KR102287257B1 - Device for Brazing using Electron Beam and Induction coil and Method for Controlling the Same - Google Patents

Abstract

The present invention relates to a dissimilar material brazing device using an induction coil and an electron beam, capable of maximizing the yield and shortening process time to prevent material properties from being altered during a process. In accordance with one aspect of the present invention, provided is the dissimilar material brazing device comprising: an electron beam emitting device comprising a cathode and an anode; a chamber irradiated with an electron beam emitted from the electron beam emitting device and placing a bonding object comprising a first base material of an electrically conductive material and a second base material of a nonconductive material to be mutually bonded; an induction coil positioned on the surface of the bonding object and heating the first base material of the bonding object by induction heating by an applied current; and a control unit for controlling the electron beam emitted from the electron beam emitting device to heat the second base material of the bonding object and the induction coil to heat the first base material of the bonding object.

Description

Device for Brazing using Electron Beam and Induction coil and Method for Controlling the Same

The present invention relates to a brazing apparatus of dissimilar materials using an induction coil and an electron beam, and more particularly, an induction coil capable of maximizing the yield and shortening the process time, thereby preventing the properties of the material from being denatured during the process; It relates to a brazing apparatus of different materials using an electron beam.

In general, brazing is a method in which a filler (filler) is placed between both base materials to be joined and then heated to melt the filler to join both base materials. It refers to the method of joining.

Such bonding using brazing is often used when bonding both base materials of different materials for electrical insulation of electrical components that use high voltage, such as capacitors, or when sealing parts that form a vacuum among cooler components. It is also used in the case of the same type of material, but it is mainly used when the sheep base material is a different material. For example, it is mainly used when joining ceramics and ceramics, which is impossible by melting the existing base material, or when joining different materials such as ceramics and metals.

On the other hand, cutting tools such as insert tips, drill tools, milling tools, etc. are widely used in industrial fields, and are a basic technological element that has a lot of demand and influences on major industrial fields such as automobiles, molds, aviation, electricity, and semiconductors.

For example, a cutting tool such as an insert tip is mainly used for lathe processing, etc., as shown in FIG. 1 , a shank layer 12 generally having a rhombus shape such as diamond, and a corner of the shank layer 12 . A cutting layer 14 made of a material such as ceramic that is resistant to wear is provided.

In general, the shank layer 12 is made of a metal material that is resistant to breakage, has high thermal conductivity, and is electrically conductive, and the cutting layer is resistant to wear and is made of a material such as non-conductive ceramic, and is made of different materials.

Such an insert tip may be manufactured in various ways, but among them, a method of bonding the cutting layer 14 to the shank layer 12 by a brazing method is used.

That is, after placing a filler 16 such as silver or nickel alloy between the shank layer 12 and the cutting layer 14 , as shown in FIG. 2 , it is placed in the brazing furnace 20 and then heated. to braze

When brazing the shank layer 12 and the cutting layer 14, the filler 16 is heated slowly so as not to be twisted or broken due to the difference in thermal deformation, and heated above the melting temperature of the metal constituting the filler 16. Brazing can be completed as the molten filler 16 is solidified by melting it and then cooling it slowly.

The cutting tool 10 is not only an insert tip used for a lathe, but also a tool used for drilling a hole or a general-purpose cutting tool, such as milling, by separately forming a cutting layer forming a part to be actually cut, welding, brazing, etc. It is manufactured by joining.

However, this conventional brazing method has the following problems.

First, since the heating furnace 20 is used, the operation is made in units of the heating furnace 20, which is advantageous for small-scale mass production, but has a disadvantageous problem for multi-type small-scale production.

Second, since the method using the heating furnace 20 heats/cools very slowly to prevent crack generation during thermal expansion and thermal contraction of the bonding object 10, it takes several days for the brazing operation, resulting in low productivity.

Third, since the heating furnace 20 is used to inject and heat the same amount of heat (energy) into both the base material and the filler, when dissimilar materials with different coefficients of thermal expansion of both base materials are used, the amount of thermal expansion of both base materials is different and cracks There is a problem that productivity is low because the probability of occurrence of defects such as occurrence is very high.

Fourth, the conventional brazing method took a long time to reduce productivity, and there was a problem in that the yield varies depending on the skill level of the operator handling the brazing furnace. In addition, if the brazing is heated at a high temperature for a long time during heating, a grain-growth phenomenon occurs in which the crystals of the shank layer and the cutting layer grow, and the ceramic of the cutting layer has reduced wear resistance or reduced mechanical strength ( tungsten kaide, etc.), and sometimes problems such as material deformation and damage (PCD, etc.) occur due to high temperature.

Fifth, in the selection of the material of the bonding layer to prevent grain growth, the melting point is generally high, the hardness (approximately 638 MPa, Hv) is strong, the toughness is good, the damping performance (maximum z = 0.035) is excellent, and the shock absorption is good Materials such as nickel cannot be used, and materials such as silver with a low melting temperature are used, but the hardness (250 MPa, Hv) is low, so the shock absorption is not good due to the limitation of rigidity. It has limitations.

Sixth, since the shank layer and the cutting layer are supplied with the same amount of heat during the brazing process of FIG. 2, when the coefficient of thermal expansion of the material constituting the shank layer and the cutting layer is greatly different, the amount of thermal expansion is greatly different and cracking or warping This may occur, and the material of the shank layer and the cutting layer must be selected only with a material that does not have a large coefficient of thermal expansion, so there is a limited problem in the selection of the material.

Seventh, in general, for the cutting layer actually cut by a cutting tool, a ceramic-based material such as WC (tungsten carbide) with excellent wear resistance is widely used, but the ceramic material is a non-conductive material and it is impossible to process it with an electron beam.

The present invention is to solve the above problems, and the present invention is an induction coil with improved productivity, no crystal grain denaturation, improved yield, and free choice of material because brazing of non-conductive materials is possible. It is a task to provide a brazing apparatus of dissimilar materials using an electron beam and an electron beam.

The problems of the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

In order to solve the above problems, according to one aspect of the present invention, an electron beam emitting device including a cathode and an anode, an electron beam emitted from the electron beam emitting device is irradiated, and an electrically conductive material that is bonded to each other is not A chamber in which a bonding object including a second base material of an electrically conductive material is located, an induction coil positioned on the surface of the bonding object and heating the first base material of the bonding object by induction heating by an applied current, the electron beam emission There is provided a dissimilar material brazing apparatus including a control unit for controlling the electron beam irradiated from the device to heat the second base material of the bonding object, and control the induction coil to heat the first base material of the bonding object.

The controller may control the amount of thermal expansion per unit time of the first base material and the second base material to be the same.

The control unit may control the amount of heat shrinkage per unit time of the first base material and the second base material to be the same.

The induction coil may be positioned on the surface of the second base material of the bonding object.

The induction coil may be positioned on the surface of the first base material of the bonding object.

The induction coil may be formed to have a hollow cross-section so that coolant flows therein.

It may include a conductive layer provided to cover the second base material by being connected to the surface to which the electron beam of the second base material of the bonding object is irradiated, and a ground wire for grounding the conductive layer.

Meanwhile, according to another aspect of the present invention, a filler is placed between the first base material of an electrically conductive material and the second base material of a non-conductive material, and the filler is melted by heating it to bond the first base material and the second base material In the control method of a dissimilar material brazing apparatus, the method of controlling a dissimilar material brazing apparatus comprising an induction current heating step of heating a first base material by operating an induction coil, and an electron beam irradiation step of heating a second base material as an electron beam is provided do.

The induced current heating step and the electron beam irradiation step may be heated so that the amount of thermal expansion per time of the first base material and the second base material is the same.

After the bonding of the first base material and the second base material is completed, the method may further include a cooling step of cooling the first base material and the second base material.

In the cooling step, the induction coil and the electron beam may be controlled so that the heat shrinkage rate per time of the first base material and the second base material are the same.

According to the brazing apparatus of different materials using the induction coil and the electron beam of the present invention, there are the following effects.

First, since the first base material of the electrically conductive material is heated using an induction coil, and the second base material of the non-conductive material is heated separately using an electron beam, the first base material and the second base material can be heated independently. Control of heating may be easier.

Second, by brazing using an induction coil and an electron beam, the first base material and the second base material can be heated so that the amount of thermal expansion is the same. Even if it is large, it is possible to prevent the occurrence of a phenomenon in which the second base material is broken or twisted during the brazing process.

Third, by heating the non-conductive second base material using electron beam brazing, the heating time is greatly shortened, and heating can be terminated before the second base material and the grain growth phenomenon inside the first base material occur, so that the first The grain growth phenomenon (carbide size in the case of steel, etc.) of the base material and the second base material can be prevented. Therefore, it is possible to secure the process reproducibility and stability for securing the abrasion resistance and rigidity of the first base material and the second base material.

Fourth, as a material of the bonding interface layer, a nickel-based alloy having a high melting point but excellent bonding strength and heat resistance temperature and excellent internal damping characteristics can be used.

Fifth, in the prior art, the material selection was not free because the first base material and the second base material had to be selected as materials having the same coefficient of thermal expansion as possible. Therefore, it is possible to apply the difference in the coefficient of thermal expansion of the first base material and the second base material, so the material selection is free.

Sixth, conventionally, it was difficult to process a non-conductive material such as ceramics using an electron beam, but according to the present invention, a grounded conductive layer is formed on the surface of the non-conductive material layer, so that electron beam irradiation is possible, so the choice of material is free.

Effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

The summary set forth above as well as the detailed description of the preferred embodiments of the present application set forth below may be better understood when read in conjunction with the accompanying drawings. For the purpose of illustrating the invention, there are shown in the drawings preferred embodiments. It should be understood, however, that the present application is not limited to the precise arrangements and instrumentalities shown.
1 is a perspective view showing a conventional general insert tip cutting tool;
Figure 2 is a view showing a state of brazing the insert tip cutting tool of Figure 1 in a general brazing furnace;
3 is a view showing an embodiment of a brazing apparatus of different materials using an induction coil and an electron beam according to an embodiment of the present invention;
Figure 4 is a view showing a state in which the induction coil of Figure 3 is disposed on the insert tip cutting tool;
5 is a cross-sectional view showing a state in which the first base material and the second base material are heated by the induced current and electron beam irradiation generated by the induction coil;
6 is a view showing a cross-section of the induction coil of FIG. 3;
7 is a cross-sectional view showing a state in which the induction coil is disposed so as to be in contact with the first base material, and a conductive layer and a ground wire are provided on the surface of the second base material;
8 is a view illustrating a state in which a conductive layer is formed on the surface of an insert tip cutting tool using a carbon nanotube solution;
9 is a flowchart showing a control method of a dissimilar material brazing apparatus according to another aspect of the present invention;
10 is a graph showing the difference in the temperature rise of the first base material and the second base material according to the difference in the initial preheating temperature;
11 is a graph showing a state in which the first base material and the second base material are heated so that the amount of thermal expansion is the same;
12 is a graph showing the difference in heat shrinkage when the first base material and the second base material are naturally cooled;
13 is a graph when the first base material and the second base material are cooled so that the amount of heat shrinkage is the same in the cooling step; And,
14 is a graph when cooling while heating the first base material intermittently so that the heat shrinkage of the first base material and the second base material are similar in the cooling step.

Hereinafter, preferred embodiments of the present invention in which the object of the present invention can be specifically realized will be described with reference to the accompanying drawings. In describing the present embodiment, the same names and the same reference numerals are used for the same components, and an additional description thereof will be omitted.

Hereinafter, an embodiment of a brazing apparatus of a dissimilar material using an induction coil and an electron beam of the present invention (hereinafter, referred to as a 'dissimilar material brazing apparatus for convenience of description) will be described.

As shown in FIG. 3, the dissimilar material brazing apparatus according to this embodiment is an electron beam emitting apparatus 100, a chamber 210, a stage 220, an induction coil 230, a cooling unit 240, and a control unit 280. may include.

The electron beam emitting device 100 includes a cathode 120 and an anode 130 to emit an electron beam.

In this embodiment, the electron beam emitting device 100 will be described by taking as an example that a plasma type electron beam emitting device is provided. The electron beam emitting device 100 will be described as an example of applying a cold type plasma electron beam emitting device including a housing 150 , a cathode 120 , an anode 130 and an insulating holder 140 . .

The housing 150 is a component that forms a space in which a cathode 120 and an anode 130, which will be described later, are located, in which an electron beam is accelerated, and an emission port 156 through which the accelerated electron beam is emitted is formed on the other side. In addition, the inside of the housing 150 may form a vacuum atmosphere. At this time, the degree of vacuum formed inside the housing 150 may be about 10^-3 Torr.

In addition, a cathode 120 is provided on one side of the housing 150 . The cathode 120 is a component that receives electric energy and emits electrons, and in this embodiment, it will be described by taking as an example that it is made of a metal material and has the overall shape of a disk having a predetermined thickness.

The anode 130 may be positioned to be spaced apart from the cathode 120 to the other side within the housing 150 . The anode 130 is a component that accelerates electrons emitted from the cathode 120 by receiving electrical energy, and an opening 132 through which the accelerated electrons pass may be formed.

Meanwhile, the insulating holder 140 insulates between the cathode 120 and the housing 150 , and is a component for fixing the cathode 120 to the housing 150 .

In addition, a driving unit 160 for supplying electric energy to the cathode 120 or the anode 130 and a cooling unit (not shown) for cooling the cathode 120 may be provided on one side of the insulating holder 140 .

And, although not shown in the drawing, the other side of the anode 130 is provided with a focusing part (not shown) and a deflector 170 for focusing or deflecting the electron beam that has passed through the opening 132 of the anode 130 . can

Therefore, when electric energy is applied to the cathode 120 and the anode 130 , electrons are emitted from the cathode 120 and accelerated toward the anode 130 , and then emitted through the outlet 156 of the housing 150 . can be

On the other hand, the cathode 120 may be formed so that the surface facing the anode 130 is concave to form a gradient.

And, the edge 122 of the surface on which the gradient is formed of the cathode 120 may be formed to be round.

Therefore, since a sharp tip is not formed on the edge of the cathode 120 , arc generation is prevented and more stable operation is possible.

In addition, the insulating holder 140 is formed to surround the rear surface of the surface on which the gradient of the cathode 120 is formed and the side surface of the cathode 120 , the insulating holder 140 is the side surface of the cathode 120 . The enclosing portion may be formed to extend to the rounded portion 122 of the rim of the cathode.

In addition, since the insulating holder 140 extends to the side of the cathode 120 , it is possible to prevent arcing between the housing 150 and the cathode 120 .

In this case, the insulating holder 140 may be formed to extend to surround a portion of the rounded portion of the cathode edge 122 .

That is, the cathode 120 may be located closer to the anode 130 than the insulating holder 140 .

As described above, since the rim of the cathode 120 is formed to be rounded, a space may be formed between the insulating holder 140 and the cathode 120, and in this case, the space is This may cause arcing during operation of the electron beam emitting device.

Accordingly, since the cathode 120 is positioned closer to the anode 130 than the insulating holder 140 , the gap between the cathode 120 and the insulating holder 140 is reduced, so that a space in which electric charges are stored can be reduced.

Accordingly, since the capacitance between the cathode 120 and the insulating holder 140 is reduced and arc generation is suppressed, it is possible to operate more stably and to increase the limit output more.

Meanwhile, the housing 150 may include a tube 152 forming a periphery of the side thereof.

In this case, the tube 152 may be formed of a metal material, and may be insulated from the cathode 120 and the anode 130 . To this end, an insulator 154 may be provided between the tube 152 and the cathode 120 .

In addition, a ground 158 may be formed.

When metal is processed by the electron beam emitting device, metal vapor is generated from the molten metal, and the generated metal vapor may be deposited on the inner surface of the tube 152 .

At this time, since the tube 152 is grounded 158, electrons around the metal vapor attached to the inner surface of the tube 152 flow to the ground 158 to prevent arcing. Stable operation is possible, and the limit output can be raised at the same time.

In addition, due to the characteristics of the metal material, it is strong against external impact and repeated thermal shock, and it can be operated without removing the attached metal vapor, so that it can be used semi-permanently.

In addition, a reflective electron blocking structure 160 may be provided.

A portion of the outer portion of the electron beam e emitted from the cathode 120 may not be directed toward the anode 130 , but may form backscattered electrons (BSE) that move in a different direction.

In addition, secondary electrons generated by collision of elements such as nitrogen remaining in the tube 152 with accelerated electrons may be generated.

In the following description, the backscattered electrons and the secondary electrons will be collectively referred to as reflection electrons.

These reflected electrons may not be focused as compared to the electron beam e passing through the anode 130 , and thus may have no directionality or may be scattered.

These reflected electrons may be reflected within the housing 150 to heat the tube 152 or generate an arc. The tube 152 of the electron beam emitting device 100 of this embodiment is formed of a metal material such as stainless Therefore, when the tube 152 is heated and thermally expanded, the geometrical condition is changed, so that the precision of the electron beam emitting device 100 may be deteriorated.

Accordingly, the reflective electron blocking structure 160 is a component that blocks these reflective electrons from being directed to the inside of the tube 150 .

The reflective electron blocking structure 200 may be formed to extend toward the anode 130 from around the emission hole 156 of the surface where the emission hole 156 of the housing 150 is formed.

Accordingly, the reflective electron blocking structure 160 is disposed between the anode 130 and the surface on which the emission hole 156 is formed, and extends from the surface on which the emission hole 156 is formed toward the anode 130 . may be in the form of

At this time, the reflective electron blocking structure 160 has an opening on the side facing the anode 130 and the side facing the discharge port 156, and the hollow can communicate with the anode 130 and the emission port 156. there is.

Accordingly, the hollow of the reflective electron blocking structure 160 may serve as a passage through which electrons accelerated through the opening 132 of the anode 130 are emitted to the emission port 156 .

At this time, on the other hand, the hollow may be formed to have a larger diameter than the discharge port 156 on the same axis as the discharge port 156, smaller than or equal to the diameter of the opening 132 of the anode 130. can be formed.

In addition, the discharge port 156 may be formed to have a smaller diameter than the opening 132 of the anode 130 .

In addition, a flange portion 162 extending inwardly from the inner circumferential surface of the reflective electron blocking structure 160 may be formed. The flange portion 210 may be formed on an upper side of the reflective electron blocking structure 160, The length at which the flange portion 210 protrudes may be such that accelerated electrons passing through the opening 132 of the anode 130 do not interfere with passing through the reflective electron blocking structure 160 .

In addition, when processing metal as the electron beam emitting device, metal vapor may be generated from the molten metal. These metal vapors are introduced into the housing 150 through the discharge port 156 and deposited on the tube 152 or Alternatively, an arc may be generated when deposited on the insulating holder 140 . However, when the metal vapors are deposited on the surface forming a concave gradient of the cathode 120 , the metal vapors may not be deposited but may be evaporated due to the high energy of the electron beam.

Therefore, the diameter of the flange portion 162 is formed to a diameter that can guide the metal vapor flowing in through the discharge port 156 toward the surface forming the concave gradient of the cathode 120 without spreading in the housing. can be

The accelerated electrons passing through the opening 132 of the anode 130 may be emitted to the emission port 156 of the housing 150 through the hollow of the reflective electron blocking structure 160 .

On the other hand, the reflective electrons may not pass through the emission hole 156 of the housing 150 and may be reflected on the surface on which the emission hole 156 of the housing 150 is formed.

At this time, the reflected electrons are reflected within the inner circumferential surface of the reflective electron blocking structure 160 and re-reflection toward the tube 152 may be blocked.

Since the flange portion 162 extends inside the inner circumferential surface, electrons reflected in the hollow of the reflective electron blocking structure 160 are prevented from escaping to the outside of the reflective electron blocking structure 160 and at the same time, the emission port 156 ), the metal vapor introduced through the housing does not spread in the housing, but is guided toward the surface forming the concave gradient of the cathode 120 to prevent the metal vapor from being deposited on the tube 152 or the insulating holder 140. there is.

In addition, a plurality of absorbing grooves 164 are provided on the inner peripheral surface of the reflective electron blocking structure 160 to increase the probability of collision between the reflective electrons and the plurality of grooves 164 , and electrons reflected from the hollow inner peripheral surface of the reflective electron blocking structure 160 . can absorb them.

On the other hand, the reflective electron blocking structure 160 may be heated by reflective electrons. In order to prevent overheating of the reflective electron blocking structure 160 , a cooling medium flows around the outer peripheral surface of the reflective electron blocking structure 160 . A cooling pipe 166 may be provided.

The cooling medium may be water or any other fluid advantageous for cooling.

Therefore, the reflective electron blocking structure 160 can be cooled, and since the cooling pipe 166 is provided around the outer peripheral surface of the reflective electron blocking structure 160, even if a leak occurs in the cooling pipe 166 Since the leaked cooling medium leaks between the tube 152 and the reflective electron blocking structure 160 , it can be prevented from leaking out of the electron beam emitting device through the anode 130 and the emission port 156 .

In addition, a blocking plate 168 is further provided on the outside of the cooling pipe 166 to prevent the reflected electrons from being directly irradiated to the cooling pipe 166 to prevent damage to the cooling pipe 166 in advance. .

As described above, when the electron beam emitting device 100 of the plasma continuous electron beam method is used, the electron beam can be continuously irradiated, so that steady heating is possible, the diameter of the electron beam is small, and the irradiation point can be adjusted more precisely, and the focusing rate It is possible to control the heating intensively or as a whole at the required point because the control of the and diffusivity is free.

In addition, in the case of brazing, the filler 16 may be evaporated and gasified. In the case of the plasma method, the required vacuum degree is relatively low, so there is little risk of problems caused by gas.

In addition, when a hot electron beam type electron beam emission device is applied as the electron beam emission device 100, an electric field is generated when irradiating an electron beam to a non-conductive material such as a ceramic material, so it may be difficult to work, but as in this embodiment, the plasma electron beam When the electron beam emitting device 100 of the method is applied, the generation of an electric field is suppressed by the neutralization action by plasma, and thus, there is an advantage that it can be applied to a non-conductive material.

Of course, the electron beam emission apparatus 100 of the present invention is not limited to the above-described plasma electron beam method, and other various types of electron beam emission apparatus may be applied.

On the other hand, in the chamber 210, the first base material 12 and the second base material 14, which are brazed to each other, and the filler 16 positioned between the first base material 12 and the second base material 14 are It is a component that forms the space in which it is located.

Also, the electron beam irradiated from the electron beam emitting device 100 in communication with the electron beam emitting device 100 may be irradiated to the bonding object 10 positioned inside the chamber.

Hereinafter, the first base material 12 , the second base material 14 , and the filler 16 will be referred to as a bonding object 10 .

The first base material 12 of the bonding object may be an electrically conductive material through which electricity passes.

In addition, the second base material 14 may be a non-conductive material that does not conduct electricity.

On the other hand, in the description of the present embodiment, the object 10 to be joined is an insert tip cutting tool used for a cutting operation, etc. as an example. Of course, the joint object 10 of the present invention is not necessarily limited to the insert tip cutting tool, and may be other.

In this embodiment, as a material of the first base material 12, a steel-based alloy such as steel or stainless steel, tool steel or high-speed steel will be exemplified.

In addition, as the material of the second base material 14, stainless carbide (WC) will be described as an example, but the present invention is not necessarily limited thereto, and various ceramic materials such as Al2O3, SiC, CBN, PCD, etc. may be applied. .

On the other hand, as the filler 16 for bonding the first base material 12 and the second base material 14, a nickel-based alloy material or nickel and cobalt may be used, or a silver-based alloy material or silver may be used. Various materials may be applied.

Nickel and nickel-based alloy materials have a high melting point, but have excellent bonding strength and heat resistance temperature, and excellent internal damping properties, so that the impact applied to the second base material 14 can be effectively absorbed, and the strength decreases due to the increase in temperature. phenomena can be ruled out.

At this time, since the material of nickel or cobalt has a high brazing temperature, it can be applied by pairing with a ceramic material such as WC or Al2O3, SiC, CBN, which has excellent high temperature heat resistance, and the silver-based material has a brazing temperature of nickel or cobalt. It can be applied in combination with a ceramic material such as PCD because it is relatively low compared to the material.

On the other hand, as shown in FIGS. 4 and 5 , the first base material 12 of the bonding object 10 is located on the surface of the bonding object 10 located inside the chamber 210 and is applied by an applied current. An induction coil 230 for heating may be provided.

The induction coil 230 may be disposed on the surface of the bonding object 10 to receive alternating current, and may be provided to inductively heat the first base material 12 made of an electrically conductive material.

In addition, the electron beam e irradiated from the electron beam emitting device 100 is irradiated to the second base material 14 or the filler 16 of the bonding object 10 to the second base material 14 or the filler 16 . can be heated.

That is, the first base material 12 made of an electrically conductive material is induction heated by the induction coil 230 , and the second base material 14 made of a non-conductive material is an electron beam irradiated from the electron beam projection device 100 . It may be provided to be heated by (e).

Accordingly, the first base material 12 and the second base material 14 may be heated independently of each other.

Also, the filler 16 may be induction heated by the induction coil 230 or may be heated by the electron beam e irradiated from the electron beam emitting device 100 . Of course, it may be heated by heat conducted from the first base material 12 or the second base material 14 .

In this case, the induction coil 230 may be positioned on the surface of the first base material 12 or the second base material 14 of the bonding object 10 .

When the induction coil 12 is positioned on the surface of the second base material 14, the induction coil 230 serves to ground the second base material 14 of the non-conductive material, so that the second base material 14 ) can be prevented from charging on the surface.

The charging phenomenon may mean a phenomenon in which electrons are accumulated on the surface of an electron beam irradiation surface due to continuous electron beam irradiation when an electron beam is irradiated to a non-conductive material. When such a charging phenomenon occurs, the electron beam is distorted by the repulsive force of electrons charged on the surface of the non-conductive material, so that precise irradiation of the electron beam may be impossible.

Therefore, when the induction coil 230 made of a material through which electricity flows is in contact with the second base material 14 made of a non-conductive material such as tungsten carbide (WC), the ground is made by the electrically conductive induction coil 230. Since the electron charging phenomenon does not occur, the heating of the second base material 14 made of a non-conductive material can be performed.

Also, as shown in FIG. 6 , the induction coil 230 may be formed to have a cross section of a hollow 231 so that coolant flows therein. Therefore, even when the induction coil 230 is heated by the irradiated electron beam, the cooling water can cool the induction coil 230, thereby preventing overheating.

Of course, the present invention is not limited thereto, and the induction coil 230 may be formed such that it does not contact the second base material 14 but only the first base material 12 .

In this case, as shown in FIG. 7 , in order to solve the charging phenomenon caused by electron beam irradiation on the surface of the second base material 14 , the conductive piece 292 formed of a conductive material is applied to the second base material of a non-conductive material. (14) The conductive layer 290 may be formed by positioning it to be in contact with the surface.

The conductive piece 292 may be formed of a material having excellent conductivity and heat transfer properties, such as copper.

In addition, the conductive piece 292 may be grounded through a ground wire 294 .

That is, since the conductive piece 292 is grounded, the charging phenomenon of electrons does not occur, and when the electron beam is irradiated to the conductive piece 292 and heat is generated, since it is in contact with the second base material 14 made of a non-conductive material, heat transfer The brazing process of the second base material 14 made of a non-conductive material may be performed by this.

In addition, the carbon nanotube solution 296 may be used instead of the conductive piece 292 .

As shown in FIG. 8 , the carbon nanotube solution 296 may be a solution in which carbon nanotubes are dispersed in isopropyl alcohol (IPA) or water.

The carbon nanotube solution 296 may be applied to the surface of the bonding object 10, or the bonding object 10 may be immersed in the carbon nanotube solution and then taken out.

Then, the bonding object 10 to which the carbon nanotube solution 296 is applied may be dried.

When drying, the bonding object 10 may be placed in the chamber 210 and then heated through the heating unit 310 or a vacuum atmosphere may be formed in the chamber 210 by using the vacuum discharge pump 270 .

When a vacuum atmosphere is formed in the chamber 210, the solvent in the coated carbon nanotube solution evaporates and only the carbon nanotube remains, and the evaporated solvent is discharged to the outside of the chamber 210 through the vacuum discharge pump 270, , the remaining carbon nanotubes may form a conductive layer 293 on the surface of the bonding object 10 .

In addition, as the bonding object 10 is fixed to the stage 220, the conductive layer 293 and the stage 220 are connected, and the stage 220 is also formed of a conductive material and grounded, so that the bonding object 10 is The conductive layer 293 of the carbon nanotube remaining on the surface is also grounded.

In addition, the chamber 210 is provided with an openable and openable door 212 so that the bonding object 10 can be carried in or taken out into the chamber 210 .

Meanwhile, the stage 220 is provided inside the chamber 210 , and may be provided to fix the bonding object 10 carried into the chamber 210 .

The stage 220 is a component on which the bonding object 10 is seated or fixed, as shown in FIG. 3 .

At this time, the stage 220 may be moved in the horizontal direction to horizontally transport the bonding object 10 .

In addition, the cooling unit 240 may be a component that cools the stage 220 . In order to cool the stage 220, the cooling unit 240 includes a tank in which a cooling medium is stored, a pipe 242 through which the cooling water of the tank flows to the stage, and a pump 244 that pressurizes the cooling medium and adjusts the circulation amount. ) and the like. In this case, the cooling medium may be a fluid such as water, oil, or air or gas.

In this case, in order to cool the stage 220 , the pipe 242 may be buried inside the stage.

The stage 220 may also be made of a material having high thermal conductivity, and may be formed such that the joint object 10 in contact with the stage 220 and the joint break occur.

Accordingly, the cooling unit 240 may cool the stage 220 and simultaneously cool the bonding object 10 in contact with the stage 220 .

Of course, if necessary, the stage 220 may not be installed, may be omitted, or may be replaced with other structures.

Meanwhile, a control unit 280 for controlling the electron beam emitting device 100 , the stage 220 , the cooling unit 240 , and the induction coil 230 may be provided.

The control unit 280 may be composed of an arithmetic unit, an input unit, an output unit, etc. which are integrally provided in the electron beam brazing apparatus of this embodiment, or are separately provided outside, and the electron beam emitting apparatus 100 and the stage 220 by wire or wireless. , the cooling unit 240 and the induction coil 230 may be connected and controlled by a PC or the like.

That is, in the control unit 280, the electron beam irradiated from the electron beam emitting device 100 heats the second base material 14 or the filler 16 of the bonding object 10, and the induction coil It can be controlled to heat the first base material 12 of the object 10 . That is, by controlling the electron beam emitting device 100 and the induction coil 230 according to the control of the controller 280, the heating point, the heating object, and the heating temperature can be controlled.

On the other hand, the volume of the first base material 12 and the second base material 14 is expanded according to the intrinsic coefficient of thermal expansion while being heated, and may be contracted according to the intrinsic coefficient of thermal expansion of the material even when cooled.

However, since the first base material 12 and the second base material 14 are different materials, the coefficients of thermal expansion may be different from each other, and accordingly, when the same amount of heat is applied, different amounts of thermal expansion and thermal contraction may be exhibited.

If the first base material 12 and the second base material 14 in the mutually bonded state exhibit different amounts of thermal expansion and thermal contraction, stress may be applied to lead to cracks.

Therefore, when the first base material 12 and the second base material 14 are heated, the control unit 280 may heat to exhibit the same amount of thermal expansion per unit time. In addition, when the first base material 12 and the second base material 14 are cooled, they may be cooled to exhibit the same amount of heat shrinkage per unit time.

Therefore, since the first base material 12 and the second base material 14 are heated so that the same amount of thermal expansion per unit time is equal to each other, or cooled so that the amount of thermal contraction per unit time is equal to each other, the first base material 12 and the second base material which are different from each other are different materials. 2 The generation of cracks in the base material 14 can be prevented.

In addition, an infrared camera 260 for measuring the temperature of the bonding object 10 located inside the chamber 210 or taking an image may be provided.

The infrared camera 260 may take a thermal image of the bonding object 10 and transmit it to the control unit 280 , and the control unit 280 may transmit the thermal image information of the infrared camera 260 to the bonding object. It is possible to grasp the temperature for each part of the PC and display it on the screen of the PC. Based on the data received from the infrared camera 260 and the previously input data such as material quality, shape, and brazing working conditions, the electron beam emitting device 100 ), the stage 220 and the cooling unit 240 can be controlled.

Of course, in addition to the infrared camera 260, a measuring device such as a separate camera for measuring the shape and size of the bonding object 10 may be provided.

In addition, a vacuum discharge pump 270 for controlling the degree of vacuum by discharging the gas inside the chamber 210 , and a gas supply unit 250 for supplying a reaction gas to the inside of the chamber 210 may be provided. The reaction gas is input during brazing, and various gases such as Ar or H2 may be applied as a gas for more smoothly inducing brazing bonding. Such a reaction gas may be appropriately selected according to the type of the first base material 12, the second base material 14, and the filler 16, and brazing operation conditions.

Meanwhile, the electron beam brazing apparatus of this embodiment may further include an atmosphere cooling unit 320 .

Immediately after brazing is performed using the electron beam, not only the base material and the filler irradiated with the electron beam, but also the ambient air inside the chamber 210 may be heated to a very hot temperature.

Therefore, the heated portion of the base material and filler in a high-temperature state may react with oxygen contained in the high-temperature ambient air to cause oxidation.

Therefore, the atmosphere cooling unit 320 may be provided to cool the air in the chamber 210 after the irradiation of the electron beam is finished or during the irradiation with the electron beam to prevent oxidation of the base material and filler in a high temperature state and to promote cooling. .

The atmosphere cooling unit 320 as described above may be installed outside the chamber 210 so that a part of the cooler or heat exchanger is located inside the chamber 210 to cool the air inside the chamber 210 . there is. Of course, the present invention is not limited thereto, and may be made to cool the air inside the chamber 210 in other forms, such as cooling the wall itself of the chamber 210 .

In addition, the electron beam brazing apparatus of this embodiment may further include an atmosphere heating unit 310 .

As shown in FIG. 10 , the trend in which the temperature rises with time when the base material is heated does not draw a linear graph of a straight line, but may represent an exponential graph in which the rise increases over time.

Also, as shown in FIG. 10 , it can be seen that the higher the initial preheating temperature, the higher the temperature after the same heating time has elapsed.

Therefore, by maximally raising the preheating temperature before electron beam irradiation, the time of the brazing process can be shortened and the amount of energy required can be saved.

Therefore, the atmosphere heating unit 310 may increase the temperature in the chamber 210 to increase the temperature of the base material 10 to a set temperature.

The atmosphere heating unit 310 as described above is installed outside the chamber 210, and a part of the heat exchanger or heater is located inside the chamber to heat the atmosphere (gas, etc.) inside the chamber 210. can

Of course, the atmosphere heating unit 310 may be provided to directly heat the bonding object 10 . Of course, the atmosphere heating unit 310 of the present invention is not limited to its shape or structure, and if the atmosphere inside the chamber 210 or the bonding object 10 can be preheated, it can be modified into any shape or structure. .

On the other hand, most of the electron beam emitted from the electron beam emitting device 100 is controlled to be irradiated to the bonding object 10 , but a part of the electron beam irradiated to a place outside the bonding object 10 may be generated.

This leakage electron beam is the cause of not being able to heat the bonding object 10 as much as initially intended, and a separate structure such as a wall surface of the chamber 210 or a base material moving means (not shown) located below the bonding object 10 is intended. Overheating may cause deformation.

Accordingly, an insulator 330 that blocks such a leakage electron beam may be provided.

The insulator 330 is located below the portion where the base material 10 is located inside the chamber 210 so that the leakage electron beam is located on the wall of the chamber 210 or a separate structure located below the base material 10 . It can block heating.

In addition, the insulator 330 may be grounded 334 to prevent electrons from accumulating due to the leakage electron beam, and an ammeter 332 may be connected to measure the amount of the electron beam irradiated to the insulator 330 .

Therefore, the control unit 280 compares the current value of the electron beam emitted from the electron beam emitting device 100 with the current value measured by the ammeter 332 connected to the insulator 330 to be irradiated to the base material 10 . The current value can be estimated, and through this, the electron beam emitted from the electron beam emitting apparatus 100 can be more precisely feedback-controlled.

In addition, the wall surface of the chamber 210 may be insulated.

Hereinafter, an embodiment of a method of controlling a dissimilar material brazing apparatus using an induction coil and an electron beam according to another aspect of the present invention will be described.

As shown in FIG. 9, the control method of the dissimilar material brazing apparatus according to this embodiment includes a preheating step (S110), an induced current heating step (S120), an electron beam irradiation step (S130) and a cooling step (S140). can

The preheating step (S110) is a step of increasing the temperature in the chamber 210 by using the heating unit 310 or the like. In this step, the bonding object 10 may be directly heated or the ambient temperature in the chamber 210 may be increased. In addition, since the ambient temperature in the chamber 210 is increased, the temperature of the bonding object 10 located in the chamber 210 may also be increased through heat conduction.

As shown in FIG. 10 , it can be seen that the temperature rise increases exponentially as the initial preheating temperature is higher even when heated for the same time. It can shorten the time and save the amount of energy required for the brazing process.

In addition, when manufacturing a cutting tool such as an insert tip, the cutting layer corresponding to the second base material 14 uses ceramics (tungsten carbide, aluminum oxide, PCD, CBN) to improve wear resistance, but the In this case, if the material is heated at high temperature for a long time, a grain-growth phenomenon occurs in which crystals of the material grow, resulting in reduced wear resistance or reduced mechanical strength. can be This is not a phenomenon that only occurs in the second base material 14, but may also occur in the first base material 12 formed of a metal material.

Therefore, in this embodiment, by preheating the temperature of the bonding object 10 in advance, the heating time to a high temperature can be significantly shortened, thereby preventing the crystal grain growth of the first base material 12 and the second base material 14 . or can be minimized.

After the preheating step (S110), an induced current heating step (S120) and an electron beam irradiation step (S130) may be formed.

The induction current heating step (S120) is a step of heating the first base material 12 by induction heating by applying an alternating current to the induction coil 230 .

In addition, the electron beam irradiation step ( S130 ) is a step of heating the second base material 14 by irradiating an electron beam to the second base material 14 through the electron beam emitting device 100 .

In the induced current heating step ( S120 ) and the electron beam irradiation step ( S130 ), the first base material 12 and the second base material 14 may be each independently heated.

At this time, the first base material 12 and the second base material 14 may be heated so that the amount of thermal expansion per unit time is the same.

That is, since the first base material 12 is heated by the induction coil 230 and the second base material 14 is heated by the electron beam emitting device 100, it can be independently heated by different heat sources. Therefore, the amount of heating and the heating temperature may be different from each other, and it may be relatively easy to heat the first base material 12 and the second base material 14 so that the amount of thermal expansion is the same.

In addition, the first base material 12 and the second base material 14 may be heated until the filler 16 is melted through the induced current heating step (S120) and the electron beam irradiation step (S130).

Meanwhile, gas may be injected into the chamber 210 during the induced current heating step ( S120 ) and the electron beam irradiation step ( S130 ).

In general, the plasma electron beam method can operate in a relatively low vacuum environment, so that the brazing effect can be further improved by injecting a gas that creates a brazing environment.

After the induced current heating step (S120) and the electron beam irradiation step (S130), a cooling step (S140) may be further performed. In the cooling step ( S140 ), the first base material 12 and the second base material 14 are joined by the filler 16 by cooling and solidifying the molten filler 16 .

At this time, even in the cooling step (S140), by heating the first base material 12 and the second base material 14 with the induction coil 230 or the electron beam emitting device 100, the first base material 12 and When the second base material 14 is cooled, it is possible to control the amount of heat shrinkage per unit time to be the same.

That is, as shown in FIG. 12, when the first base material 12 and the second base material 14 in a heated state are cooled in the same manner, even if the temperature is the same, the first base material 12 and the second base material 14 may have different amounts of heat shrinkage due to a difference in heat shrinkage rates.

Due to the difference in the amount of heat shrinkage, the joint between the first base material 12 and the second base material 14 may be damaged or distorted during cooling.

Therefore, in this embodiment, as shown in FIGS. 13 and 14, in the cooling step, the amount of heat shrinkage per unit time of the first base material 12 and the second base material 14 can be the same or as similar as possible. .

At this time, the first base material 12 or the second base material 14 or the first base material 12 and the second base material so that the heat shrinkage per unit time of the first base material 12 and the second base material 14 is the same. (14) All of them can be irradiated intermittently or continuously through the induction coil or the electron beam emitting device to independently control the cooling rate and cooling amount.

That is, if the first base material 12 is a material having a heat shrinkage rate of 1/5 lower than that of the second base material 14 (that is, the heat shrinkage rate of the second base material 14 is 5 times greater than that of the first base material 12 ) surface), by continuously or intermittently irradiating the electron beam (e) to the rapidly shrinking second base material 14 to control the amount of heat shrinkage equal to or similar to that of the first base material 12 .

14 shows the first base material 12 and the second base material 14 having a low heat shrinkage rate of the second base material 14 is continuously cooled by a normal air cooling or water cooling method, and the first base material 12 having a high heat shrinkage rate. Like the second base material 14, it is intermittently heated during continuous cooling by air cooling or water cooling method, and shows a graph in which the amount of heat shrinkage during cooling is controlled to be similar to that of the second base material 14.

That is, while cooling, the amount of heat shrinkage during cooling by continuous or intermittent heating can be controlled so that the first base material 12 and the second base material 14 are the same or similar to each other.

Meanwhile, in order to further increase the cooling rate during cooling, the cooling unit 240 may be used.

By circulating a cooling medium in the pipe 242 in the cooling unit 240 described above, the stage is cooled, and thus the bonding object 10 in contact with the stage 220 can be cooled.

Therefore, while the bonding object 10 is cooled by the cooling unit 240, it is heated intermittently or continuously by induction heating by the induction coil and electron beam irradiation to reduce the amount of heat shrinkage during cooling with the first base material 12 and the first base material 12. It is possible to control the two base materials 14 to be similar to each other.

At this time, the cooling rate may be controlled by adjusting the circulation amount of the cooling medium or adjusting the temperature of the cooling medium. Of course, in this case, a separate temperature control unit (not shown) for controlling the temperature of the cooling medium may be provided.

In addition, the atmosphere inside the chamber 210 may also be cooled. By cooling the temperature of the atmosphere in the chamber 210, it is possible to prevent oxidation by reacting the first and second base materials heated to a high temperature with ambient air.

Meanwhile, during the process, the temperature of each part of the bonding object 10 is measured with the infrared camera 260 so that the temperature of each part of the first base material 12 or the second base material 14 is uniform or It is possible to control the electron beam emitting device 100 , the induction coil 230 , and the cooling unit 240 by measuring whether or not it approaches a set value and feedback-controlling it.

As described above, the preferred embodiments according to the present invention have been described, and the fact that the present invention can be embodied in other specific forms without departing from the spirit or scope of the present invention other than the above-described embodiments is a fact having ordinary skill in the art. It is obvious to them. Therefore, the above-described embodiments are to be regarded as illustrative rather than restrictive, and accordingly, the present invention is not limited to the above description, but may be modified within the scope of the appended claims and their equivalents.

10: work object 12: first base material
14: second base material 16: filler
100: electron beam emitter 120: cathode
122: Rounded part of the cathode rim
130: anode 132: opening
140: insulation holder 150: housing
152: tube 154: insulator
156: outlet 158: ground
160: reflective electron blocking structure 162: flange portion
164: absorption groove 166: cooling pipe
168: blocking plate 210: chamber
212: door 220: stage
230: induction coil 240: cooling unit
242: pipe 244: pump
250: gas supply unit 260: infrared camera
270: vacuum discharge pump S110: preheating step
S120: induced current heating step S130: electron beam irradiation step
S140: cooling stage
e: electron beam

Claims (13)

an electron beam emitting device including a cathode and an anode;
a chamber in which an electron beam emitted from the electron beam emitting device is irradiated and a bonding object including a first base material of an electrically conductive material and a second base material of a non-conductive material to be bonded to each other is positioned;
an induction coil positioned on the surface of the bonding object and heating the first base material of the bonding object by induction heating by an applied current;
The electron beam irradiated from the electron beam emitting device heats the second base material of the joining object, and controls the induction coil to heat the first base material of the joining object, thereby heating the first base material and the second base material from different heating sources. a control unit for heating independently of each other;
A dissimilar material brazing device comprising a. According to claim 1,
The control unit is
A dissimilar material brazing device for controlling the amount of thermal expansion per unit time of the first base material and the second base material to be the same. According to claim 1,
The control unit is
A dissimilar material brazing device for controlling the amount of heat shrinkage per unit time of the first base material and the second base material to be the same. According to claim 1,
The induction coil is a dissimilar material brazing device positioned on the surface of the second base material of the bonding object. According to claim 1,
The induction coil is a dissimilar material brazing device located on the surface of the first base material of the bonding object. According to claim 1,
The induction coil is a heterogeneous material brazing device formed to have a hollow cross section so that the coolant flows therein. According to claim 1,
a conductive layer connected to the surface to which the electron beam of the second base material of the bonding object is irradiated to cover the second base material; and
a ground wire for grounding the conductive layer;
A brazing device of heterogeneous material comprising a. In a method of controlling a dissimilar material brazing device for placing a filler between a first base material of an electrically conductive material and a second base material of a non-conductive material, heating it to melt the filler, and bonding the first base material and the second base material ,
Induction current heating step of heating the first base material by operating the induction coil;
an electron beam irradiation step of heating the second base material with an electron beam;
including,
A control method of a dissimilar material brazing apparatus for independently heating the first base material and the second base material as different heating sources. 9. The method of claim 8,
The induced current heating step and the electron beam irradiation step are,
A control method of a dissimilar material brazing device for heating the first base material and the second base material to have the same amount of thermal expansion per time. 9. The method of claim 8,
After the bonding of the first base material and the second base material is completed,
A control method of a dissimilar material brazing device further comprising a cooling step of cooling the first base material and the second base material. 11. The method of claim 10,
The cooling step is
A control method of a heterogeneous material brazing device for controlling the induction coil and the electron beam so that the heat shrinkage rate per time of the first base material and the second base material are the same. 9. The method of claim 8,
Before the induced current heating step and the electron beam irradiation step, the control method of the dissimilar material brazing apparatus further comprising a preheating step of preheating the temperature of the first base material and the second base material to a preset temperature. 13. The method of claim 12,
The preheating step is a control method of a dissimilar material brazing device, which is a step of raising the temperature of the first base material and the second base material by raising the ambient temperature inside the chamber.

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