An atmosphere-controllable high-temperature ball mill

Abstract

The present application belongs to the technical field of powder material ball milling equipment, and particularly relates to a high-temperature ball mill capable of adjusting atmosphere, comprising: a furnace body and a rotatable furnace pipe arranged in the furnace body, a heating element for heating the furnace pipe is arranged in the furnace body, both ends of the furnace pipe extend to the outside of the furnace body and are connected with a rotary driving device, one end of the furnace pipe is sealed, and the other end is connected with a target atmosphere pipeline; a ball mill tank is arranged in the furnace pipe and is slidably inserted along the axial direction of the furnace pipe, the inside of the ball mill tank is pre-filled with a target gas or is vacuumized; a limiting rod is fixedly arranged in the furnace cover away from the protective atmosphere pipeline end of the furnace pipe, a plurality of limiting blocks are fixedly arranged on the inner wall of the furnace pipe close to the other end of the furnace pipe and located in the constant-temperature zone of the furnace body. Since no rubber sealing element is arranged in the ball mill tank itself, the ball mill tank can withstand a higher heating temperature in the target atmosphere environment, and the ball milling process requirements of a wide temperature range from room temperature to 1700 DEG C and adjustable atmosphere are realized.

Description

Technical Field

[0001] This invention belongs to the technical field of ball milling equipment for powder materials, and specifically relates to a high-temperature ball mill with adjustable atmosphere. Background Technology

[0002] Powder materials, due to their unique physicochemical properties, have wide applications in energy, electronics, ceramics, catalysts, and composite materials. Traditional powder preparation methods include mechanical ball milling, chemical precipitation, and sol-gel methods. Among these, mechanical ball milling is a powder preparation technology that uses high-energy mechanical force to break down, refine, and alloy solid materials. This method utilizes the collision, shearing, and friction between the grinding balls and the material to continuously break, cold-weld, and reassemble particles, ultimately obtaining micron- or nano-sized powders. Due to its simple process, low cost, and scalability, mechanical ball milling is widely used in the preparation of metals, ceramics, composite materials, and functional materials.

[0003] Currently, common ball milling equipment, categorized by drive type, mainly includes planetary ball mills, vibratory ball mills, and drum ball mills. To improve milling efficiency, high-temperature ball mills are commonly used. However, for certain chemically highly reactive metal element powders, which typically have small particle sizes and large specific surface areas, they readily undergo oxidation reactions with residual oxygen in the air during ball milling, generating metal oxide impurities. This phenomenon is particularly pronounced during prolonged ball milling, ultimately leading to a decrease in the purity of the resulting metal powder and severely impacting the final performance of the material.

[0004] However, existing high-temperature ball mills generally introduce the protective atmosphere directly into the inside of the grinding jar. This means that when the ball mill operates at high temperatures, the excessively high temperature will affect the sealing performance of the rubber sealing structure inside the grinding jar. In severe cases, it may even melt the rubber sealing structure, causing the protective atmosphere inside the grinding jar to leak. As a result, existing ball mills cannot meet the sealing requirements for the protective atmosphere at high temperatures. Summary of the Invention

[0005] To address the aforementioned technical problems, the present invention aims to provide a ball mill that can simultaneously meet the requirements of high temperature and protective atmosphere operating conditions, thereby improving the operating temperature of the ball mill under protective atmosphere conditions.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A high-temperature ball mill with adjustable atmosphere includes: a furnace body and a rotatable furnace tube disposed within the furnace body. The furnace body is equipped with heating elements for heating the furnace tube. Both ends of the furnace tube extend to the outside of the furnace body and are connected to a rotary drive device for driving the furnace tube to rotate. One end of the furnace tube is mechanically sealed, and the other end of the furnace tube is connected to a target atmosphere pipeline for connecting the furnace tube to an external gas source or a vacuum device. A ball milling jar is slidably inserted into the furnace tube along its axial direction. The ball milling jar is used for ball milling materials and is pre-filled with a target gas or evacuated. A limiting rod is fixedly installed on the furnace cover at the end of the furnace tube away from the protective atmosphere pipeline, and multiple limiting blocks are fixedly installed circumferentially on the inner wall of the furnace tube near the other end of the furnace tube in the constant temperature zone of the furnace body.

[0008] Furthermore, multiple grooves are coaxially arranged on the outer walls of the end cap and base of the ball mill jar, and multiple positioning blocks that are inserted into and cooperate with the grooves are correspondingly provided on the inner wall of the furnace tube.

[0009] Furthermore, the rotary drive device includes a support, a motor, and a transmission mechanism. The two ends of the furnace tube are rotatably mounted on the support, and the motor is connected to the furnace tube through the transmission mechanism to drive the furnace tube to rotate.

[0010] Furthermore, the transmission mechanism is a belt drive mechanism or a chain drive mechanism;

[0011] Furthermore, the target atmosphere pipeline includes an inlet and outlet pipe, one end of which is connected to the end of the furnace tube via a rotary sealing joint, and the other end of which is used to connect to an external gas source or a vacuum device. The inlet and outlet pipe is equipped with a switch control valve.

[0012] Furthermore, the switch-controlled valve is equipped with a flow detector;

[0013] Furthermore, the limiting block is a perforated plate;

[0014] Furthermore, the furnace tube contains multiple ductile iron containers;

[0015] Furthermore, the ball milling temperature of the high-temperature ball mill is between room temperature and 1700°C.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] This invention ensures that the ball milling process takes place under the target atmosphere by injecting a target gas into the milling jar before ball milling, essentially filling it with the target gas atmosphere. The jar is then placed in a rotating furnace tube, and the target atmosphere is introduced into the furnace tube. Since the milling jar itself does not use rubber seals, the target gas filling the furnace tube can slowly seep into the jar, allowing the jar to withstand higher heating temperatures within the target atmosphere. This method ingeniously solves the current technical challenge of achieving high-temperature sealing, successfully meeting the requirements of ball milling processes with a wide temperature range from room temperature to 1700°C and adjustable atmosphere. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of a high-temperature ball mill with adjustable atmosphere according to the present invention.

[0019] In the diagram: 1. Furnace body; 2. Inner wall; 3. Grinding jar; 4. Limiting block; 5. Transmission mechanism; 6. Furnace tube; 7. Rotary sealing joint; 8. Switch control valve; 9. Inlet and outlet gas pipes; 10. Motor; 11. Bracket; 12. Pulley; 13. Limiting rod; 14. Flange connector. Detailed Implementation

[0020] The technical solutions adopted in this invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0021] First, this invention provides a high-temperature ball mill with adjustable atmosphere, the overall structure of which is as follows: Figure 1 As shown, it includes: a heating device, a furnace tube 6, a ball mill jar 3, a rotary drive device, and a target atmosphere pipeline, wherein:

[0022] The heating device serves as the heating mechanism for the entire high-temperature ball mill. Specifically, the heating device can be an existing rotary kiln or tube furnace. In this embodiment, it includes a furnace body 1, which is equipped with a heating element for heating the furnace chamber. The furnace chamber is equipped with a rotatable furnace tube 6, which can be heated by controlling the heating element. The ball milling temperature of the high-temperature ball mill is between room temperature and 1700°C.

[0023] The ball mill jar 3 is used for ball milling of materials. It is slidably disposed inside the furnace tube 6 along the axial direction of the furnace tube 6. The present invention utilizes the heated furnace tube 6 to further heat the ball mill jar 3 to achieve ball milling at high temperature. At the same time, in order to meet the need for the ball mill jar 3 to rotate during ball milling, the present invention sets the outer wall of the ball mill jar 3 and the inner wall 2 of the furnace tube 6 to be in an insert fit. That is, the ball mill jar 3 can be slidably disposed inside the furnace tube 6 along the axis of the furnace tube 6. By utilizing the insert fit between the outer wall of the ball mill jar 3 and the inner wall 2 of the furnace tube 6, the ball mill jar 3 can be rotated synchronously when the furnace tube 6 rotates.

[0024] Specifically, multiple grooves can be coaxially arranged on the outer walls of the end cap and base of the ball mill jar 3, and each groove is arranged along the axial direction of the ball mill jar 3; at the same time, multiple positioning blocks that match the grooves are arranged circumferentially on the inner wall 2 of the furnace tube 6. The multiple positioning blocks can be inserted into the grooves by sliding the ball mill jar 3 in the furnace tube 6. In this way, when the furnace tube 6 rotates, the ball mill jar 3 can be rotated together by the insertion and cooperation of the positioning blocks and the grooves. Alternatively, the opposite arrangement can be adopted to achieve ball milling of the material in the ball mill jar 3.

[0025] Furthermore, the present invention also provides a positioning structure inside the furnace tube 6 to limit the ability of the ball mill jar 3 to move along the axial direction of the furnace tube 6 inside the furnace tube 6, and to ensure that the ball mill jar 3 can be in the constant temperature zone of the furnace, thereby ensuring the heating efficiency of the ball mill jar 3.

[0026] Specifically, the positioning structure includes: a limiting rod 13 fixedly installed in the furnace cover at one end of the furnace tube 6 away from the protective atmosphere pipeline, and a plurality of limiting blocks 4 fixedly installed on the inner wall 2 of the furnace tube 6 in the constant temperature zone, near the other end of the furnace tube 6. The plurality of limiting blocks 4 are arranged along the circumference of the inner wall 2, and their shape is preferably a perforated plate to facilitate the flow of the protective atmosphere in the furnace tube 6.

[0027] Specifically, the ball milling jar 3 is confined within the constant temperature zone of the furnace chamber by the limiting rod 13 and the limiting block 4, which are respectively arranged opposite to each other inside the furnace tube 6. At the same time, the limiting rod 13 can also be fixedly connected to the end of the ball milling jar 3, so as to push the ball milling jar 3 inside the furnace tube 6 until the ball milling jar 3 abuts against the limiting block 4 and to pull the ball milling jar 3 out of the furnace tube 6 after the ball milling process is completed. Alternatively, a wheel mechanism can be installed on the furnace cover at the end of the furnace tube 6. Through the meshing transmission of the limiting rod 13 and the precision groove of the end cover of the ball milling jar 3 of the corresponding size, the ball milling jar 3 and the furnace tube 6 can be ensured to rotate synchronously.

[0028] In addition, as a preferred technical solution, multiple ball mill jars 3 can be connected end to end in sequence through connecting flanges to form a whole, and then simultaneously installed in the furnace tube 6 in the same manner as described above, so as to realize the simultaneous ball milling of different types of materials.

[0029] Furthermore, both ends of the furnace tube 6 extend to the outside of the furnace body 1 so that the furnace tube 6 can be connected to the rotary drive device to realize the rotation of the furnace tube 6 in the furnace chamber. In this embodiment, the rotary drive device includes: a bracket 11, a motor 10 and a transmission mechanism 5.

[0030] Specifically, the two ends of the furnace tube 6 are rotatably mounted on the support 11. In this embodiment, a receiving part composed of multiple rotatable pulleys 12 can be provided at both ends of the support 11. The shape of the receiving part matches the outer wall of the end of the furnace tube 6. The multiple pulleys 12 are distributed circumferentially along the outer wall of the furnace tube 6. Then, the two ends of the furnace tube 6 are respectively attached to the receiving part of the support 11 to realize the rotation of the furnace tube 6 on the support 11.

[0031] The motor 10 is connected to the furnace tube 6 through the transmission mechanism 5 to drive the furnace tube 6 to rotate. In this embodiment, the transmission mechanism 5 can be in the form of belt drive or transmission chain. That is, the output shaft of the motor 10 is fixedly connected to the driving wheel, and then the furnace tube 6 is driven to rotate through the transmission belt or transmission chain in conjunction with the driven wheel fixed to the outer wall of the furnace tube 6.

[0032] The end of the furnace tube 6 extending to the outside of the furnace body 1 is also connected to the target atmosphere pipeline. That is, the furnace tube 6 is connected to different target gas sources outside the device, such as protective atmosphere or reducing atmosphere, through the target atmosphere pipeline. It can also be connected to a vacuum pump to fill the furnace tube 6 with the target atmosphere or to evacuate it.

[0033] Specifically, one end of the furnace tube 6 uses a mechanical seal with a flange connector 14 and a high-temperature resistant rubber sealing ring, while the other end is connected to the inlet and outlet gas pipes 9 via a rotary sealing joint 7, such as a self-tightening graphite sealing ring. The inlet and outlet gas pipes 9 are also equipped with a switch control valve 8. By connecting the inlet and outlet gas pipes 9 to different gas sources or vacuum pumps outside the device, different protective atmospheres are introduced into the rotating furnace tube 6 through the rotary sealing joint 7 via the switch control valve 8, so that the ball milling jar 3 works under a protective atmosphere. In specific use, before ball milling, the target gas is first injected into the ball milling jar 3 to make the ball milling jar 3 basically full of the target gas atmosphere. Then, the ball milling jar 3 is placed in the furnace tube 6, and the target atmosphere is introduced into the furnace tube 6 through the target atmosphere pipeline, thereby ensuring that the ball milling process is carried out under the target atmosphere.

[0034] Since the ball mill jar 3 itself does not use rubber seals, the target gas filling the furnace tube 6 can slowly seep into the ball mill jar 3, enabling the ball mill jar 3 to withstand higher heating temperatures in the target atmosphere environment, thus meeting the process requirements of ball milling under both high temperature and target atmosphere conditions. Similarly, by connecting the inlet and outlet gas pipes 9 to the vacuum device, the process requirements under high temperature and vacuum conditions can be met.

[0035] The materials of the grinding jar 3 and the grinding balls can be adapted and adjusted according to the grinding temperature: stainless steel is used for temperatures of 800℃ and below, zirconium oxide is used for 800~1200℃, and high-strength special ceramic is used for temperatures above 1200℃, so as to meet the requirements of different temperature ranges for the heat resistance, mechanical strength and chemical stability of the materials.

[0036] In addition, as a preferred technical solution, a flow detector can be installed on the switch control valve 8 to monitor the protective atmosphere entering the furnace tube 6, so as to accurately control the protective atmosphere entering the furnace tube 6 and meet the process requirements of different material preparation.

[0037] The following examples illustrate the use of the ball mill provided by this invention, using MOF materials as the synthesis object for ball milling.

[0038] Example 1:

[0039] The specific operating steps are as follows: First, the metal salt and organic ligand are mixed in a certain proportion, and then the mixture is loaded into the grinding jar 3 along with stainless steel grinding balls in a certain proportion. The end cap of the grinding jar 3 is fixed with flanges and bolts. Then, the assembled grinding jar 3 is pushed in axially along the furnace tube 6, so that the groove and the positioning block are precisely aligned, until the right side of the grinding jar 3 contacts the limiting block 4 of the constant temperature zone. Next, the flange connector 14 of the furnace cover on the left side of the furnace tube 6 is fixed. At this time, the right end of the limiting rod 13 is precisely positioned on the left side of the constant temperature zone, thus ensuring that the grinding jar 3 is stably in the center of the constant temperature zone. The heating device is started, and resistance wire heating is used to raise the temperature to the target range of 50-200℃ at a heating rate of 5-8℃ / min. At the same time, the furnace tube 6 is rotated by the transmission mechanism 5 driven by the motor 10. After maintaining the constant temperature reaction for 5-10 hours, a series of MOF material products with regular morphology and excellent performance are finally obtained, with a stable yield of 70-80%.

[0040] Example 2: In this embodiment, a high-temperature alloy material is used as the synthesis object, and the specific operation steps are the same as in Embodiment 1.

[0041] The difference lies in the fact that, during the synthesis of the high-temperature alloy material, the grinding jar 3 and the grinding balls need to be replaced with zirconium oxide. After the material is loaded and the grinding jar 3 is "gas-filled" and sealed, the internal air is replaced by vacuuming or introducing protective gas to establish the required reaction atmosphere. The heating device uses a silicon carbide rod heating system, raising the temperature to the target range of 800-1700℃ at a heating rate of 5-10℃ / min, and maintaining the reaction at this temperature for 5-10 hours to finally obtain a high-temperature alloy material with excellent comprehensive properties.

[0042] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the technical scope of the present invention. Therefore, any minor modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A high-temperature ball mill with adjustable atmosphere, comprising: The furnace body (1) and the furnace tube (6) rotatably disposed in the furnace body (1) are provided with heating elements for heating the furnace tube (6). The two ends of the furnace tube (6) extend to the outside of the furnace body (1) and are connected to a rotary drive device. The rotary drive device is used to drive the furnace tube (6) to rotate. One end of the furnace tube (6) is mechanically sealed. The other end of the furnace tube (6) is connected to a target atmosphere pipeline. The target atmosphere pipeline is used to connect the furnace tube (6) to an external gas source or a vacuum device. The feature is that a ball milling jar (3) is slidably inserted into the furnace tube (6) along the axial direction of the furnace tube (6), and the ball milling jar (3) is used to ball mill the material, and its interior is pre-filled with target gas or evacuated; A limiting rod (13) is fixedly installed inside the furnace cover at the end of the furnace tube (6) away from the protective atmosphere pipeline, close to the other end of the furnace tube (6), and located on the inner wall (2) of the furnace tube (6) in the constant temperature zone of the furnace body (1). Multiple limiting blocks (4) are fixedly installed circumferentially. The ball mill jar (3) itself does not use rubber seals.

2. The high-temperature ball mill with adjustable atmosphere according to claim 1, characterized in that, Multiple grooves are coaxially arranged on the outer wall of the end cap and base of the ball mill jar (3), and multiple positioning blocks that are inserted into and cooperate with the grooves are correspondingly arranged on the inner wall (2) of the furnace tube (6).

3. The high-temperature ball mill with adjustable atmosphere according to claim 1, characterized in that, The rotary drive device includes a bracket (11), a motor (10) and a transmission mechanism (5). The two ends of the furnace tube (6) are rotatably mounted on the bracket (11). The motor (10) is connected to the furnace tube (6) through the transmission mechanism (5) to drive the furnace tube (6) to rotate.

4. A high-temperature ball mill with adjustable atmosphere according to claim 3, characterized in that, The transmission mechanism (5) is a belt drive mechanism or a chain drive mechanism.

5. A high-temperature ball mill with adjustable atmosphere according to claim 1, characterized in that, The protective atmosphere pipeline includes: an inlet and outlet gas pipe (9), one end of which is connected to the end of the furnace tube (6) through a rotary sealing joint (7), and the other end of which is used to connect to an external gas source or a vacuum device. The inlet and outlet gas pipe (9) is equipped with a switch control valve (8).

6. A high-temperature ball mill with adjustable atmosphere according to claim 5, characterized in that, The switch control valve (8) is equipped with a flow detector.

7. A high-temperature ball mill with adjustable atmosphere according to claim 1, characterized in that, The limiting block (4) is a perforated plate.

8. A high-temperature ball mill with adjustable atmosphere according to claim 1, characterized in that, Multiple ball milling jars (3) are provided inside the furnace tube (6), and the multiple ball milling jars (3) are fixedly connected in sequence inside the furnace tube (6).

9. A high-temperature ball mill with adjustable atmosphere according to claim 1, characterized in that, The ball milling temperature of the high-temperature ball mill is between room temperature and 1700°C.

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