Mixing and grinding assisting device for heat treatment of metal alloy powder

Abstract

The utility model discloses a mixing and grinding aid device for heat treatment of metal alloy powder, which comprises a vacuum system, a rotary transmission system, a fan blade furnace tube and a minimum storage unit. The rotary transmission system drives the fan blade furnace tube and the embedded minimum material storage unit to move at low-speed circumferential rotation, and the contact area between powder materials and gas can be effectively increased or the effective contact probability between the materials can be improved by means of the stirring and grinding effects of internal grinding-assisting grinding balls and grid baffles, so that the reaction process is accelerated, and the reaction efficiency is improved. Meanwhile, the problems of overheating decomposition, insufficient reaction and the like caused by local powder clamping of the tube wall are solved, and compared with an integral furnace tube, the furnace tube is easy to clean and replace, convenient and efficient.

Description

Technical Field

[0001] The utility model belongs to the technical field of metal heat treatment, and in particular relates to a mixing grinding aid device for heat treatment of metal alloy powder. Background Art

[0002] With the continuous development of science and technology, new materials are constantly emerging to bring convenience to people's lives. The performance of materials is closely related to their composition, organization, and processing methods. For metal powders, heat treatment is indispensable.

[0003] There are many purposes for heat treatment of metal powders, which can be used to improve the hardness and strength of materials, optimize the microstructure of materials, and improve the key functional properties of materials. If the reaction between the powder and the atmosphere in the furnace is not involved, traditional heat treatment equipment such as box furnaces and tube furnaces can meet the needs. However, for powders that need to react with the atmosphere in the furnace, the accumulation of powders often leads to insufficient and uneven reactions, and prolonging the reaction time can also lead to unsatisfactory decomposition for some processes.

[0004] To solve this problem, new heat treatment equipment has been designed and developed, and rotatable tube furnaces have been used in the reaction of metal powders and atmosphere. However, most of the current equipment adopts an integral design. For fine-particle powders below 10μm, due to their poor powder fluidity, it is very easy to cause feeding difficulties, powder stuck in gaps, and uneven heating of the sticking tube wall. These problems not only affect the powder preparation, but also make the furnace difficult to clean and cause pollution. Nowadays, more and more high-performance new materials cannot do without the heat treatment of fine-particle powders. Due to the high activity of fine powders, they are more sensitive to the reaction atmosphere and temperature. For example, the particle size of samarium iron powder prepared by the co-precipitation method is close to 2μm. The nitriding process requires more effective and convenient equipment to enable the stable mass production of high-performance materials. Utility Model Content

[0005] The utility model aims to provide a mixing grinding aid device for heat treatment of metal alloy powder, so as to solve the problems of insufficient reaction and furnace cleaning in the prior art.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] A hybrid grinding aid device suitable for low-temperature heat treatment of metal alloy powders comprises a vacuum system, a rotary transmission system, a fan-shaped furnace pipe, and a minimum material storage unit. The vacuum system is connected to the rotary transmission system through an air guide pipe and a limit sleeve, and the rotary transmission system drives the fan-shaped furnace pipe and the embedded minimum material storage unit to move in a low-speed circular rotation. The minimum material storage unit is internally loaded with a material storage tank body, and the material storage tank body is internally built with a grid baffle, and the upper and lower parts of the grid baffle are both equipped with grinding balls.

[0008] Preferably, the vacuum system can mix and replace the three gases, the dynamic pressure in the furnace does not exceed 0.13 MPa, the pressure sensor monitors the pressure at the air inlet, and the safety valve ensures pressure release.

[0009] Preferably, there is only a strong axial constraint in the connection between the vacuum system and the rotary transmission system. Under the action of the limiting sleeve, the rotary transmission system does not drive the air duct and the vacuum system to move, and the angular velocity of the rotary transmission system does not exceed 8 r / min.

[0010] Preferably, the fan-shaped furnace tube is provided with 4-8 inverted cone-shaped protrusions, and the minimum material storage unit can be assembled with the fan-shaped furnace tube by direct fitting, transition fitting and interference fitting.

[0011] Preferably, the minimum storage unit can be made of aluminum alloy, stainless steel, titanium alloy and other materials according to the temperature requirements. The external accessories can be replaced according to the process pressure to connect the fan furnace tube atmosphere and pressure. A filter can be provided on the connecting path, or a closed system with independent atmosphere and independent pressurization can be set with a pressure not exceeding 2MPa.

[0012] Preferably, the minimum storage unit selects suitable grinding balls and mesh baffle materials according to the powder characteristics, such as stainless steel, zirconia, silicon dioxide, titanium alloy, etc. According to the powder particle size, the grinding ball size range is 5mm-25mm, the ball-to-material ratio is 0-15, the volume does not exceed 1 / 3 of the storage tank body, and is evenly divided into the upper and lower parts of the mesh baffle. The size of the mesh baffle should allow the powder to pass through, but block the grinding balls so that they move irregularly during the rotation of the furnace tube and hit the tank wall and the powder.

[0013] The technical solution of the utility model has the following beneficial effects:

[0014] 1. The fan-shaped furnace tube rotates at a low speed to drive the smallest storage unit to move. With the help of the stirring and grinding effect of the internal grinding balls and mesh baffles, it can effectively increase the contact area between the powder material and the gas or increase the probability of effective contact between the materials, thereby accelerating the reaction process. At the same time, it also avoids problems such as overheating and decomposition caused by local powder stuck on the tube wall and insufficient reaction. Compared with the integral furnace tube, it is easy to clean and replace, which is convenient and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings required for describing the embodiments are briefly introduced below.

[0016] Figure 1 A schematic diagram of a furnace body of an alloy powder heat treatment device designed for the utility model.

[0017] Figure 2The utility model is designed to be a schematic diagram of the internal structure of the minimum material storage unit that can be used for mixing and grinding.

[0018] Figure 3 The utility model is designed for the assembly of the material storage unit and the fan-shaped furnace tube.

[0019] Figure 4 This is a schematic diagram of the external assembly form of the storage unit designed for the utility model.

[0020] Figure 5 Schematic diagram of the furnace vacuum system designed for the utility model.

[0021] Figure numerals: 1. Vacuum system; 2. Air guide duct; 3. Limiting sleeve; 4. Rotating transmission system; 5. Metal shell; 6. Thermal insulation layer; 7. Temperature control system; 8. Fan furnace tube; 9. Exhaust valve; 10. Minimum storage unit; 11. Cooling system; 12. Control power supply cabinet; 13. Storage tank; 14. Grinding balls; 15. Grid baffle. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the utility model and are not used to limit the utility model. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0023] A sample preparation method and device for measuring the high-temperature thermal diffusion coefficient of fibers in a mixing and grinding aid device for heat treatment of metal alloy powders, comprising a vacuum system 1, a rotary transmission system 4, a fan-shaped furnace tube 8, and a minimum storage unit 10. The vacuum system 1 is connected to the rotary transmission system 4 through an air guide duct 2 and a limit sleeve 3, and the rotary transmission system 4 drives the fan-shaped furnace tube 8 and the embedded minimum storage unit 10 to move in a low-speed circular rotation. The minimum storage unit 10 is internally loaded with a storage tank body 13, and the storage tank body 13 has a built-in mesh baffle 15, and the upper and lower parts of the mesh baffle 15 are provided with grinding balls 14.

[0024] refer to Figure 1 The device is composed of a vacuum system 1, a rotary transmission system 3, a temperature control system 7, a fan-shaped furnace tube 8, a minimum material storage unit 10, a cooling system 11, a control power cabinet 12 and other accessories. The cooling system 11 is installed at the tail end of the fan-shaped furnace tube 8, and an exhaust valve 9 is arranged above the cooling system 11. The heat and pressure accumulated inside the fan-shaped furnace tube 8 are dissipated and exhausted through the exhaust valve 9 on the cooling system 11, and the electromagnetic valve controlled by the control power cabinet 12 can be set to control the on and off of the exhaust valve 9.

[0025] Furthermore, a temperature control system 7 is installed on the periphery of the fan-shaped furnace tube 8. The temperature control system senses the ambient temperature through a temperature sensor, the controller makes a judgment and issues a command according to the set temperature range, the actuator adjusts the temperature according to the command, and the feedback loop ensures the stability and accuracy of the system. These components work together to enable the temperature control system to automatically keep the ambient temperature within the set range. The outer wall of the temperature control system 7 is provided with a heat insulation layer 6 in contact with the outside world, which is used to isolate the high temperature generated inside the fan-shaped furnace tube 8 and prevent burns caused by contact on the surface of the equipment, greatly improving the safety performance of the overall equipment.

[0026] Furthermore, the outside of the rotation transmission system 3 is covered with a metal shell 5 , which improves the working environment of the rotation transmission system 3 and prevents dust from entering the inside of the rotation transmission system 3 .

[0027] In the above scheme, under the heat treatment condition of less than 800°C, the fan-shaped furnace tube 8 rotates at a low speed to drive the minimum storage unit 10 to move. With the help of the stirring and grinding effect of the internal grinding balls 14 and the grid baffle 15, the contact area between the powder material and the gas or the probability of effective contact between the materials can be effectively increased, thereby accelerating the reaction process. At the same time, it also avoids problems such as overheating decomposition and insufficient reaction caused by local powder sticking on the tube wall. Compared with the integral furnace tube, it is easy to clean and replace, convenient and efficient.

[0028] Worth noting: Figure 3 In the middle: a, b, and c represent direct engagement, transition engagement, and interference engagement between the minimum material storage unit 10 and the fan tube 8, respectively. Figure 4 In the figure, d indicates that the tank body is connected to the furnace atmosphere; e indicates that the inside of the tank body is closed.

[0029] Embodiment 1:

[0030] The specific steps of heat treatment of SmFeN alloy powder are as follows:

[0031] 1. Two stainless steel storage tanks 13 directly embedded with the fan-shaped furnace tubes 8 are selected, the internal stainless steel mesh baffle 15 has a pore diameter of 3mm, and 500g of 5mm stainless steel grinding balls are evenly distributed on both sides of the baffle.

[0032] Second, 1000 g of samarium-iron alloy powder with a particle size of about 11 μm is added to each storage tank 13, and the external accessories of the storage tank 13 are selected to be connected to the furnace tube atmosphere, and are pushed into the furnace body after assembly.

[0033] 3. After the furnace body is evacuated, a flowing atmosphere is introduced at a ratio of ammonia to hydrogen of 1:2. The furnace tube speed is set to 3r / min. After treating at 450℃ for 3h, argon is introduced to replace the gas in the furnace. Dehydrogenation is carried out at 450℃ for 1h, and then the furnace is cooled to room temperature and ventilation is stopped.

[0034] Fourth, the stainless steel storage tank 13 is taken out by a pull rod, and the grinding balls 14 are separated by a sieve in a nitrogen box to obtain samarium iron nitrogen powder.

[0035] 5. Clean the grinding balls 14 and the grid baffle 15, and check, clean and replace the stainless steel tank accessories of the minimum storage unit 10.

[0036] Embodiment 2:

[0037] The difference between the scheme of Example 3 and Example 1 is that the heat-treated powder is a ferrosilicon alloy flake prepared by a rapid quenching method. The heat treatment steps for preparing the samarium iron nitrogen alloy powder are as follows:

[0038] 1. Select a stainless steel storage tank 13 that is directly embedded with the fan-shaped furnace tube 8, the internal stainless steel grid baffle 15 has a pore size of 3mm, and 1000g of 5mm stainless steel grinding balls and 500g of 15mm stainless steel balls are evenly distributed on both sides of the baffle.

[0039] 2. Add 3000g of samarium-iron alloy flakes into the tank body, and select the external accessories of the storage tank body 13 to be connected with the furnace tube atmosphere, and push them into the furnace body after assembly.

[0040] 3. After the furnace body is vacuumed, a flowing atmosphere is introduced at a ratio of 1:2 between ammonia and hydrogen. The furnace tube speed is set to 3r / min. After treating at 450℃ for 6h, argon is introduced to replace the gas in the furnace. Treat at 450℃ for 1h for dehydrogenation, then cool to room temperature and stop ventilation.

[0041] Fourth, the stainless steel storage tank 13 is taken out by a pull rod, and the grinding balls 14 are separated by a sieve in a nitrogen box to obtain the ground samarium iron nitrogen powder.

[0042] 5. Clean the grinding balls 14 and the grid baffle 15, and check, clean and replace the accessories of the stainless steel storage tank 13 of the minimum storage unit 10.

[0043] Embodiment three:

[0044] In the scheme of Example 3, cobalt, copper, iron and nickel powders are mixed for reduction annealing. In Example 3, a transition-matched iron storage tank 13 is selected, with iron balls and iron mesh baffles built in, which is connected to the hydrogen atmosphere of the furnace tube, and hydrogen reduction is carried out at 550°C for 2h. Steps 1 to 5 in Example 2 are repeated to obtain a proportionally mixed aluminum-nickel-cobalt precursor powder, and the deformed iron storage tank 13 is replaced in time.

[0045] According to the present invention, the contact area between the powder material and the gas can be effectively increased or the probability of effective contact between the materials can be increased, thereby accelerating the reaction process, while also avoiding problems such as overheating and decomposition caused by local powder stuck on the tube wall and insufficient reaction. Compared with the integral furnace tube, it is easy to clean and replace, convenient and efficient. It can enable small batches of high-performance powders that are highly sensitive to atmosphere, temperature uniformity, and pressure to be stably produced.

[0046] The above embodiments are only exemplary embodiments of the present invention and are not intended to limit the present invention. The protection scope of the present invention is defined by the claims. Various modifications or equivalent substitutions may be made to the present invention within the essence and protection scope of the present invention. Such modifications or equivalent substitutions shall also be deemed to fall within the protection scope of the present invention.

[0047] In the description of the present utility model, it should be noted that the terms "inside", "front", "back", "left", "right" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the attached circles, or the directions or positional relationships in which the utility model product is usually placed when in use, and are only used to facilitate the description of the present utility model and simplify the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, these terms indicating directions or positional relationships cannot be understood as limiting the present utility model.

[0048] In the description of the present invention, it is further explained that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense. For example, these terms can indicate a fixed connection, a detachable connection, or an integral connection between elements; they can also indicate a mechanical connection, an electrical connection; they can also indicate a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of these terms in the present invention can be understood according to specific circumstances.

Claims

1. A mixing grinding aid device for heat treatment of metal alloy powder, characterized in that: The invention comprises a vacuum system (1), a rotary transmission system (4), a fan-shaped furnace tube (8), and a minimum material storage unit (10). The vacuum system (1) is connected to the rotary transmission system (4) through an air guide pipe (2) and a limit sleeve (3). The rotary transmission system (4) drives the fan-shaped furnace tube (8) and the embedded minimum material storage unit (10) to move by low-speed circular rotation.

2. A mixing and grinding aid device for heat treatment of metal alloy powder according to claim 1, characterized in that: The minimum material storage unit (10) is internally loaded with a material storage tank (13), the material storage tank (13) is internally provided with a grid baffle (15), and both the upper and lower parts of the grid baffle (15) assist in grinding the grinding balls (14).

3. The mixing and grinding aid device for heat treatment of metal alloy powder according to claim 1, characterized in that: The vacuum system (1) can perform mixing and replacement of multiple gases, and monitoring and release of dynamic pressure.

4. The mixing and grinding aid device for heat treatment of metal alloy powder according to claim 1, characterized in that: There is only a strong axial constraint in the connection between the vacuum system (1) and the rotary transmission system (4); under the action of the limiting sleeve (3), the rotary transmission system (4) does not drive the air guide pipe (2) and the vacuum system (1) to move.

5. The mixing and grinding aid device for heat treatment of metal alloy powder according to claim 1, characterized in that: The fan-shaped furnace tube (8) is provided with a plurality of inverted cone-shaped protrusions, and the minimum material storage unit (10) can be engaged with the fan-shaped furnace tube (8) in a variety of forms.

6. The mixing and grinding aid device for heat treatment of metal alloy powder according to claim 2, characterized in that: The minimum material storage unit (10) can replace the material storage tank (13) according to the temperature requirements, and can replace the external accessories to connect with the fan-shaped furnace tube (8) or increase the internal pressure according to the process pressure.

7. The mixing and grinding aid device for heat treatment of metal alloy powder according to claim 2, characterized in that: The minimum material storage unit (10) can replace internal grinding balls (14) and grid baffles (15) according to material properties and requirements.

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