatment

The sintered billet is placed in a vacuum quenching furnace for solution treatment. The solution treatment temperature is 1200°C and the holding time is 1h. After the solution treatment, it is cooled to room temperature by gas quenching. Then aging treatment was carried out in an atmosphere furnace fed with nitrogen protection, the aging temperature was 800°C, and the aging time was 4h. That is, the high-speed steel material for the heating plate of the hot-bending glass machine is obtained.

Comparative example 6

(1) Raw materials are mixed by high-energy ball milling

Put the metal powder, rare earth powder and nickel-plated graphene raw material and additionally added 0.3wt.% carbon black, 5wt.% paraffin wax molding agent into the ball mill tank that can be passed into argon protection for wet ball milling according to the proportion, and the ball milling medium It is absolute ethanol, the dosage is 0.8mL/g, the ball-to-material ratio is 5:1, the ball milling speed is 300r/min, and the ball milling time is 80h. After the ball milling, dry in a vacuum drying oven, set the temperature at 82° C., and dry for 5 hours.

(2) Compression molding

The mixed powder dried in the step (2) was sieved through 40 meshes, and then cold-molded with a pressing pressure of 150 MPa to obtain a green compact.

(3) Vacuum sintering

The compact was placed in a vacuum sintering furnace for vacuum sintering, the vacuum degree was controlled at less than 0.01Pa, the temperature was raised from room temperature to the highest sintering temperature of 1350°C at 8°C/min, the holding time was 3h, and the sintered compact was obtained by cooling to room temperature with the furnace.

(5) heat treatment

The sintered billet was placed in a vacuum quenching furnace for solution treatment. The solution treatment temperature was 1220°C and the holding time was 1h. After solution treatment, it was cooled to room temperature by gas quenching. Then aging treatment was carried out in an atmosphere furnace fed with nitrogen protection, the aging temperature was 800°C, and the aging time was 4h. That is, the high-speed steel material for the heating plate of the hot-bending glass machine is obtained.

The ratio of raw material composition in the examples and comparative examples provided by the present invention is shown in Table 1.

Since the mechanical properties of the high-speed steel material described in the present invention are related to the heat treatment process, in order to make a unified comparison, the peak aging process is used to compare the room temperature hardness, flexural strength and impact toughness; the high temperature hardness refers to the real-time test hardness value at 800 ° C for 20 minutes. Table 2 is embodiment and comparative example performance test result.

The composition mass percentage (wt.%) of table 1 embodiment and comparative example

co Mo W Cr Al Ni Si V Ta Ce sc Graphene Fe Example 1 25 15 3 9 8 7 1.8 0.7 0.5 0.2 0.2 1.4 Bal. Example 2 twenty one 12 2 7 6 7 1.6 0.6 0.6 0.2 0.2 1.0 Bal. Example 3 15 9 1 5 5 6 1.5 0.5 0.5 0.1 0.1 0.5 Bal. Example 4 27 13 4 10 7 7 2 0.8 0.8 0.3 0.2 1.5 Bal. Example 5 18 10 5 8 7 7 1.7 0.5 0.6 0.2 0.2 0.9 Bal. Comparative example 1 25 15 3 9 8 7 1.8 0.7 0.5 0.2 0.2 0 Bal. Comparative example 2 25 15 3 9 8 7 1.8 0.7 0.5 0.2 0.2 2.0 Bal. Comparative example 3 twenty one 12 2 7 6 7 1.6 0.6 0.6 0 0 1.0 Bal. Comparative example 4 25 15 3 13 10 10 1.8 0.7 0.5 0.2 0.2 1.4 Bal. Comparative example 5 25 15 3 9 8 7 1.8 0.7 0.5 0.2 0.2 1.4 Bal. Comparative example 6 25 15 3 9 8 7 1.8 0.7 0.5 0.2 0.2 1.4 Bal.

Table 2 embodiment and comparative example performance test result

From the performance results in Table 2, it can be seen that compared with the traditional powder high-speed steel ASP30 and 310S stainless steel, the high-speed steel material prepared by the embodiment of the present invention has excellent high-temperature hardness and tempering resistance, that is, it can maintain excellent microstructure when used at high temperature and dimensional stability; at the same time, a large thermal conductivity can speed up heat transfer, which is beneficial to reduce energy consumption during the hot bending process and improve the uniformity of glass heating. That is, compared with the original heating plate material 310S stainless steel, the high-speed steel material prepared according to the material composition and preparation method of the present invention can improve production accuracy and production efficiency, and has great application prospects. For the comparative examples that are not within the range of material composition or process described in the present invention, the performance is reduced due to defects such as unreasonable composition design, uneven mixing, and low sintering density.

The above descriptions are only preferred embodiments of the present invention, and do not limit the present invention in any way. All simple modifications, changes and equivalent changes made to the above embodiments according to the technical essence of the invention still belong to the protection scope of the technical solution of the present invention.

Claims (10)

1. The creep-resistant high-heat-conductivity graphene modified high-speed steel material is characterized in that: comprises the following elements in percentage by mass: 15-30% of Co, 10-20% of the total amount of Mo and W, less than 8% of W content, 5-10% of Cr, 5-7% of Ni, 5-8% of Al, 1.5-2% of Si, 0.5-1% of V, 0.5-1% of Ta, 0.1-0.3% of Ce, 0.1-0.2% of Sc, 0.5-1.5% of graphene and the balance of iron; the high-speed steel material comprises an in-situ strengthening phase composed of intermetallic compounds and high-dispersion graphene.

2. The creep-resistant high-heat-conductivity graphene-modified high-speed steel material according to claim 1, wherein the creep-resistant high-heat-conductivity graphene-modified high-speed steel material is characterized in that: the high-speed steel material comprises the following elements in percentage by mass: 18-27% of Co, 13-18% of the total amount of Mo and W, less than 6% of W content, 7-10% of Cr, 5-7% of Ni, 6-8% of Al, 1.5-2% of Si, 0.5-1% of V, 0.5-1% of Ta, 0.1-0.3% of Ce, 0.1-0.2% of Sc, 1-1.5% of graphene and the balance of Fe.

3. The creep-resistant high-thermal-conductivity graphene-modified high-speed steel material according to claim 1 or 2, wherein the creep-resistant high-thermal-conductivity graphene-modified high-speed steel material is characterized in that: the intermetallic compound is A ₇ B ₆ And/or AB ₂ A type intermetallic compound; the graphene is nickel-plated graphene.

4. A method for preparing a creep-resistant high-heat-conductivity graphene modified high-speed steel material according to any one of claims 1 to 3, which is characterized in that: dispersing graphene in a ball milling medium, adding residual metal element powder for continuous dispersion, and sequentially performing ball milling and drying with an auxiliary agent to obtain a mixture; and (3) sieving, cold pressing, sintering and heat treating the mixture in sequence to obtain the composite material.

5. The preparation method of the creep-resistant high-heat-conductivity graphene modified high-speed steel material is characterized by comprising the following steps: the dispersion mode is ultrasonic dispersion, and the conditions are as follows: the ultrasonic power is 100-200W, and the time is 20-40 min; the ball milling medium is at least one of water, ethanol, propanol and petroleum ether.

6. The preparation method of the creep-resistant high-heat-conductivity graphene modified high-speed steel material is characterized by comprising the following steps of: the ball milling medium is ethanol; the ball milling mode is wet high-energy ball milling, and the conditions are as follows: under the protective atmosphere, the ball-to-material ratio is 4-7: 1, the rotating speed is 240-340 r/min, and the time is 72-96 h; the protective atmosphere is high-purity nitrogen and/or high-purity argon.

7. The preparation method of the creep-resistant high-heat-conductivity graphene modified high-speed steel material is characterized by comprising the following steps: the addition amount of the carbon black accounts for 0.2 to 0.5 percent of the mass of the mixture; the forming agent is at least one of paraffin, PEG and PVB; the addition amount of the forming agent accounts for 3-6% of the mass percent of the mixture.

8. The preparation method of the creep-resistant high-heat-conductivity graphene modified high-speed steel material is characterized by comprising the following steps: the grain diameter of the material obtained by sieving the mixture is less than or equal to 40 meshes; the pressure of the cold pressing is 100-200 MPa.

9. The preparation method of the creep-resistant high-heat-conductivity graphene modified high-speed steel material is characterized by comprising the following steps: the sintering is temperature programming vacuum sintering, and the sintering conditions are as follows: raising the temperature from room temperature to 1300-1400 ℃ at 5-10 ℃/min, preserving the heat for 2-4 h, and keeping the vacuum degree less than or equal to 0.01Pa.

10. The preparation method of the creep-resistant high-heat-conductivity graphene modified high-speed steel material is characterized by comprising the following steps: the heat treatment comprises solution treatment and aging treatment; the conditions of the solution treatment are as follows: preserving heat for 0.5-1.5 h at 1150-1250 ℃, and cooling to room temperature by gas quenching; the aging treatment conditions are as follows: under the protective atmosphere, the temperature is 700-1000 ℃ and the time is 3-5 h, and the furnace is cooled to the room temperature.