A vacuum heating device

Abstract

The present invention discloses a vacuum heating device, including a sample chamber, a heating system and a vacuum pump for evacuating the sample chamber, wherein a placement for placing a sample is provided in the sample chamber, and a plurality of layers of oxygen absorption sources are provided around the placement, and the plurality of layers of oxygen absorption sources are connected by a connector, and the connector is detachably connected to the sample chamber, and the heating system is used to heat the sample and the oxygen absorption source respectively; the connector is a connecting plate with a groove or a plurality of connecting blocks with through holes. The vacuum heating device disclosed by the present invention has a plurality of layers of oxygen absorption sources provided around the sample placement in the sample chamber, and the oxygen absorption sources react with free oxygen in the heating state, thereby slowing down or preventing the sample from being oxidized during high-temperature heat treatment, and the oxygen absorption sources and the vacuum pump work together to reduce the oxygen molecule content in the sample chamber, and under this structure, in order to prevent the sample from being oxidized, the pressure in the sample chamber can be less than 10pa.

Description

Technical Field

[0001] The invention relates to the field of vacuum heating, in particular to a vacuum heating device. Background Art

[0002] The vacuum heating device is mainly composed of vacuum pump, furnace body, heating body and pipelines. There are many types, including vacuum heat treatment furnace, vacuum brazing furnace and heating vapor deposition device. In order to avoid oxidation of samples by reaction with oxygen molecules at high temperature, most vacuum heating devices usually require the vacuum degree in the heating device to be better than 10 before starting heating. - 3 Pa, such as vacuum welding furnace, vacuum heat treatment furnace and thermal evaporation device.

[0003] The source of oxygen molecules in the heating device is mainly the release of oxygen adsorbed on the inner surface of the equipment and the overflow of air in the environment. Therefore, the sealing performance of the device and pipelines and the pumping rate and stability of the vacuum system are important factors affecting the vacuum degree of the device. The former has high requirements on material properties and processing accuracy, while the latter is directly related to the type, performance and reliability of the vacuum pump. Although the market is capable of widely supplying high vacuum heating devices, it has high requirements on vacuum pumping time and equipment maintenance costs, and is often accompanied by high purchase and maintenance costs.

[0004] In the prior art, a Chinese patent with publication number CN114045468A discloses a thin film deposition device, a physical vapor deposition apparatus and a thin film deposition method, wherein the disclosed thin film deposition device includes a thin film deposition chamber for providing a thin film deposition environment, a sample holder for fixing a substrate and capable of achieving X, Y, and Z three-dimensional movement, 360-degree continuous rotation and angle adjustment, a plurality of deposition modules for depositing a thin film on the substrate and capable of retracting and adjusting the angle, a feedback module for monitoring the growth process and state of the thin film, and a control module for receiving feedback information from the feedback module and controlling the deposition module and / or the sample holder according to the feedback information.

[0005] There is also a physical vapor deposition sample heating device in the prior art, such as the Chinese patent with publication number CN210367896U, which includes a heating element working in a closed cavity and a sample loading mechanism for carrying the sample. The heating element is a silicon carbide heating plate, and the heating element includes a silicon carbide plate, a heating resistance wire arranged in the silicon carbide plate, and a ceramic terminal connected to the resistance wire. The sample loading mechanism is distributed on one side or both sides of the silicon carbide heating plate.

[0006] Although the thin film deposition equipment provided by the above two patents can also achieve vacuum in the cavity, the former has a complex structure and is difficult to operate, and the oxygen content inside the cavity of both is only related to the vacuum degree in the cavity. Therefore, the vacuum degree of the cavity is extremely high, and the problem of high requirements for the equipment in terms of vacuum time and equipment maintenance costs is not solved. Summary of the invention

[0007] In order to solve the problems existing in the prior art, the present invention provides a vacuum heating device.

[0008] A vacuum heating device comprises a sample chamber, a heating system and a vacuum pump for evacuating the sample chamber, wherein a placement area for placing a sample is provided in the sample chamber, a plurality of layers of oxygen absorption sources are provided around the placement area, the plurality of layers of oxygen absorption sources are connected by a connecting piece, the connecting piece is detachably connected to the sample chamber, the heating system is used to heat the sample and the oxygen absorption source respectively; the connecting piece is a connecting plate with a groove or a plurality of connecting blocks with through holes.

[0009] Specifically, since the sample is arranged inside the sample chamber, the oxygen absorption source arranged around the sample is arranged near the inner wall of the sample chamber, near the sample, and at the joints of structural components prone to air leakage; the heating system can provide independent and controllable heating for the sample and the oxygen absorption source respectively; the heating methods of the heating system include resistance heating, induction heating, laser heating and external heat transfer; the number of layers of oxygen absorption sources is at least 1, preferably, the number of layers is 1-50, more preferably, 1-20, and most preferably, 1-10.

[0010] Preferably, the vacuum heating device also includes an atmosphere regulating device, which includes a gas source storing inert gas or reducing gas, a connecting pipeline connecting the gas source and the sample chamber, a gas flow meter, and a valve for controlling the gas source switch.

[0011] Specifically, when the sample chamber is in a negative pressure state, the valve of the gas source is opened, and the gas source injects inert gas or reducing gas into the sample chamber. The atmosphere adjustment device cooperates with the oxygen absorption source and the vacuum pump to reduce the oxygen content in the sample chamber.

[0012] Preferably, the oxygen absorption source is made of an easily oxidizable metal material.

[0013] Specifically, one or more of magnesium, titanium, aluminum, tantalum, chromium, iron, silver, and copper are selected; the oxygen fixation effect of the oxygen absorption source is related to many factors such as the material's ability to react with oxygen at a certain temperature, the contact area with oxygen reaction, and the material thickness. In comparison, the stronger the material's ability to react with oxygen, the higher the oxygen absorption efficiency of the oxygen absorption source. Therefore, it is appropriate to select one or more of magnesium, titanium, aluminum, tantalum, chromium, iron, silver, and copper; in addition, the larger the contact area between the oxygen absorption source and the oxygen reaction, the higher the oxygen absorption efficiency of the oxygen absorption source; the larger the material thickness, particle diameter, or wire diameter, the longer the durable life of the oxygen absorption source;

[0014] At the same time, the operating temperature of the oxygen absorption source should be lower than its melting point. Preferably, the operating temperature of the oxygen absorption source is at least 50°C lower than its melting point. More preferably, the operating temperature of the oxygen absorption source is at least 100°C lower than its melting point.

[0015] Preferably, the oxygen absorption source includes a substrate and an oxygen absorption layer coated on the substrate, the oxygen absorption layer is made of an easily oxidizable metal material; the oxygen absorption layer is a composite coating of at least two layers, the outermost layer of the composite coating is a protective layer, and the protective layer is made of a metal that is easy to form a dense oxide film.

[0016] Specifically, the protective layer is made of any one or more of aluminum, chromium, titanium, silver, copper, and magnesium; and the thickness of the protective layer is less than 1 um.

[0017] Preferably, the oxygen absorbing layer is coated by electroplating, chemical plating or vapor deposition.

[0018] Specifically, the vapor deposition includes chemical vapor deposition and physical vapor deposition.

[0019] Preferably, the oxygen absorption source is in any one or more of the following forms: filamentous, flake-like, foamy, block-like, and granular.

[0020] Specifically, when the vacuum heating device of the present invention is used with high vacuum (pressure less than 10 -3 When the high vacuum device is connected to the sample chamber, the sample chamber is provided with an inlet cover and an outlet cover, and the outlet cover is the entrance of the high vacuum device. At this time, the oxygen absorption source is usually a thin sheet oxygen absorption source, which is bent into a "П" shape, and the sample is arranged inside the "П" shape. The multi-layer oxygen absorption source bent into the "П" shape is fixed in the sample chamber through a connecting block provided with a through hole, and the oxygen absorption source close to the sample is located inside the oxygen absorption source far away from the sample; this structure enables the sample to quickly enter the high vacuum device and avoids a significant oxygen content impact on the atmosphere in the cavity of the high vacuum device;

[0021] When the vacuum heating device of the present scheme is used for heat treatment of samples, a filamentous, foamy, block-shaped or granular oxygen absorption source is arranged in the groove of the connecting plate, and the connecting plate is detachably connected to the sample chamber. At this time, the groove of the connecting plate is not only provided with an oxygen absorption source but also with a fusible salt and is also clamped with a chamber cover or a protective cover, and the sample is arranged on the connecting plate on the inner side of the chamber cover; at the same time, a resistance heating method with a heating rate of 0-30℃ / min is adopted, and the heating range is 0-2000℃, among which it is above 800℃.

[0022] Preferably, the heat treatment is a treatment method for small samples in a negative pressure heating scenario, including welding, annealing and chemical heat treatment.

[0023] Preferably, the particle size range of the granular oxygen absorption source is 100 nm-1 mm.

[0024] Preferably, the particle size of the granular oxygen absorption source is in the range of 1 μm to 500 μm, and more preferably, the particle size of the granular oxygen absorption source is in the range of 10 μm to 200 μm.

[0025] Compared with the prior art, the present invention is beneficial in that:

[0026] Several layers of oxygen absorption sources are arranged around the sample placement in the sample chamber. The oxygen absorption sources react with free oxygen under heating, thereby slowing down or preventing the sample from being oxidized during high-temperature heat treatment. The oxygen absorption sources and the vacuum pump work together to reduce the oxygen molecule content in the sample chamber. Under this structure, in order to prevent the sample from being oxidized, the pressure in the sample chamber can be less than 10Pa. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram of the overall structure of the vacuum heating device provided by the present invention;

[0028] Figure 2 A schematic diagram of the connection structure between the vacuum heating device and the high vacuum device provided by the present invention;

[0029] Figure 3 A schematic diagram of the structure of a connecting plate of a vacuum heating device provided by the present invention;

[0030] Figure 4 This is a schematic structural diagram of the vacuum heating device provided by the present invention when used for heat treatment. DETAILED DESCRIPTION

[0031] The invention will be further described below in conjunction with the accompanying drawings and specific implementation methods.

[0032] like Figure 1As shown, the vacuum heating device comprises a sample chamber 10, a heating system and a vacuum pump for evacuating the sample chamber 10, wherein a placement place 11 for placing a sample is provided in the sample chamber 10, and a plurality of layers of oxygen absorption sources 20 are provided around the placement place 11, and the plurality of layers of oxygen absorption sources 20 are connected by a connecting piece, and the connecting piece is detachably connected to the sample chamber 10, and the heating system is used to heat the sample and the oxygen absorption source 20 respectively;

[0033] like Figure 3 As shown, the connecting member is a connecting plate 32 with a groove 61 or a plurality of connecting blocks 31 with through holes.

[0034] Since the sample is arranged at the placement 11 inside the sample chamber 10, the oxygen absorption source 20 arranged around the sample is arranged at positions including near the inner wall of the sample chamber 10, near the sample, and at the joints of structural components prone to air leakage; the heating system can provide independent and controllable heating for the sample and the oxygen absorption source 20 respectively; the heating methods of the heating system include resistance heating, induction heating, laser heating and external heat transfer; the oxygen absorption source 20 is arranged in at least 1 layer, preferably, the number of layers is 1-50 layers, more preferably, 1-20 layers, and most preferably, 1-10 layers.

[0035] The vacuum heating device also includes an atmosphere regulating device, which includes a gas source 41 storing an inert gas or a reducing gas, a connecting pipe 42 connecting the gas source 41 and the sample chamber 10 , a gas flow meter 44 , and a valve 43 for controlling the switch of the gas source 41 .

[0036] When the sample chamber 10 is in a negative pressure state, the valve 43 of the gas source 41 is opened, and the gas source 41 injects an inert gas or a reducing gas into the sample chamber 10. When the sample chamber 10 is filled with an inert gas or a reducing gas, it is difficult for external air to overflow into the sample chamber 10. The atmosphere adjustment device cooperates with the oxygen absorption source 20 and the vacuum pump to reduce the oxygen content in the sample chamber 10.

[0037] The oxygen absorption source 20 is made of an easily oxidizable metal material.

[0038] One or more of magnesium, titanium, aluminum, tantalum, chromium, iron, silver, and copper are selected; the oxygen fixation effect of the oxygen absorption source 20 is related to many factors such as the ability of the material to react with oxygen at a certain temperature, the contact area with oxygen reaction, and the thickness of the material. In comparison, the stronger the ability of the material to react with oxygen, the higher the oxygen absorption efficiency of the oxygen absorption source 20 is. Therefore, it is appropriate to select one or more of magnesium, titanium, aluminum, tantalum, chromium, iron, silver, and copper; in addition, the larger the contact area of ​​the oxygen absorption source 20 with oxygen reaction, the higher the oxygen absorption efficiency of the oxygen absorption source 20; the larger the material thickness, particle diameter, or wire diameter, the longer the durable life of the oxygen absorption source 20;

[0039] At the same time, the operating temperature of the oxygen absorption source 20 should be lower than its melting point. Preferably, the operating temperature of the oxygen absorption source 20 is at least 50°C lower than its melting point. More preferably, the operating temperature of the oxygen absorption source 20 is at least 100°C lower than its melting point.

[0040] The oxygen absorption source 20 includes a substrate and an oxygen absorption layer coated on the substrate, wherein the oxygen absorption layer is made of an easily oxidizable metal material.

[0041] The oxygen absorption layer is a composite coating layer of at least two layers, the outermost layer of the composite coating layer is a protective layer, and the protective layer is made of a metal that is easy to form a dense oxide film.

[0042] The protective layer is made of any one or more of aluminum, chromium, titanium, silver, copper, and magnesium; and the thickness of the protective layer is less than 1um.

[0043] The oxygen absorption layer is coated by electroplating, chemical plating or vapor deposition.

[0044] The vapor deposition includes chemical vapor deposition and physical vapor deposition.

[0045] The oxygen absorption source 20 is in any one or more of the following forms: filamentous, flake-like, foamy, block-like, and granular.

[0046] like Figure 2 As shown, when the vacuum heating device of this embodiment is used with high vacuum (pressure less than 10 -3 When the high vacuum device 50 is connected, the sample chamber 10 is provided with a chamber inlet cover 12 and a chamber outlet cover 13, and the chamber outlet cover 13 is the entrance of the high vacuum device 50. At this time, the oxygen absorption source 20 is usually a thin sheet oxygen absorption source 20, which is bent into a "П" shape, and the sample is arranged inside the "П" shape. The multi-layer oxygen absorption source 20 bent into the "П" shape is fixed in the sample chamber 10 through a connecting block 31 with a through hole, and the oxygen absorption source 20 close to the sample is located on the inner side of the oxygen absorption source 20 far away from the sample; this structure allows the sample to quickly enter the high vacuum device 50 and avoids a significant oxygen content impact on the atmosphere in the cavity of the high vacuum device 50;

[0047] like Figure 4As shown, when the vacuum heating device of this embodiment is used for heat treatment, the oxygen absorption source 20 in the form of filaments, foam, blocks or particles is arranged in the groove 61 of the connecting plate 32, and the connecting plate 32 is detachably connected to the sample chamber 10. At this time, the groove 61 of the connecting plate 32 is not only provided with the oxygen absorption source 20 but also with a fusible salt, and is also clamped with a chamber cover 62 or a protective cover 63, and the sample is arranged on the connecting plate 32 on the inner side of the chamber cover 62; at the same time, a resistance heating method with a heating rate of 0-30°C / min is adopted, and the heating range is 0-2000°C, wherein the temperature is above 800°C.

[0048] The particle size of the granular oxygen absorption source 20 is in the range of 100 nm to 1 mm.

[0049] Preferably, the particle size of the granular oxygen absorption source 20 is in the range of 1 μm to 500 μm, and more preferably, the particle size of the granular oxygen absorption source 20 is in the range of 10 μm to 200 μm.

Claims

1. A vacuum heating device, comprising a sample chamber, a heating system and a vacuum pump for evacuating the sample chamber, It is characterized in that The sample chamber is provided with a placement for placing the sample, and a plurality of layers of oxygen absorption sources are arranged around the placement, and the plurality of layers of oxygen absorption sources are connected by a connecting piece, and the connecting piece is detachably connected to the sample chamber, and the heating system is used to heat the sample and the oxygen absorption source respectively; the connecting piece is a connecting plate with a groove or a plurality of connecting blocks with through holes; The oxygen absorption source comprises a substrate and an oxygen absorption layer coated on the substrate, wherein the oxygen absorption layer is made of an easily oxidizable metal material; The oxygen absorption layer is a composite coating with at least two layers, the outermost layer of the composite coating is a protective layer, and the protective layer is made of a metal that is easy to form a dense oxide film; The vacuum heating device also includes an atmosphere regulating device, which includes a gas source storing inert gas or reducing gas, a connecting pipeline connecting the gas source and the sample chamber, a gas flow meter, and a valve for controlling the gas source switch.

2. The vacuum heating device according to claim 1, It is characterized in that The oxygen absorption layer is coated by electroplating, chemical plating or vapor deposition.

3. The vacuum heating device according to claim 1, It is characterized in that The oxygen absorption source is in any one or more of the following forms: filamentous, flake-like, foamy, block-like, and granular.

4. The vacuum heating device according to claim 3, It is characterized in that The particle size range of the granular oxygen absorption source is 100nm-1mm.

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