CN114736029B - Ceramic welding device and method by microwave focusing method - Google Patents
Ceramic welding device and method by microwave focusing method Download PDFInfo
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- 238000005516 engineering process Methods 0.000 description 6
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- 229910000679 solder Inorganic materials 0.000 description 2
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Abstract
The invention discloses a device and a method for welding ceramics by a microwave focusing method, and relates to the technical field of microwave ceramic welding. The invention comprises a single-mode resonant cavity, a cover plate and an adjustable piston structure; a microwave power input port is arranged at one side of the single-mode resonant cavity, and the side surface opposite to the direction of the microwave power input port is a concave metal reflecting surface capable of focusing microwaves on one point after being reflected; the pressurizing mechanisms capable of pressurizing the ceramics to be subjected to microwave welding in the single-mode resonant cavity are symmetrically arranged at the other two opposite side parts of the single-mode resonant cavity, and the side parts of the single-mode resonant cavity are provided with vacuumizing ports. The invention has simple structure, easy control, uniform electric field and temperature distribution, stable operation, and can improve the problem of stress generated by nonuniform microwave field distribution, adopts the focusing reflection of the ellipsoidal curved surface to reflect and focus microwave beams, overcomes the defects of high requirement of the traditional non-focusing device on microwave source power, high manufacturing cost, and the like, improves the welding size of materials, and increases the variety of welding materials.
Description
Technical Field
The invention belongs to the technical field of microwave ceramic welding, and particularly relates to a microwave focusing method ceramic welding device and a microwave focusing method ceramic welding method.
Background
The use of microwaves to weld ceramics at high temperature is a new technology which has been rapidly developed in the recent years, and the welding technology has extremely high use value and wide development prospect; the ceramic material has good heat resistance and corrosion resistance, so that the ceramic material is used as a structural material to gradually replace a metal material in a high-temperature environment, the welding technology is widely applied to the industrial and scientific fields, such as aerospace, electronic information, chemical industry, ocean drilling and the like, and the microwave ceramic welding technology plays an increasingly important role in various fields due to the good characteristics.
The microwave welding utilizes the dielectric loss of microwave in the material to heat the ceramic, generate polarization and loss, and completes welding under certain pressure. As the temperature rising speed is high, the grains in the ceramic are not excessively enlarged, and the distribution of grain boundary phase elements is more uniform, the welding parts can be uniformly connected, thereby ensuring the excellent performance of the material.
The step of uniform heating in the ceramic welding process is taken as important and key, is an important premise for ensuring uniform sintering of large-size ceramic parts and ceramic parts with complex shapes, the good heating uniformity is the guarantee of welding strength, and the non-uniform heating phenomenon exists in the microwave heating sintering process, and when the non-uniform heating phenomenon is serious, extremely large residual stress can be generated, so that the ceramic parts are cracked. The main reasons can be divided into the following categories: (1) The microwave field is unevenly distributed, the approximate even area is extremely small, and a certain stress exists in the interior to influence the welding strength; (2) Heating phenomena specific to microwaves, such as hot spots, thermal runaway, selective heating; (3) Problems with the solder material itself, such as low thermal conductivity, oversized dimensions, large thermal expansion coefficient, complex structure, etc.; (4) The welding size of the welding material is problematic, and the uniform area of the microwave field of the microwave welding cavity is not large at present; the welding strength is required to be improved, and the selection of solder, the node loss and the matching performance with matrix materials are required to be improved; the welding size of the welding material is problematic, and the uniform area of the microwave field of the microwave welding cavity is not large at present; the welding strength needs to be improved, the selected area of the welding flux, the node loss and the matching property of matrix materials need to be improved, the types of welding materials need to be enriched, and the welding materials adopted at present are generally structural ceramics and have single application. Therefore, aiming at the problems, the device and the method for ceramic welding by the microwave focusing method have important significance.
Disclosure of Invention
The invention provides a device and a method for ceramic welding by a microwave focusing method, which solve the problems.
In order to solve the technical problems, the invention is realized by the following technical scheme:
the invention relates to a microwave focusing method ceramic welding device, which comprises a box-shaped single-mode resonant cavity with an open top and a cover plate which is movably arranged on the upper part of the single-mode resonant cavity and can realize airtight sealing;
one side of the single-mode resonant cavity is provided with a microwave power input port, and the opposite side is provided with an adjustable piston structure connected with a metal moving block in the single-mode resonant cavity; the metal moving block moves in the single-mode resonant cavity in a fine adjustment way through an adjustable piston structure, the side surface opposite to the direction of the microwave power input port is a concave metal reflecting surface capable of focusing microwaves on one point after being reflected, and an air-tight structure is arranged between the adjustable piston structure and the single-mode resonant cavity;
the pressurizing mechanism adopts a pressurizing rod to extend into the single-mode resonant cavity, and the end part of the pressurizing mechanism is provided with a contact capable of abutting and pressurizing the ceramic to be subjected to microwave welding, so that the position of the ceramic to be subjected to microwave welding after being clamped by the pressurizing is positioned in a range of a focusing point after microwave reflection, and an airtight structure is arranged between the pressurizing mechanism and the single-mode resonant cavity;
and a vacuumizing port is formed in the side part of the single-mode resonant cavity.
Further, a microwave focusing ceramic welding chamber is formed among the metal reflecting surface, the side wall of the single-mode resonant cavity opposite to the metal reflecting surface and the side walls of the two sides, and the pressurizing mechanism is symmetrically arranged on the two side walls of the microwave focusing ceramic welding chamber.
Further, wave-absorbing material layers are attached to two side walls of the microwave focusing ceramic welding chamber.
Further, the pressurizing mechanism comprises a second flange sleeve which is sleeved with a central hole of a first flange sleeve arranged on two side walls of the microwave focusing ceramic welding chamber and is in airtight fit with the central hole of the first flange sleeve, and a third flange sleeve which is connected with the second flange sleeve in a flange manner and is provided with a coaxial structure, and a pressurizing adjusting rod which is in airtight fit with central shaft holes of the second flange sleeve and the third flange sleeve is arranged at the rear end of the pressurizing rod.
The outer peripheral side of the third flange sleeve is provided with threads for rotation adjustment, and the threads are used for adjusting and controlling the air tightness of the center holes of the second flange sleeve and the first flange sleeve; the end part of the pressurizing adjusting rod is provided with a pressurizing device.
Further, the adjustable piston structure comprises a first mounting plate which corresponds to an opening hole formed in the side wall of the single-mode resonant cavity and is fixedly provided with an opening hole type, a sliding cavity which is arranged on the side part of the first mounting plate and is internally provided with a sliding hole, a piston rod which is arranged in the sliding cavity and is in airtight sliding fit with the sliding hole, and a screw cap which is arranged at the outer end part of the piston rod; the inner end of the piston rod is fixedly connected with the connecting blind hole at the rear part of the metal moving block.
Further, a vertical buckle is arranged on the cover plate, and a buckle seat which is matched with the vertical buckle to enable the cover plate and the single-mode resonant cavity to realize air sealing is arranged on the side part of the single-mode resonant cavity.
Further, the position of the microwave power input port is provided with an open hole type second mounting plate for airtight connection of the microwave input device.
A microwave focusing method ceramic welding method comprises the following steps:
s01, opening a cover plate of the single-mode resonant cavity, placing a ceramic material to be microwave welded in the microwave focusing ceramic welding cavity, adjusting the position of the ceramic material to be microwave welded, and then closing the cover plate to ensure the airtight seal of the interior of the single-mode resonant cavity;
s02, pressurizing the ceramic material to be microwave welded in the single-mode resonant cavity by a pressurizing mechanism, and vacuumizing to enable the ceramic material to be microwave welded to be closely attached together;
s03, using a microwave power supply as a microwave input device to introduce microwave energy into the single-mode resonant cavity, and adjusting the position of the metal reflecting surface through an adjustable piston structure to enable the microwave energy to be gathered on a welding block so as to start microwave welding;
s04, after welding is completed, opening the cover plate after natural cooling, taking out the microwave welding ceramic material, and completing welding.
Compared with the prior art, the invention has the following beneficial effects:
1. the ceramic welding device adopting the microwave focusing method has the advantages of simple structure, easy control, uniform electric field and temperature distribution, stable operation and capability of solving the problem of stress caused by uneven microwave field distribution;
2. according to the heating characteristic of the ceramic under the action of a microwave focusing mode, the input power is regulated through a power compensation system, and thermal runaway is restrained, so that the radial temperature gradient from the center to the surface of the material due to the size of the material is reduced;
3. during welding, the thickness of the middle layer and the grain size of the welding material are reduced, so that the joint strength can be improved;
4. in the welding process, the microwave focusing mode is utilized to improve the distribution of a microwave field and improve the thermal uniformity of a welding area, so that the welding size of materials is improved, the types of welding materials are increased, and the application of the microwave welding technology in the industrial field is wider;
5. the welding device adopts the focusing reflection of the ellipsoidal curved surface to reflect and focus the microwave beam, overcomes the defects of high requirement of the traditional non-focusing device on the microwave source power, high manufacturing cost, high cost and the like, and therefore, compared with the prior art, the invention has outstanding substantive characteristics and remarkable progress, the special focusing characteristic reduces the requirement of the device on the microwave source power, and realizes the welding strength of the ceramic welding device and the production yield of products.
Of course, it is not necessary for any one product to practice the invention to achieve all of the advantages set forth above at the same time.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed for the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a microwave focusing ceramic welding device according to the present invention;
FIG. 2 is a schematic view of the structure of the view angle A in FIG. 1;
FIG. 3 is an exploded view of a microwave focusing ceramic welding device according to the present invention;
FIG. 4 is a schematic view of the structure of the view B in FIG. 3;
FIG. 5 is a schematic view of the structure of the single-mode cavity of FIG. 1;
FIG. 6 is a top plan view of the structure of FIG. 5;
FIG. 7 is a cross-sectional view taken along line C-C of FIG. 6;
FIG. 8 is a cross-sectional view of the pressing mechanism of FIG. 3;
FIG. 9 is a cross-sectional view of the adjustable piston structure of FIG. 3;
in the drawings, the list of components represented by the various numbers is as follows:
the microwave oven comprises a 1-single-mode resonant cavity, a 101-vacuumizing port, a 102-clamping seat, a 103-wave absorbing material layer, a 104-first flange sleeve, a 1041-central hole, a 105-microwave power input port, a 1051-second fixing hole, a 1052-second mounting plate, a 106-opening hole, a 1061-first fixing hole, a 2-cover plate, a 3-metal moving block, a 301-metal reflecting surface, a 302-connecting blind hole, a 4-vertical clamping seat, a 5-adjustable piston structure, a 501-sliding cavity, a 502-piston rod, a 503-first mounting plate, a 504-nut, a 6-pressurizing mechanism, a 601-pressurizing adjusting rod, 602-contacts, 603-pressurizing rods, 604-second flange sleeve and 605-third flange sleeve.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In the description of the present invention, it should be understood that the terms "upper," "inner," "side," "socket," "center," and the like indicate an orientation or a positional relationship, and are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the components or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.
Referring to fig. 1-9, a ceramic welding device by a microwave focusing method according to the present invention; the single-mode resonant cavity 1 comprises a box-shaped single-mode resonant cavity 1 with an opening at the top and a cover plate 2 which is movably arranged at the upper part of the single-mode resonant cavity 1 and can realize air sealing, wherein the single-mode resonant cavity 1 is in a rectangular structure;
a microwave power input port 105 is arranged at one side of the single-mode resonant cavity 1, and an adjustable piston structure 5 connected with a metal moving block 3 inside the single-mode resonant cavity 1 is arranged at the other opposite side; the metal moving block 3 moves in the single-mode resonant cavity 1 in a fine adjustment way through the adjustable piston structure 5, the side surface opposite to the direction of the microwave power input port 105 is a concave metal reflecting surface 301 which can focus microwaves on one point after being reflected, and an airtight structure is arranged between the adjustable piston structure 5 and the single-mode resonant cavity 1;
the other two opposite side parts of the single-mode resonant cavity 1 are symmetrically provided with a pressurizing mechanism 6 which can pressurize the ceramic to be microwave welded in the single-mode resonant cavity 1, the pressurizing mechanism 6 adopts a pressurizing rod 603 to extend into the single-mode resonant cavity 1, the end part of the pressurizing mechanism is provided with a contact 602 which can be abutted against the ceramic to be microwave welded and pressurized, the position of the ceramic to be microwave welded after being pressurized and clamped is positioned in the range of focusing points after microwave reflection, and an airtight structure is arranged between the pressurizing mechanism 6 and the single-mode resonant cavity 1;
the side of the single-mode resonant cavity 1 is provided with a vacuum-pumping port 101.
The metal reflecting surface 301, the side wall of the single-mode resonant cavity 1 opposite to the metal reflecting surface 301 and the side walls on two sides form a microwave focusing ceramic welding chamber, and the pressurizing mechanism 6 is symmetrically arranged on the two side walls of the microwave focusing ceramic welding chamber; the microwave focusing ceramic welding chamber is a reflector region, and provides optical feedback capability to form continuous oscillation of stimulated radiation, so that the light beam is continuously enhanced, the direction and the frequency of the light beam are limited, and the output light beam has excellent directivity and monochromaticity.
Wherein, the two side walls of the microwave focusing ceramic welding chamber are adhered with wave absorbing material layers 103; the wave absorbing material layer 103 in this embodiment adopts PY-100 type darkroom wave absorbing material, specifically foamed plastic.
The pressurizing mechanism 6 comprises a second flange sleeve 604 which is in sleeve joint and airtight fit with a central hole 1041 of the first flange sleeve 104 arranged on two side walls of the microwave focusing ceramic welding chamber, a third flange sleeve 605 which is in flange connection with the second flange sleeve 604 and has a coaxial structure, and a pressurizing adjusting rod 601 which is in airtight fit with central shaft holes of the second flange sleeve 604 and the third flange sleeve 605.
Wherein, the outer circumference side of the third flange sleeve 605 is provided with a screw thread for rotation adjustment, which is used for adjusting and controlling the air tightness of the center holes of the second flange sleeve 604 and the first flange sleeve 104; the end of the pressure adjusting rod 601 is provided with a pressure device, and the pressure device adopts a hydraulic cylinder, a cylinder or an electric cylinder.
The adjustable piston structure 5 comprises a first mounting plate 503 with an opening hole corresponding to the opening hole 106 formed in the side wall of the single-mode resonant cavity 1 and fixedly mounted, a sliding cavity 501 mounted on the side part of the first mounting plate 503 and internally provided with a sliding hole, a piston rod 502 mounted in the sliding cavity 501 and hermetically matched with the sliding hole, and a nut 504 mounted at the outer end part of the piston rod 502; the inner end of the piston rod 502 is fixedly connected with the connecting blind hole 302 at the rear part of the metal moving block 3; a first fixing hole 1061 corresponding to the positioning hole of the opening hole 106 on the side part of the single-mode resonant cavity 1 is formed on the surface of the first mounting plate 503, and is fixedly connected with the first mounting plate through a screw in a gas-tight manner; the adjustable piston structure 5 changes the focusing of the metal reflecting surface 301 by reciprocating motion, and controls the microwave at one point in a centralized way, thereby increasing the welding strength and accuracy.
The cover plate 2 is provided with a vertical buckle 4, and the side part of the single-mode resonant cavity 1 is provided with a buckle seat 102 which is matched with the vertical buckle 4 to enable the cover plate 2 and the single-mode resonant cavity 1 to realize airtight seal; the cavity is used for fixing the single-mode resonant cavity 1, so that the cavity is kept sealed.
Wherein, the position of the microwave power input port 105 is provided with an open hole type second mounting plate 1052 for airtight connection of the microwave input device; the surface of the second mounting plate 1052 is provided with a second fixing hole 1051 corresponding to the position of the microwave power input port 105 on the side part of the single-mode resonant cavity 1, and the second fixing hole 1051 is fixedly connected with the microwave power input port by a screw in a sealing way; the second mounting plate 1052 is fixedly connected with the microwave input device port; the microwave power input 105 is used for providing microwave power required for welding, in particular a microwave power supply, to the microwave input device.
A microwave focusing method ceramic welding method comprises the following steps:
s01, opening a cover plate 2 of the single-mode resonant cavity 1, placing a ceramic material to be microwave welded in the microwave focusing ceramic welding cavity, adjusting the position of the ceramic material to be microwave welded, and then closing the cover plate 2 to ensure the airtight seal of the interior of the single-mode resonant cavity 1;
s02, pressurizing ceramic materials to be microwave welded in the single-mode resonant cavity 1 through a pressurizing mechanism 6, and vacuumizing to enable the ceramic materials to be microwave welded to be closely attached together;
s03, a microwave power supply is adopted as a microwave input device for introducing microwave energy into the single-mode resonant cavity 1, the position of the metal reflecting surface 301 is adjusted through the adjustable piston structure 5, so that the microwave energy is gathered on a welding block, and microwave welding is started;
s04, after welding is completed, opening the cover plate 2 after natural cooling, taking out the microwave welding ceramic material, and completing welding.
The microwave welding utilizes the dielectric loss of the material to generate heat, and the whole device of the technical scheme has the advantages that only a welding area is at high temperature, and the rest part is still at a normal temperature cold state, so the whole device has simple and compact structure and low use cost. The whole inside heats simultaneously during welding, the internal stress is low, the fracture is not easy to generate, the ceramic can be uniformly and firmly combined together, the appearance of the ceramic is not changed, and meanwhile, the preheating and the post-treatment are not needed. The microwave welding is not easy to generate air bubbles or grow grains at the welding part because the microwave welding can be heated rapidly and the temperature can be controlled accurately, and meanwhile, the grain boundary element distribution is more uniform.
The device is realized by the technical measures: a microwave focusing welding device under a vacuum environment is characterized in that a focusing reflecting surface is arranged at one end in a vacuum cavity, a microwave receiving end is arranged at the other end of the focusing reflecting surface, and the focusing reflecting surface is an ellipsoidal concave surface. The microwave signal generated by the microwave source is transmitted to the focusing reflecting surface after passing through the receiving port, the focusing reflecting surface focuses the microwave signal, a local strong electromagnetic field is formed in a vacuum environment, microwaves which are not focused in vacuum and scattered can be absorbed by the wave absorbing material attached to the inner wall of the vacuum cavity, and the metal reflecting surface is selected as the focusing reflecting surface. The position of the metal reflecting surface is changed by moving, the reflecting surface is controlled to reciprocate, a proper position is found to be static, and under the condition that the welding size of microwaves is unchanged, the standing wave position of the microwaves and the thermal uniformity of the microwave welding are ensured.
The microwave welding is to heat ceramics by utilizing dielectric loss of microwaves in materials to generate polarization and loss, finish welding under certain pressure, and divide the microwave welding into two types according to whether an intermediate medium needs to be added between the materials or not: direct welding and indirect welding.
The main body of the high-temperature welding ceramic adopts a rectangular resonant cavity, the working frequency of a microwave source is 2.45GHz, the power is continuously adjustable from 0W to 3000W, the surface temperature of the material is measured by an optical fiber infrared radiation thermometer, the welding temperature is represented by adjusting the power of the microwave source, and the pressure required by welding is applied by a pressurizing device. Dielectric properties epsilonr and tg delta of the ceramic during the ceramic welding process may change drastically with increasing temperature to cause a drift in the resonant frequency and coupling degree of the cavity. Accordingly, the position of the shorting piston and the size of the coupling hole need to be adjusted accordingly to compensate for this drift to maintain the critical coupling state and the continuity of resonance to achieve the desired welding temperature. According to perturbation theory, the distance L of the short-circuit piston movement and the relation between the size of the coupling hole and the frequency drift and the material performance are expressed by the following formulas:
l= { V- [ f 0/(f 0-f 1) ] a (εr-f) V0} and
W＝(2a/π)arctg{[fI/(afu)][(6πα∈rtgδ)/V]1/8}3/8；
wherein a is the width dimension of the cavity, alpha is a constant, fI and fu are respectively the resonant frequencies before and after frequency drift, V0 is the volume of the material, V is the volume of the cavity, epsilon r and tg delta are respectively the relative dielectric constant and loss tangent of the material, and the design of a shorting piston and coupling tuning is the key for obtaining the cavity with excellent welding performance.
Impedance matching of the resonant cavity and an external circuit is achieved through a coupling hole, and for materials with dielectric loss changing sharply with temperature, drift of coupling degree often plays a decisive role on absorption efficiency, so that a fixed aperture diaphragm is adopted. The choke structure is adopted, so that the impedance of the high current position of the coupling window is reduced as much as possible, the heating phenomenon in the coupling window is effectively restrained during welding, and the Q value of the cavity is improved in a multiplied mode.
The nature of microwave heating is that the extent of electromagnetic interaction of a material and the ability of the material to absorb microwaves can be described by the complex dielectric constant epsilon: ε, =ε, -j ε;
wherein: ε, dielectric constant, ε, -dielectric loss tangent, ε o, dielectric constant in vacuum, εr, relative dielectric constant, tg delta, dielectric loss tangent;
upon microwave heating, the microwave energy Ps absorbed per unit volume of material can be expressed as:
Ps＝2πfεoεrtgδ·E2；
wherein: f-microwave frequency; e-electric field strength inside the material;
when the microwave propagates in the material, the microwave energy is attenuated, and the power penetration depth D1/D2 of the microwave is defined as the microwave power, the distance from the surface of the material to the surface value 1/2, can be calculated by the following formula:
D1/2＝(3λ_0)/〖8.686πtgδ(ε_r/ε_0)〗^(1/2)；
wherein: λ0—the wavelength of the microwaves in free space; after the material absorbs microwave energy, its rate of temperature rise may be determined by:
ΔT/Δt＝ε_(rtgδ·f·E^2)/(ρ·C_p)
wherein: delta t—temperature increment; c_p-specific heat of material; ρ—material density;
the dielectric loss factor epsilon_rtgdelta of the ceramic material at room temperature is extremely small, but increases rapidly with the increase of temperature, namely the temperature rise phenomenon, and the value epsilon_rtgdelta of the ceramic material at room temperature is extremely small, but the value of the ceramic material is rapidly increased due to the rise phenomenon, generally the ceramic material has smaller thermal conductivity than metal, the fact that the temperature rise phenomenon and the thermal conductivity coefficient are low is utilized to ensure that the temperature of a ceramic welding part is the highest, and the ceramic material is rapidly cooled from the welding part to a non-connecting end, and the ceramics can be effectively and firmly connected together through the temperature distribution.
The beneficial effects are that:
1. the ceramic welding device adopting the microwave focusing method has the advantages of simple structure, easy control, uniform electric field and temperature distribution, stable operation and capability of solving the problem of stress caused by uneven microwave field distribution;
2. according to the heating characteristic of the ceramic under the action of a microwave focusing mode, the input power is regulated through a power compensation system, and thermal runaway is restrained, so that the radial temperature gradient from the center to the surface of the material due to the size of the material is reduced;
3. during welding, the thickness of the middle layer and the grain size of the welding material are reduced, so that the joint strength can be improved;
4. in the welding process, the microwave focusing mode is utilized to improve the distribution of a microwave field and improve the thermal uniformity of a welding area, so that the welding size of materials is improved, the types of welding materials are increased, and the application of the microwave welding technology in the industrial field is wider;
5. the welding device adopts the focusing reflection of the ellipsoidal curved surface to reflect and focus the microwave beam, overcomes the defects of high requirement of the traditional non-focusing device on the microwave source power, high manufacturing cost, high cost and the like, and therefore, compared with the prior art, the invention has outstanding substantive characteristics and remarkable progress, the special focusing characteristic reduces the requirement of the device on the microwave source power, and realizes the welding strength of the ceramic welding device and the production yield of products.
The preferred embodiments of the invention disclosed above are intended only to assist in the explanation of the invention. The preferred embodiments are not exhaustive or to limit the invention to the precise form disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best understand and utilize the invention. The invention is limited only by the claims and the full scope and equivalents thereof.
Claims (4)
1. A ceramic welding device by a microwave focusing method is characterized in that:
the device comprises a box-shaped single-mode resonant cavity (1) with an open top and a cover plate (2) which is movably arranged at the upper part of the single-mode resonant cavity (1) and can realize air sealing;
a microwave power input port (105) is arranged at one side of the single-mode resonant cavity (1), and an adjustable piston structure (5) connected with a metal moving block (3) in the single-mode resonant cavity (1) is arranged at the other opposite side of the single-mode resonant cavity; the metal moving block (3) moves in the single-mode resonant cavity (1) in a fine adjustment way through the adjustable piston structure (5), the side surface opposite to the direction of the microwave power input port (105) is a concave metal reflecting surface (301) capable of focusing microwaves on one point after being reflected, and an airtight structure is arranged between the adjustable piston structure (5) and the single-mode resonant cavity (1);
the pressurizing mechanism (6) capable of pressurizing the ceramic to be microwave welded in the single-mode resonant cavity (1) is symmetrically arranged at the other two opposite side parts of the single-mode resonant cavity (1), the pressurizing mechanism (6) stretches into the single-mode resonant cavity (1) by adopting a pressurizing rod (603), and the end part of the pressurizing mechanism is provided with a contact (602) capable of abutting the ceramic to be microwave welded and pressurizing, so that the position of the ceramic to be microwave welded after being pressurized and clamped is located in a focusing point range after microwave reflection, and an airtight structure is arranged between the pressurizing mechanism (6) and the single-mode resonant cavity (1);
a vacuumizing port (101) is formed in the side part of the single-mode resonant cavity (1);
the microwave focusing ceramic welding cavity is formed among the metal reflecting surface (301), the side wall of the single-mode resonant cavity (1) opposite to the metal reflecting surface (301) and the side walls at two sides, and the pressurizing mechanism (6) is symmetrically arranged on the two side walls of the microwave focusing ceramic welding cavity;
the pressurizing mechanism (6) comprises a second flange sleeve (604) which is sleeved with a central hole (1041) of a first flange sleeve (104) arranged on two side walls of the microwave focusing ceramic welding chamber and is in airtight fit, a third flange sleeve (605) which is in flange connection with the second flange sleeve (604) and has a coaxial structure, and a pressurizing adjusting rod (601) which is in airtight fit with the central shaft holes of the second flange sleeve (604) and the third flange sleeve (605) is arranged at the rear end of the pressurizing rod (603);
the outer periphery of the third flange sleeve (605) is provided with threads for rotation adjustment, and the threads are used for adjusting and controlling the air tightness of the center holes of the second flange sleeve (604) and the first flange sleeve (104); the end part of the pressurizing adjusting rod (601) is provided with a pressurizing device;
the adjustable piston structure (5) comprises a first mounting plate (503) which corresponds to an opening hole (106) formed in the side wall of the single-mode resonant cavity (1) and is fixedly provided with an opening hole type, a sliding cavity (501) which is arranged on the side part of the first mounting plate (503) and is internally provided with a sliding hole, a piston rod (502) which is arranged in the sliding cavity (501) and is in airtight sliding fit with the sliding hole, and a screw cap (504) which is arranged at the outer end part of the piston rod (502); the inner end part of the piston rod (502) is fixedly connected with a connecting blind hole (302) at the rear part of the metal moving block (3);
the cover plate (2) is provided with a vertical buckle (4), and the side part of the single-mode resonant cavity (1) is provided with a buckle seat (102) which is matched with the vertical buckle (4) to enable the cover plate (2) and the single-mode resonant cavity (1) to realize airtight sealing.
2. The microwave-focused ceramic welding device according to claim 1, wherein a wave-absorbing material layer (103) is attached to both side walls of the microwave-focused ceramic welding chamber.
3. A microwave-focused ceramic welding apparatus as claimed in claim 1, characterized in that the microwave power input port (105) is provided with an open-cell second mounting plate (1052) for the airtight connection of the microwave input device.
4. A method for welding ceramics by a microwave focusing method, which is characterized in that a device for welding ceramics by a microwave focusing method according to any one of claims 1 to 3 is adopted, comprising the following steps:
s01, opening a cover plate (2) of the single-mode resonant cavity (1), placing ceramic materials to be microwave welded in the microwave focusing ceramic welding cavity, adjusting the positions of the ceramic materials to be microwave welded, and then closing the cover plate (2) to ensure airtight sealing in the single-mode resonant cavity (1);
s02, pressurizing ceramic materials to be subjected to microwave welding in the single-mode resonant cavity (1) through a pressurizing mechanism (6), and vacuumizing to enable the ceramic materials to be subjected to microwave welding to be closely attached together;
s03, a microwave power supply is adopted as a microwave input device to guide microwave energy into the single-mode resonant cavity (1), the position of the metal reflecting surface (301) is adjusted through the adjustable piston structure (5), so that the microwave energy is gathered on a welding block, and microwave welding is started;
s04, after welding is completed, opening the cover plate (2) after natural cooling, taking out the microwave welding ceramic material, and completing welding.
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| CN110006077A (en) * | 2019-05-05 | 2019-07-12 | 上海海洋大学 | A method of improving the heating uniformity of microwave oven by continuously adjusting the position of reflecting surface |
| CN217265477U (en) * | 2022-04-09 | 2022-08-23 | 上海财盈半导体股份有限公司 | Microwave focusing method ceramic welding device |
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| US9504098B2 (en) * | 2012-10-11 | 2016-11-22 | Btu International, Inc. | Furnace system having hybrid microwave and radiant heating |
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|---|---|---|---|---|
| JPH08217558A (en) * | 1995-02-15 | 1996-08-27 | Mitsubishi Heavy Ind Ltd | Ceramic bonding device |
| CN102869182A (en) * | 2012-09-12 | 2013-01-09 | 清华大学 | Large-volume microwave plasma generating device based on coupling window radiation |
| CN104345236A (en) * | 2014-10-29 | 2015-02-11 | 中国工程物理研究院应用电子学研究所 | Device for simulating focusing of microwaves in vacuum environment |
| CN105170981A (en) * | 2015-10-12 | 2015-12-23 | 福州大学 | Microwave hot-pressing sintering and brazing device and using method thereof |
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