Brazing material, bonded body, method for manufacturing brazing material, and method for manufacturing bonded body

Abstract

A brazing material including Cu; Mg; at least one first element selected from the group consisting of Sn, Sb, and Bi; and at least one second element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, Ca, Ce, La, Sm, Yb, Nd, Gd, and Er.

Description

Technical Field

[0001] This disclosure relates to brazing materials, joints, methods for manufacturing brazing materials, and methods for manufacturing joints. Background Technology

[0002] The joint formed by joining a metal component, such as copper, with a ceramic material can be used as a constituent material for an electric control device installed in an electric or hybrid vehicle. Techniques using active metal brazing materials containing silver (Ag) to join metal components and ceramic materials are known. In recent years, to address issues such as Ag migration and high cost, techniques have been proposed that use materials containing an active metal with no Ag as the main phase for joining (see, for example, Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: JP 2018-140929 A Summary of the Invention

[0006] The problem the invention aims to solve

[0007] The purpose of this disclosure is to provide a technique for improving the bonding strength of a joint by using an active metal brazing material that does not contain Ag as the main phase.

[0008] Solution for solving the problem

[0009] According to one aspect of this disclosure, a brazing material is provided, comprising:

[0010] Cu;

[0011] Mg;

[0012] Choose at least one first element from the group consisting of Sn, Sb, and Bi, and

[0013] It is selected from at least one second element in the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, Ca, Ce, La, Sm, Yb, Nd, Gd and Er.

[0014] According to another aspect of this disclosure, a joint is provided, comprising:

[0015] The first component is made of metal;

[0016] A second component that joins with the first component and is made of the same or different metal or ceramic as the first component; and

[0017] The bonding layer on the joint surface of the first component and the second component,

[0018] The bonding layer includes:

[0019] Cu;

[0020] Mg;

[0021] Choose at least one first element from the group consisting of Sn, Sb and Bi;

[0022] And at least one second element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, Ca, Ce, La, Sm, Yb, Nd, Gd and Er.

[0023] According to other aspects of this disclosure, a method for manufacturing a brazing material is provided, which is a method for manufacturing a brazing material for joining metal components and ceramic components, the brazing material comprising at least one first element selected from the group consisting of Cu, Mg, Sn, Sb and Bi, and at least one second element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, Ca, Ce, La, Sm, Yb, Nd, Gd and Er.

[0024] According to other aspects of this disclosure, a method for manufacturing an assembly is provided, comprising:

[0025] In the configuration process, a first component made of metal and a second component made of the same or different metal or ceramic as the first component are stacked together in a manner separated by brazing material; and

[0026] The heating process involves applying pressure in the lamination direction while heating and maintaining the laminate of the first and second components.

[0027] The material comprising at least one first element selected from the group consisting of Cu, Mg, Sn, Sb and Bi, and at least one second element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, Ca, Ce, La, Sm, Yb, Nd, Gd and Er is used as a brazing material.

[0028] The effects of the invention

[0029] According to this disclosure, the bonding strength of the joint can be improved. Attached Figure Description

[0030] [ Figure 1 ] Figure 1 This is a partial cross-sectional view of a metal / ceramic joint 100 according to one embodiment of the present disclosure.

[0031] [ Figure 2 ] Figure 2 yes Figure 1 A magnified view of the area A within the dashed line.

[0032] [ Figure 3 ] Figure 3 (a) is a schematic diagram showing the shear stress applied to the bonding layer 30, and Figure 3 (b) is a schematic diagram showing the tensile stress applied to the bonding layer 30.

[0033] [ Figure 4 The following are the details: Figure 4 (a) shows the state in which the metal component 10 and the ceramic component 20 are arranged with brazing material 50 in between; Figure 4 (b) shows the state in which the laminate of metal component 10 and ceramic component 20 is heated while under pressure; and Figure 4 (c) shows the manufactured metal / ceramic joint 100.

[0034] [ Figure 5 ] Figure 5 This is a schematic diagram showing the state when a shear strength test is performed.

[0035] [ Figure 6 ] Figure 6 This is a magnified image of a portion of the cross-section of the bonding layer of sample 1.

[0036] [ Figure 7 ] Figure 7 This is a magnified image of a portion of the cross-section of the bonding layer of sample 8.

[0037] [ Figure 8 ] Figure 8 This is a magnified image of a portion of the cross-section of the bonding layer of sample 15. Detailed Implementation

[0038] Brazing materials not only need to avoid significantly altering the microstructure of the materials being joined during heating, but also require the resulting bond layer to be strong and tough. The inventors have discovered that a Cu-Mg eutectic composition that can significantly lower the melting point of Cu is suitable as a composition for an active metal brazing material that meets the above requirements.

[0039] However, in the Cu-Mg binary eutectic composition, Mg has a high vapor pressure, and it is known that evaporation occurs rapidly at temperatures above 600°C when Mg is added alone, and at temperatures above 780°C when Mg is added as MgCu2. The bonding temperature that can be used with brazing materials is 720°C, which is the Cu-Mg eutectic point where the liquid phase begins to form. However, considering factors such as the wettability of the liquid phase, higher temperatures are required, which tends to make Mg evaporate more easily. Therefore, there is a possibility of voids forming due to Mg evaporation before a strong bond microstructure can be formed, and bond layers containing such voids tend to have low bond strength. Furthermore, if excessive Mg is added, bonding can occur before Mg evaporates, but this forms a large number of intermetallic compounds such as MgCu2 and CuMg2, which are known to be brittle, and tend to be difficult to maintain high bond strength. Therefore, although the melting temperature of the Cu-Mg binary eutectic composition can be significantly reduced, there are still many factors that reduce bond strength, making it difficult to achieve high-strength bonding.

[0040] The inventors have investigated methods to suppress the evaporation of Mg in Cu-Mg eutectic compositions and designed elements that, when combined with Mg, form compounds with melting points higher than Mg, and simultaneously form eutectic reactions with each of Cu and Mg, or with Cu and Mg in a ternary eutectic system. Elements that induce such eutectic reactions, the inventors have focused on, for example, silicon (Si), germanium (Ge), tin (Sn), phosphorus (P), arsenic (As), antimony (Sb), and bismuth (Bi).

[0041] Therefore, the inventors added the aforementioned elements to Cu-Mg based active metal brazing materials and studied the resulting bonding layers. As a result, the inventors found that among the aforementioned elements, Sn, Sb, and Bi increased the bonding strength, while Si, Ge, P, and As did not sufficiently increase the bonding strength. Further research on this point revealed that, compared to Mg, Si and others tend to react more readily with the aforementioned active metal elements, thus failing to achieve the expected effect of reacting with Mg and inhibiting its evaporation.

[0042] Based on these findings, the inventors have discovered that, in order to suppress the decrease in bonding strength caused by the evaporation of Mg in Cu-Mg-based active metal brazing materials, it is effective to add Sn, Sb, and Bi as Mg evaporation suppressing elements, which react with Mg to form compounds with melting points higher than those of Mg.

[0043] This invention is based on the above findings.

[0044] <One implementation of this disclosure>

[0045] An embodiment of this disclosure will be described with reference to the foregoing accompanying drawings. The drawings used in the following description are schematic. The dimensions and scales of the elements shown in the drawings do not necessarily correspond to their actual dimensions. Furthermore, the dimensions and scales of elements in the drawings do not necessarily match between figures. Additionally, in this specification, the use of the term "to" to indicate a range that includes the values ​​before and after "to" as a lower and upper limit.

[0046] (1) Brazing materials

[0047] The brazing material of this embodiment is a Cu-Mg based active metal brazing material containing Cu as the main component (primarily Cu, with Mg as an essential component) (e.g., 50 at.% or more Cu). Specifically, the brazing material contains Cu, Mg, at least one first element selected from the group consisting of Sn, Sb, and Bi (hereinafter also referred to as "Mg evaporation inhibiting element"), and at least one second element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, Ca, Ce, La, Sm, Yb, Nd, Gd, and Er (hereinafter also referred to as "active metal element"). The brazing material preferably contains Mg, Mg evaporation inhibiting element, active metal element, and unavoidable impurities, with the remainder being Cu. Furthermore, the absence of Ag further improves the migration resistance of the brazing material. The brazing material can be used to bond metal components to ceramic components, or to bond two metal components together. Unavoidable impurities are elements other than those intentionally added during the preparation of the brazing material, such as elements derived from the raw materials.

[0048] When the brazing material is heated for bonding, Cu is the element that forms the solid solution that mainly constitutes the bonding layer, and Cu also contributes to the ductility and malleability of the bonding layer.

[0049] Mg lowers the melting point of Cu, thereby reducing the bonding temperature of the brazing material, and also increases the wettability of the brazing material on metal and ceramic components.

[0050] The Mg evaporation suppressant is an element that readily reacts with Mg when the brazing material is heated, and forms a compound with Mg through this reaction. This compound has a melting point higher than that of Mg and melts at the bonding temperature, forming a eutectic manner that suppresses the evaporation of molten components such as Mg. Therefore, the Mg evaporation suppressant reacts with Mg during bonding and can suppress Mg evaporation. Furthermore, when the brazing material is heated, the Mg evaporation suppressant forms a ternary intermetallic compound with Cu and Mg, and improves the strength of the intermetallic compound. As the Mg evaporation suppressant, at least one element selected from the group consisting of Sn, Sb, and Bi can be used. More preferably, at least one of Sn and Sb is always included as the Mg evaporation suppressant (excluding Bi alone), and even more preferably, the first element consists of at least one of Sn and Sb (excluding Bi).

[0051] When the brazing material is heated, the active metal element reacts with the ceramic component to form a compound, thereby increasing the bonding strength between the ceramic component and the bonding layer. For example, at least one active metal element selected from the group consisting of titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), chromium (Cr), molybdenum (Mo), tungsten (W), yttrium (Y), calcium (Ca), cerium (Ce), lanthanum (La), samarium (Sm), ytterbium (Yb), neodymium (Nd), gadolinium (Gd), and erbium (Er) can be used. When the ceramic component is Si3N4 or AlN, at least one active metal element selected from the group consisting of Ti, V, Nb, Cr, Mo, and Ca is preferred, with Ti being particularly preferred.

[0052] There are no particular restrictions on the content of each element. For example, the content of Cu is preferably 50 at.% or more and 95 at.% or less, more preferably 55 at.% or more and 80 at.% or less. The content of Mg is preferably 1 at.% or more and 15 at.% or less, more preferably 3 at.% or more and 12 at.% or less. The content of Mg evaporation inhibiting element is preferably 1 at.% or more and 20 at.% or less, more preferably 3 at.% or more and 15 at.% or less. The content of active metal element is preferably 0.1 at.% or more and 10 at.% or less, more preferably 1 at.% or more and 10 at.% or less. A portion of Cu can be replaced by other elements in the range of 1 at.% or less. Furthermore, when the content of Mg is X at.% and the content of Mg evaporation inhibiting element is Y at.%, it is preferable that X-6 ≤ Y ≤ X+6, more preferably that X-5 ≤ Y ≤ X+5. By including the elements within this content range, the desired bonding strength in the bonding layer can be obtained, while reducing the bonding temperature of the brazing material; therefore, these content ranges are preferred.

[0053] The form of the brazing material is not particularly limited and can be, for example, paste, foil, or wire. Of these, paste is preferred from the viewpoint of obtaining a uniform phase structure (described later) in the bonding layer. Paste-like brazing materials comprise powder containing the aforementioned elements. In the case of foil, quenching or rolling can be selected as the manufacturing method. In the case of wire, a general wire drawing method can be used.

[0054] In a paste-like brazing material, there are no particular restrictions on how the elements are added. Each element can be included as an elemental powder or as a compound powder containing the corresponding element. The methods of adding each element will be described below.

[0055] Mg can be added as a powder containing at least one of the following: elemental Mg, a Mg solid solution containing other elements, a compound with Cu (MgCu2), a compound with an active metal element, and a compound with a Mg evaporation suppressing element. Preferably, at least a portion of the Mg is added as a powder containing an intermetallic compound with a Mg evaporation suppressing element. For example, Mg can be added as an alloy powder consisting of Mg and an intermetallic compound containing Mg and a Mg evaporation suppressing element, or an alloy powder consisting of a Mg evaporation suppressing element and an intermetallic compound containing Mg and a Mg evaporation suppressing element. Alternatively, the above alloy powder can be mixed with at least one of Mg powder and Mg-Cu intermetallic compound powder, and the resulting mixture can be added. By pre-converting at least a portion of Mg into an intermetallic compound with a Mg evaporation suppressing element, Mg evaporation during the melting of the brazing material can be more reliably suppressed. Alloy powder does not refer to a mixture of powder containing one element and powder containing other elements, but rather to a powder in which each element is contained in an alloy form within a single particle. In addition, a solid solution containing other elements refers to a solid solution in which some of the constituent elements in the crystal lattice are replaced by other elements, or a solid solution in which other elements have entered the interstitial spaces in the crystal lattice.

[0056] The alloy powder may contain at least Mg and a Mg evaporation inhibiting element, and may further contain Cu. When the Mg evaporation inhibiting element is Sn, for example, Mg2Sn or Cu4MgSn can be used as the alloy powder. When the Mg evaporation inhibiting element is Sb, Mg3Sb2 and CuMgSb can be used. When the Mg evaporation inhibiting element is Bi, Mg3Bi2 and CuMgBi can be used.

[0057] Alloy powders can be prepared by mixing and melting Mg, Mg evaporation inhibitors, and Cu (if necessary), and then atomizing the molten mixture to form spherical powders containing all elements. Atomization methods can be selected from gas atomization, disk atomization, water atomization, and plasma atomization.

[0058] There is no particular limitation on the amount of alloy powder containing Mg and Mg evaporation inhibitors added. However, it is preferable to add the alloy powder in such a way that the Mg content derived from the alloy powder is 40% or more of the total Mg content contained in the brazing material. For example, when the alloy powder containing Mg and Mg evaporation inhibitors is used in combination with at least one of Mg metal powder, Mg-active metal alloy powder, and Mg-Cu intermetallic compound powder, the amount of alloy powder containing Mg and Mg evaporation inhibitors added can be adjusted so that the Mg content derived from the alloy powder containing Mg and Mg evaporation inhibitors accounts for 40% or more of the total Mg content in the brazing material. The amount of alloy powder added can be 100% of the total Mg content in the brazing material; that is, it is acceptable to add only the alloy powder. With this amount, Mg evaporation can be suppressed more reliably.

[0059] Cu can be added in the form of a powder containing at least one of the following: elemental Cu, a Cu solid solution containing other elements, an intermetallic compound with Mg (e.g., MgCu2, etc.), an intermetallic compound with Mg evaporation-inhibiting elements (e.g., Cu3Sn and Cu3Sb, etc.), an intermetallic compound with active metal elements (e.g., Cu-Ti compounds, such as Cu4Ti and Cu3Ti2, etc.), or an alloy containing elemental Cu, a solid solution, and an intermetallic compound with Cu.

[0060] Mg evaporation inhibitors can be added in the form of a powder containing at least one of the following: elemental form of Mg evaporation inhibitors, solid solutions containing other elements, compounds with at least one of Mg, Cu and active metal elements, or alloys containing Mg evaporation inhibitors, solid solutions and intermetallic compounds with Cu.

[0061] The active metal element can be added in the form of a powder containing at least one of the following: the elemental form of the active metal element, a solid solution containing other elements, a hydride, or an intermetallic compound formed with at least one of Mg, Cu, and Mg evaporation inhibitory elements.

[0062] There is no particular limitation on the amount of powder containing each element added. However, it is preferable that the brazing material contains each powder such that, for example, the content of Cu is 50 at.% or more and 80 at.% or less, the content of Mg is 1 at.% or more and 15 at.% or less, the content of the Mg evaporation inhibitor is 1 at.% or more and 20 at.% or less, and the content of the active metal element is 0.1 at.% or more and 10 at.% or less. By setting the content of each element within the above range, the effect of reducing the bonding temperature due to Mg and suppressing the evaporation of Mg using the Mg evaporation inhibitor can be achieved more reliably.

[0063] In brazing materials, the particle size of each powder containing Cu, Mg, Mg evaporation-inhibiting elements, and active metal elements can be appropriately selected based on the size of the materials being bonded and the thickness of the bonding layer. For example, in the case of large structures such as heat exchangers and hermetic seals, relatively large particle sizes can be used, and it is preferable that the average particle size D50 is 45 μm or more and 150 μm or less. Furthermore, for example, when the purpose is to reduce the thermal resistance of the bonded material such as a circuit board, it is desirable to form a thin bonding layer with a lower thermal conductivity compared to pure metals. In this case, it is preferable that the average particle size D50 is 45 μm or less. On the other hand, although there is no particular lower limit to the average particle size, it is preferable that the average particle size D50 is 5 μm or more in order to suppress the effect of surface oxidation of the powder. The average particle size D50 can be determined using, for example, a laser diffraction particle size distribution measurement device.

[0064] For brazing materials, the metal powder can be used in a paste form as needed, and in addition to the metal powder, it may also contain binders, solvents, surfactants, plasticizers, and dispersants. Examples of binders include polyvinyl alcohol, ethyl cellulose, polymethyl methacrylate, and polyacrylic acid derivatives. Examples of solvents include alcohols such as terpineol and butanediol, and toluene derivatives. Examples of surfactants include cationic surfactants, anionic surfactants, and nonionic surfactants.

[0065] There are no particular restrictions on the preparation method of brazing materials, and any conventional and well-known method can be used.

[0066] (2). Joint

[0067] Next, refer to Figure 1 Describing the joint. This embodiment illustrates an example of a joint (hereinafter also referred to as a metal / ceramic joint) in which a metal component (first component) and a ceramic component (second component) are joined together. Figure 1 This is a partial cross-sectional view of a metal / ceramic joint according to one embodiment of the present disclosure.

[0068] like Figure 1As shown, the metal / ceramic joint 100 includes: a metal component 10, a ceramic component 20 joined to the metal component 10, and a bonding layer 30 formed on the bonding surfaces of the metal component 10 and the ceramic component 20.

[0069] (Metal components)

[0070] Metal component 10 is made of pure copper, copper alloys, pure nickel, nickel alloys, titanium alloys, stainless steel (SUS), chromium alloys, iron alloys, cobalt alloys, and molybdenum alloys. For example, oxygen-free copper, tough-pitch copper, and phosphorus-deoxidized copper can be used as pure copper. As copper alloys, alloys containing copper (Cu) as the main element and at least one element selected from the group consisting of zinc (Zn), tin (Sn), phosphorus (P), aluminum (Al), beryllium (Be), cobalt (Co), nickel (Ni), iron (Fe), and manganese (Mn) can be used. As iron alloys, Invar (registered trademark), Kovar (registered trademark), high-speed steel, and mold steel can be used.

[0071] There are no particular limitations on the shape or size of the metal component 10, but when the metal / ceramic joint 100 is used as a constituent material of the insulating circuit board, it can be, for example, a flat plate with a thickness of more than 0.1 mm and less than 6.0 mm.

[0072] (Ceramic components)

[0073] The ceramic component 20 may contain at least one of, for example, nitrides, carbides, and oxides. Examples of nitrides include silicon nitride (Si3N4) and aluminum nitride (AlN). Examples of carbides include silicon carbide (SiC) and diamond. Examples of oxides include aluminum oxide (Al2O3).

[0074] There are no particular limitations on the shape or size of the ceramic component 20. However, when the metal / ceramic joint 100 is used as a constituent material of the insulating circuit board, the ceramic component 20 can be a flat plate, for example, with a thickness of more than 0.2 mm and less than 4.0 mm.

[0075] (Bonding layer)

[0076] A bonding layer 30 is formed between the metal component 10 and the ceramic component 20, along the bonding surfaces 10s and 20s. The bonding layer 30 is formed of the aforementioned brazing material and contains Cu, Mg, Mg evaporation inhibiting elements, and active metal elements.

[0077] like Figure 1As shown, the bonding layer 30 has a stacked structure comprising a first layer 31 forming an interface with the metal member 10 and a second layer 32 forming an interface with the ceramic member 20 and in contact with the first layer 31. The thickness of the first layer 31 is, for example, 1 μm or more and 2000 μm or less, and the thickness of the second layer 32 is, for example, 2 nm or more and 5000 nm or less.

[0078] The first layer 31 has a solid solution phase in which at least one of Mg and Mg evaporation suppressing elements is dissolved in Cu, and a compound phase comprising intermetallic compounds containing copper, magnesium, and Mg evaporation suppressing elements. The composition of the solid solution of Mg and Mg evaporation suppressing elements can vary depending on the type of Mg evaporation suppressing element. The compound phase comprises a ternary intermetallic compound composed of Cu, Mg, and Mg evaporation suppressing elements.

[0079] (First layer)

[0080] Here, we will refer to Figure 2 Detailed description of the first layer 31. Figure 2 yes Figure 1 A magnified view of the area A within the dashed line.

[0081] like Figure 2 As shown, the first layer 31 consists of a solid solution phase 31A and a compound phase 31B dispersed therein.

[0082] The solid solution phase 31A is mainly composed of a solid solution of at least one of Cu, Mg, and Mg evaporation suppressing elements. When the Mg evaporation suppressing element is Sn, both Mg and Sn can be dissolved in the solid solution phase 31A. When the Mg evaporation suppressing element is Sb, at least Sb can be dissolved in the solid solution phase 31A, while in some cases, Mg may not be dissolved. When the Mg evaporation suppressing element is Bi, at least Mg can be dissolved in the solid solution phase 31A, while in some cases, Bi may not be dissolved. Furthermore, the solid solution phase 31A may contain active metal elements contained in the brazing material and Si and Al contained in the ceramic component 20 as solid solutions. In the solid solution phase 31A, each element is dissolved as a solid solution, and therefore, the strength of the solid solution phase 31A can be improved due to solid solution strengthening.

[0083] Compound phase 31B comprises a ternary intermetallic compound containing Cu, Mg, and Mg evaporation suppressing elements. Compound phase 31B is formed, for example, by the precipitation of intermetallic compounds, and the intermetallic compounds contained therein depend on the type of Mg evaporation suppressing element. Specifically, when the Mg evaporation suppressing element is Sn, the ternary intermetallic compound is Cu4MgSn. When the Mg evaporation suppressing element is Sb, the ternary intermetallic compound is CuMgSb, and when the Mg evaporation suppressing element is Bi, the ternary intermetallic compound is CuMgBi. When there are two or more Mg evaporation suppressing elements, the ternary intermetallic compound is CuMg(Sn, Sb, Bi), wherein Sn, Sb, and Bi are partially replaced by another. Although compound phase 31B contains at least a ternary intermetallic compound, it may also contain Cu, Mg, and Mg evaporation suppressing elements as other forms of intermetallic compounds. Examples include: binary intermetallic compounds composed of two of Cu, Mg, and Mg evaporation suppressing elements; elemental metallic forms of each element; or intermetallic compounds further containing active metal elements.

[0084] In the first layer 31, preferably, the solid solution phase 31A, which has excellent spreadability and ductility, constitutes the continuous phase. More preferably, as... Figure 2 As shown, the first layer 31 has a phase-separated structure in which the compound phase 31B is arranged in an island pattern within the solid solution phase 31A. The compound phase 31B, containing intermetallic compounds, is more brittle than the solid solution phase 31A, which contains a solid solution, and therefore may contribute to a decrease in the bond strength of the bonding layer 30. When these compound phases 31B are continuously layered throughout the bonding layer 30 and formed at locations corresponding to stress concentration points, crack propagation cannot be prevented when stress is applied to the compound phases 31B, which may lead to a significant reduction in bond strength. At this point, when the bonding layer 30 has such a... Figure 2 When using the island structure shown, a high level of bonding strength can be maintained.

[0085] In the first layer 31, it is preferable that the compound phase 31B is substantially uniformly dispersed across the entire thickness and width of the first layer 31, and that there is no layered continuous phase at stress concentration points. Specifically, when measuring the area ratio of the compound phase 31B in any arbitrary region of the first layer 31 by extracting a unit with a thickness of 10 μm, it is preferable that all area ratios are 40% or less. Because the compound phase 31B exists in any arbitrary region at this predetermined area ratio, the compound phase 31B can be dispersed within the solid solution phase 31A, thereby suppressing the localized occurrence of the compound phase 31B and the resulting reduction in bonding strength. The area ratio of the compound phase 31B is calculated by dividing the total area of ​​the compound phase 31B dispersed in the extraction region by the area of ​​the extraction region.

[0086] Furthermore, in the first layer 31, the solid solution phase 31A preferably constitutes a continuous phase connecting the second layer 32 and the metal component 10. That is, the first layer 31 preferably has a path composed of the solid solution phase 31A that connects the second layer 32 and the metal component 10. The solid solution phase 31A is mainly formed of a solid solution containing Cu, and has excellent malleability and ductility. Since the solid solution phase 31A is not interrupted by the compound phase 31B and constitutes a continuous connection between the second layer 32 and the metal component 10, the metal component 10 and the ceramic component 20 can be firmly bonded together, thereby improving the bonding strength. It is preferable that the continuous phase is formed in a manner where the compound phase 31B is finely dispersed.

[0087] Furthermore, since the bonding layer 30 is formed using the aforementioned brazing material, the generation of voids can be suppressed. When a brazing material containing Mg is used to bond the metal component 10 and the ceramic component 20, there is a concern that the evaporation of Mg contained in the brazing material may cause voids or pinholes (hereinafter collectively referred to as voids) in the first layer 31. The presence of such voids is a factor that reduces the bonding strength between the metal component 10 and the ceramic component 20. In this regard, according to this embodiment, by including a Mg evaporation-inhibiting element in the brazing material, the evaporation of Mg can be suppressed, and the generation of voids in the bonding layer 30 can be reduced.

[0088] Specifically, in the bonding layer 30, when the first layer 31 is observed in cross-sections perpendicular to the bonding surfaces 10s and 20s, it is preferable that the first layer 31 is approximately 10,000 μm thick. 2 No single void with a circular equivalent diameter of 8 μm or greater was observed within any field of view. More preferably, no single void with a circular equivalent diameter of 4 μm or greater was observed, and even more preferably, no single void with a circular equivalent diameter of 1 μm or greater was observed. In other words, the number of voids with a circular equivalent diameter of 8 μm or greater is preferably per 10,000 μm. 2 Less than one. More preferably, the number of pores larger than 4 μm is less than one, and even more preferably, the number of pores larger than 1 μm is less than one.

[0089] In the solid solution phase 31A, at least one of Mg and Mg evaporation suppressing elements is dissolved in Cu crystals, and the amount of each element dissolved in the solid solution is not particularly limited. For example, the amount of Mg dissolved in the solid solution is preferably 5 at.% or less, and among the Mg evaporation suppressing elements, the amount of Sn dissolved in the solid solution is preferably 5 at.% or less. Furthermore, for example, the amount of Sb dissolved in the solid solution is preferably 4 at.% or less, and the amount of Bi dissolved in the solid solution is preferably 1 at.% or less. The amount of solid solution can be measured by, for example, energy-dispersive X-ray spectroscopy (EDX) analysis of the solid solution phase 31A.

[0090] When the Mg evaporation inhibiting element in the solid solution phase 31A is Sn, it is more preferable that the ratio A / B is 0.5 or more and 2.0 or less, where A is the amount of Mg dissolved in the solid solution phase 31A and B is the amount of Mg evaporation inhibiting element dissolved in the solid solution phase 31A. By forming a solid solution of Mg and Sn in this ratio, the bonding strength of the bonding layer 30 can be further improved.

[0091] At the interface of the first layer 31 on the side of the metal component 10, metal can diffuse from the metal component 10 to the first layer 31, forming an interface reaction layer containing elements from the metal component 10 and elements from the bonding layer 30 in some cases.

[0092] (Second layer)

[0093] In the bonding layer 30, the second layer 32 constituting the interface with the ceramic component 20 comprises a compound of an active metal element. The compound of the active metal element may also contain elements derived from the ceramic component 20. For example, when the active metal element is Ti and the ceramic component 20 contains nitrides such as silicon nitride, the second layer 32 is primarily composed of titanium nitride (TiN), which is a compound containing an active metal element. Furthermore, for example, when the active metal element is Ti and the ceramic component 20 contains carbides such as silicon carbide, the second layer 32 is primarily composed of titanium carbide (TiC), which is a compound containing an active metal element. The compound of the active metal element constituting the second layer 32 may sometimes also contain Mg, an evaporation suppressant element.

[0094] In this embodiment, the second layer 32 may further comprise silicides or aluminides of active metal elements. When the ceramic component 20 is made of Si3N4, the second layer 32 may comprise silicides of active metal elements such as Ti5Si3, and when the ceramic component 20 is made of AlN, the second layer 32 may comprise aluminides of active metal elements such as TiAl.

[0095] (Joint strength)

[0096] In this embodiment, by forming the bonding layer 30 with the aforementioned brazing material, high bonding strength between the metal component 10 and the ceramic component 20 can be achieved. Specifically, in this embodiment, the shear strength of the bonding layer 30 is 20 MPa or more. Furthermore, a shear strength of 50 MPa or more can be obtained, and even further, a shear strength of 80 MPa or more can be obtained.

[0097] In this embodiment, the tensile strength of the bonding layer 30 is 40 MPa or more. Furthermore, a tensile strength of 90 MPa or more can be obtained, and even further, a tensile strength of 140 MPa or more can be obtained.

[0098] like Figure 3As shown in (a), the shear strength of the bonding layer 30 here refers to the magnitude of the shear load per unit area required to cause the bonding layer 30 to fail (shear failure) when stress (shear stress) is applied to the bonding layer 30 to cause the metal member 10 and the ceramic member 20 to move in opposite directions parallel to the bonding surfaces 10s and 20s. Additionally, as... Figure 3 As shown in (b), the tensile strength of the bonding layer 30 refers to the magnitude of the tensile load per unit area required to break the bonding layer 30 when stress (tensile stress) is applied to the bonding layer 30 to pull the metal member 10 and the ceramic member 20 apart in directions perpendicular to the bonding surfaces 10s and 20s.

[0099] (3) Manufacturing method of metal / ceramic joint

[0100] Next, refer to Figure 4 (a) to Figure 4 (c) describes the manufacturing method of the metal / ceramic joint 100 described above.

[0101] First, such as Figure 4 As shown in (a), the metal component 10 and the ceramic component 20 are arranged in a stacked manner, with the brazing material 50 between them.

[0102] The brazing material 50 can be any of the brazing materials described above. For example, a brazing material containing 50 at.% to 80 at.% Cu, 1 at.% to 15 at.% Mg, 1 at.% to 20 at.% Mg evaporation inhibiting element, and 0.1 at.% to 10 at.% active metal element can be used. In the brazing material 50, Cu, Mg, Mg evaporation inhibiting element, and active metal element can be contained as a powder in the form of the aforementioned compounds. In this case, it is preferable that at least a portion of Mg is added in the form of an alloy powder formed from an intermetallic compound containing at least Mg and Mg evaporation inhibiting element. For example, a powder containing Cu, an alloy powder formed from an intermetallic compound containing at least Mg and Mg evaporation inhibiting element, and a powder containing active metal element can be appropriately mixed in such a way that each element has a predetermined content.

[0103] As a method for distributing the brazing material 50 onto the predetermined bonding surfaces 10s' and 20s' of the metal component 10 and the ceramic component 20, known methods such as screen printing, transfer printing, dispensing, inkjet printing, spraying, sputtering, and vapor deposition can be used, with screen printing being more preferred. In the case of a powder-based preparation method such as screen printing or dispensing, the aforementioned paste-like powder is preferred. The brazing material 50 can be formed into a pre-shaped form by shaping the powdered brazing material. Furthermore, before lamination, the brazing material 50 can be integrally bonded to the metal component 10 or the ceramic component 20, and methods such as plating by rolling or metallization by heat treatment can be used as the integration method.

[0104] Next, as Figure 4 As shown in (b), a laminate 100' of metal component 10 and ceramic component 20, in which brazing material 50 is intermediate, is heated and held in a predetermined atmosphere while being pressurized in the lamination direction. The predetermined atmosphere can be any of a vacuum atmosphere (reduced pressure atmosphere), an inactive gas atmosphere, and a reducing atmosphere.

[0105] The heating temperature during bonding can be, for example, equal to or higher than the melting point of the brazing material 50, and equal to or lower than the melting point of the metal component 10. Furthermore, it is preferable that the heating temperature is 115% or less of the melting point (°C) of the brazing material 50, more preferably 101% or more and 110% or less. This improves the diffusion of the active metal elements, making it easier to form the second layer 32. For example, when using the brazing material 50 of this embodiment, the heating temperature is preferably 720°C or more and 1000°C or less, more preferably 850°C or less. As the heat treatment furnace for bonding, known furnaces such as static batch furnaces, multi-chamber furnaces, belt conveyor furnaces, or roller kilns can be used.

[0106] Other conditions for engagement include the following:

[0107] Oxygen concentration: 0.01 vol.ppm or more and 1000 vol.ppm or less, or more preferably 0.1 vol.ppm or more and 100 vol.ppm or less.

[0108] Pressure: Above 0.5 kPa.

[0109] Duration: There are no special restrictions, but for example, more than 3 minutes and less than 120 minutes.

[0110] During heating, a liquid phase needs to be formed in a portion of the brazing material 50, and furthermore, an active metal element needs to melt in this liquid phase. This can be achieved, for example, in the case of a Cu-Mg-Sb alloy where the active metal is Ti and the Mg evaporation inhibitor is Sb, by setting the heating temperature to 720°C or higher. However, in some cases, excessively high heating temperatures may cause Mg evaporation to exceed the effect of the Mg evaporation inhibitor, making it difficult to form a liquid phase or, in some cases, creating voids in the resulting bond layer 30. These problems can be avoided by setting the heating temperature below 1000°C. By applying a pressure of 0.5 kPa or higher, a tight contact between the metal component 10 and the ceramic component 20 between the brazing material 50 can be maintained, thereby improving the bond strength between the metal component 10 and the ceramic component 20. There is no particular upper limit to the pressure, but it can be, for example, about 20 kPa.

[0111] The heated laminate 100' is then cooled. As a result, a product is manufactured. Figure 4 The metal / ceramic joint 100 shown in (c).

[0112] (4) Effect

[0113] According to this implementation plan, one or more of the following effects can be obtained.

[0114] (a) According to the brazing material of this embodiment, since the brazing material contains Cu, Mg, at least one Mg evaporation-inhibiting element selected from Sn, Sb, and Bi, and an active metal element, at least Cu, Mg, and the Mg evaporation-inhibiting element can combine to form an intermetallic compound during heating and bonding. This intermetallic compound is characterized by its easy melting at the bonding temperature due to its eutectic reaction with Cu, and its combination with the Mg evaporation-inhibiting element makes it difficult for Mg to evaporate from the eutectic melt during melting. That is, during the time period from when the components contained in the brazing material melt to when it solidifies, Mg evaporation can be suppressed because Mg combines with the Mg evaporation-inhibiting element, etc. As a result, in the bonding layer 30 obtained by heating the brazing material, void formation caused by Mg evaporation can be reduced, a dense phase structure can be obtained, and high bonding strength can be achieved.

[0115] (b) Furthermore, since the brazing material contains Mg, the melting point of Cu can be lowered, and thus high bonding strength can be achieved at low heating temperatures, for example, in the range of above 720°C and below 1000°C. In addition, the presence of Mg improves the wettability to both the metal component 10 and the ceramic component 20.

[0116] (c) The brazing material contains 1 at.% to 15 at.% of Mg, 1 at.% to 20 at.% of a Mg evaporation inhibitor, and 0.1 at.% to 10 at.% of an active metal element, satisfying X - 6 ≤ Y ≤ X + 6, where X (at.%) is the Mg content and Y (at.%) is the Mg evaporation inhibitor content. By including the elements within this content range, the effects described in (a) can be obtained more stably.

[0117] (d) Preferably, the brazing material forms a paste and comprises Cu powder containing Cu and an alloy powder formed from an intermetallic compound containing at least Mg and a Mg evaporation-inhibiting element. Since Mg and the Mg evaporation-inhibiting element are pre-formed into an intermetallic compound, Mg evaporation can be more reliably suppressed when the brazing material is heated, resulting in a more reliable increase in bond strength.

[0118] (e) The brazing material preferably contains alloy powder such that the content of Mg derived from the alloy powder accounts for more than 40% of the total Mg content in the brazing material. This makes it possible to obtain the above-mentioned effects (d) more reliably.

[0119] (f) When the brazing material of this embodiment is used to join the metal component 10 and the ceramic component 20, the bonding layer 30 is formed as a laminated structure comprising a first layer 31 forming an interface with the metal component 10 and a second layer 32 forming an interface with the ceramic component 20. Since the first layer 31 has a solid solution phase in which at least one of Mg and Mg evaporation-inhibiting elements is dissolved in Cu, and a compound phase comprising Cu, Mg, and an intermetallic compound containing Mg evaporation-inhibiting elements, voids in the first layer 31 can be suppressed. Furthermore, since the compound phase 31B further contains Mg evaporation-inhibiting elements, higher strength can be achieved compared to the case where Mg evaporation-inhibiting elements are not present. Since the second layer 32 contains a compound of an active metal element, it helps to improve the bonding between the metal component 10 and the bonding layer 30. The bonding layer 30 having this phase structure can firmly bond the metal component 10 and the ceramic component 20 together, thereby achieving high bonding strength.

[0120] (g) By suppressing the generation of voids in the first layer 31 of the bonding layer 30, preferably, when the first layer 31 is viewed in a cross section perpendicular to the bonding surface, the voids are within 10,000 μm. 2 No single void with a circular equivalent diameter greater than 8 μm was observed in any field of view.

[0121] (h) Preferably, the first layer 31 of the bonding layer 30 has a phase structure in which the solid solution phase 31A constitutes a continuous phase as a parent phase and as an island phase, and the compound phase 31B is dispersed as an island phase. When the compound phase 31B is locally concentrated, the corresponding region becomes prone to failure when stress is applied. However, by dispersing the compound phase 31B, failure due to the applied load can be suppressed, and the bonding strength can be improved more reliably.

[0122] (i) In the first layer 31 of the bonding layer 30, when an arbitrary region with a thickness of 10 μm is extracted and the area ratio of the compound phase 31B in that arbitrary region is measured, it is preferable that all area ratios are 20% or more and 40% or less. When the area ratio of the compound phase 31B falls within a predetermined range, the compound phase 31B is finely dispersed in the solid solution phase 31A, and the effect described in (h) can be obtained more reliably.

[0123] (j) In the first layer 31 of the bonding layer 30, the solid solution phase 31A is preferably configured as a continuous phase connecting the second layer 32 and the metal member 10. This allows the first layer 31 to have a path formed by the solid solution phase 31A, thereby more reliably improving the bonding strength.

[0124] (k) Since the bonding layer 30 has the phase structure described in any one of (f)-(j) above, the shear strength of the bonding layer 30 can be increased to 20 MPa or more. Furthermore, the tensile strength of the bonding layer 30 can be increased to 40 MPa or more.

[0125] (l) Since the bonding layer 30 is formed using a brazing material with Cu as the main phase, migration caused by Ag as the main phase can be suppressed. That is, high migration resistance can be achieved in the bonding layer 30.

[0126] <Other Implementations of this Disclosure>

[0127] Although the embodiments of this disclosure have been specifically described above, this disclosure is not limited to the above embodiments and can be modified in various ways without departing from the spirit and scope of this disclosure.

[0128] The above embodiments illustrate a case where the metal component 10 and the ceramic component 20 are joined together, but this disclosure is not limited to this, and two metal components 10 can also be joined together. In this case, the two metal components 10 can be made of the same metal or dissimilar metals.

[0129] The metal / ceramic bond 100 of this embodiment can be used, for example, as an insulating circuit board. In this case, for example, in order to form a circuit pattern in the metal component 10, etching can be performed after a photoresist is applied to the metal component 10. There are no particular limitations on the type of photoresist, and known photoresists such as thermosetting and UV-curing photoresists can be used. There are no particular limitations on the method used to apply the photoresist, and methods such as applying a film-like photoresist film, screen printing, and inkjet coating can be used. Furthermore, after removing unwanted portions of the metal component 10 from the metal / ceramic bond 100 by etching, unwanted portions of the bonding layer 30 can be further removed as needed. Moreover, the metal / ceramic bond 100 is not limited to the use of an insulating circuit board, but can be widely used in various applications, such as radiators and components of internal combustion engines and generators. In these cases, the same effects as in the embodiments described above can also be obtained.

[0130] Example

[0131] In this embodiment, the prepared brazing material is used to join metal components and ceramic components, or to join two metal components together, and the joint strength of the resulting joint is evaluated. Specifically, the following applies:

[0132] (1) Preparation

[0133] For the metal components, 2.0 mm thick copper material, 6.0 mm thick iron alloy material (42ALLOY), and 6.0 mm thick steel material (SUS304) are prepared. For the ceramic components, 0.3 mm thick silicon nitride (Si3N4) sheets, 0.3 mm thick silicon carbide (SiC) sheets, 0.3 mm thick AlN sheets, 0.3 mm thick Al2O3 sheets, and 0.3 mm thick diamond sheets are prepared.

[0134] Furthermore, as powders for preparing brazing materials, powders containing Cu, Mg, Mg evaporation inhibiting elements, and active metal elements are prepared. Specifically, as powders containing Cu, pure Cu powder is prepared. As powders containing Mg or Mg evaporation inhibiting elements, five alloy powders are prepared: an alloy powder composed of Cu4MgSn and Cu, an alloy powder composed of CuMgSb and Cu, an alloy powder composed of CuMgBi and Cu, an alloy powder composed of Cu2Mg and Cu, and an alloy powder composed of Cu3Sn and Cu. As powders containing Mg, elemental Mg metal powder is prepared. As powders containing active metal elements: TiH2 powder, an alloy powder composed of CuCaSn and Cu, an alloy powder composed of CuMgY, Cu2Mg, and Cu, and an alloy powder composed of Cu6Ce, Cu2Mg, and Cu are prepared. The average particle size (D50) of each powder is set to 45 μm or less. The alloy powders are produced by atomization.

[0135] (2) Preparation of brazing materials

[0136] First, the powders were mixed such that the contents of Cu, Mg, Mg evaporation inhibitors, and active metal elements were as shown in Tables 1 to 6. The mixture was then converted into a paste to prepare brazing materials for samples 1 to 42 and 45 to 232. Samples 214 to 232 contained any one of the active metal elements Cr, Mo, V, Nb, and Zr, which will be described later. In the conversion to paste, polyethylene glycol and diethylene glycol monobutyl ether with a molecular weight of less than 400 were used as solvents, and the solvent ratio in the paste was set to 9% by mass. The brazing material for sample 43 was prepared in the same manner as samples 1 to 42, except that Cu and Mg evaporation inhibitors were not added. The brazing material for sample 44 was prepared in the same manner as samples 1 to 42, except that only elemental Mg powder was used. In Tables 1 to 5, content X represents the Mg content [at.%], and content Y represents the total Mg evaporation inhibitor content [at.%].

[0137] [Table 1]

[0138]

[0139] [Table 2]

[0140]

[0141] [Table 3]

[0142]

[0143] [Table 4]

[0144]

[0145] [Table 5]

[0146]

[0147] [Table 6]

[0148]

[0149] (3) Preparation of the joint

[0150] Next, in samples 1 to 213, the prepared paste-like brazing material was applied to the predetermined bonding surfaces of the first components shown in Tables 1 to 6 by screen printing. Then, a second component was directly disposed on the applied paste layer, and a pressure of 8 kPa was applied in the lamination direction. Then, at a pressure of 1.0 × 10⁻⁶ kPa... -2 The joints of samples 1 to 213 were produced by heat treatment at 800°C (820°C for samples 43 and 44 only) for 60 minutes in a vacuum atmosphere below Pa. In samples 214 to 232, a predetermined molar amount of active metal elements selected from Cr, Mo, V, Nb, and Zr was sputtered onto the predetermined bonding surface of the first component shown in Table 6, and then a prepared paste-like brazing material was applied thereon by screen printing. The element ratio column of the brazing material in Table 6 shows the ratio including the sputtered active metal elements. Next, a second component was directly disposed on the applied paste layer, and a pressure of 8 kPa was applied along the lamination direction. Then, at 1.0 × 10⁻⁶ kPa… -2 The conjugates of samples 214 to 232 are produced by heat treatment at 800°C for 60 minutes in a vacuum atmosphere below Pa.

[0151] (4) Evaluation

[0152] The phase structure and bonding strength of the bonding layer of the produced bonded body are evaluated using the following methods.

[0153] The phase structure of the bonding layer was evaluated by observing the cross-section of the bonding layer. Specifically, the first layer was observed in a cross-section perpendicular to the bonding surface to confirm (1) that the solid solution phase and the compound phase have an island structure; (2) that there is a path (continuous phase) in the first layer consisting of the solid solution phase that connects the second layer and the copper material; and (3) that the phase structure is within approximately 10,000 μm. 2 Within a given field of view, no single void with a circular equivalent diameter greater than 8 μm was observed in the first layer.

[0154] The elements dissolved in the first layer of the solid solution were quantitatively determined. Specifically, energy-dispersive X-ray spectroscopy (EDX) was used to measure the content of elements dissolved in the solid solution.

[0155] The joint strength of the joint was evaluated by shear strength testing. Specifically, for the joint, copper material was machined into a cylindrical shape with a diameter of 3 mm and a height of 2 mm, exposing the joint surface of the surrounding ceramic material to prepare a test piece. Then, as... Figure 5 As shown, a ceramic material is fixed in place, and a cylindrical copper material is pressed against it in a direction parallel to the joint surface using a displacement clamp. The stress at which the joint layer fails (shear failure) is measured, and the shear strength of the joint layer is calculated based on this value. The shear test position (the contact height H of the displacement clamp) is set at a height of 200 μm above the exposed surface of the ceramic material, and the moving speed of the displacement axis is set to 100 μm / s.

[0156] Furthermore, the tensile strength of the bond layer was calculated based on the results of shear strength tests. The tensile strength of the bond layer can be calculated from the shear strength using the von Mises equation, and its magnitude is approximately 1.73 times the shear strength.

[0157] The results are shown in Tables 1 to 6.

[0158] (5) Evaluation results (samples 1 to 7)

[0159] When the cross-section of the bonding layer of sample 1 was observed, it was confirmed that the bonding layer had the following characteristics: Figure 6 The phase structure shown. Figure 6 This is a magnified image of a portion of the cross-section of the bonding layer of sample 1. For example... Figure 6 As shown, it is confirmed that a second layer 32 containing a compound of an active metal element is formed at the interface of the bonding layer 30 on the ceramic component 20 side. It is also confirmed that a first layer 31 is formed on the second layer 32, and that the first layer 31 has an island structure in which the compound phase 31B is dispersed as an island phase within a solid solution phase 31A, which is a marine phase serving as the parent phase. Furthermore, it is confirmed that the first layer 31 has a pathway (continuous phase) composed of the solid solution phase 31A connecting the second layer 32 and the copper material. It is also confirmed that the first layer 31 has no voids with a circular equivalent diameter greater than 1 μm.

[0160] Furthermore, EDX measurements confirmed that compound phase 31B is formed from an intermetallic compound of Cu, Mg, and Sn, specifically Cu4MgSn. On the other hand, it was confirmed that solid solution phase 31A is formed by Mg and Sn dissolved in the Cu phase. The amount of Mg dissolved in the solid solution is 1.0 at.%, and the amount of Sn dissolved in the solid solution is 1.6 at.%.

[0161] Furthermore, as shown in Table 1, the shear strength of Sample 1 was confirmed to be 186.4 MPa, and when converted based on this value, the tensile strength was 322.9 MPa. That is, it is confirmed that high bond strength can be achieved.

[0162] In samples 2 to 7, as shown in Table 1, the contents of Mg and Sn in the brazing materials varied compared to sample 1, but it was confirmed that the same phase structure as sample 1 could be achieved. Furthermore, it was confirmed that in all samples, as with sample 1, a solid solution phase 31A was formed by Mg and Sn dissolving in the Cu phase, and a compound phase 31B was formed by containing Cu4MgSn. The amount of Mg dissolved in the solid solution was 5.0 at.% or less, and the amount of Sn dissolved in the solid solution was 5.0 at.% or less. Furthermore, it was confirmed that in all samples, the shear strength was 20 MPa or more, and the tensile strength, when converted based on this value, was 40 MPa or more.

[0163] (Samples 8 to 14)

[0164] When observing the cross-section of the bonding layer of sample 8, it was confirmed that... Figure 7 The phase structure shown. Figure 7 This is a magnified image of a portion of the cross-section of the bonding layer of sample 8. (Example:) Figure 7 As shown, it is confirmed that the bonding layer 30 of sample 8 has the same phase structure as the bonding layer 30 of sample 1. In particular, it is confirmed that the first layer 31 has an island structure in which the compound phase 31B is dispersed as an island phase in the solid solution phase 31A, which is the parent phase. Furthermore, it is confirmed that there is a path (continuous phase) in the first layer 31 formed by the solid solution phase 31A that connects the second layer 32 and the copper material. It is also confirmed that there are no voids with a circular equivalent diameter greater than 1 μm in the first layer 31.

[0165] Furthermore, EDX measurements confirmed that compound phase 31B is formed from an intermetallic compound of Cu, Mg, and Sb, specifically CuMgSb. On the other hand, it was confirmed that Sb is dissolved in the solid solution phase 31A, but Mg is not dissolved in the Cu phase. The amount of Sb dissolved is 3.1 at.%.

[0166] Furthermore, as shown in Table 1, the shear strength of sample 8 was confirmed to be 139.5 MPa, and when converted based on this value, the tensile strength was 241.6 MPa. That is, it is confirmed that high bond strength can be achieved.

[0167] In samples 9 to 14, as shown in Table 1, although the contents of Mg and Sb in the brazing materials varied compared to sample 8, it was confirmed that the same phase structure as sample 8 could be obtained. In all samples, similar to sample 8, it was confirmed that the solid solution phase 31A was formed by Sb dissolved in the Cu phase while Mg remained undissolved, and the compound phase 31B was formed by containing CuMgSb. The amount of Sb dissolved in the solid solution was less than 4.0 at.%. Furthermore, it was confirmed that in all samples, the shear strength was greater than 20 MPa, and when converted based on this value, the tensile strength was greater than 40 MPa.

[0168] (Samples 15 to 18)

[0169] When the cross-section of the bonding layer 30 of sample 15 was observed, it was confirmed that the bonding layer 30 has the following characteristics: Figure 8 The phase structure shown. Figure 8 This is a magnified image of a portion of the cross-section of the bonding layer 30 of sample 15. (Example) Figure 8 As shown, it is confirmed that the bonding layer 30 of sample 15 has the same phase structure as the bonding layer 30 of sample 1. In particular, it is confirmed that the first layer 31 has an island structure in which the compound phase 31B is dispersed as an island phase in the solid solution phase 31A, which is the parent phase. Furthermore, it is confirmed that there is a path (continuous phase) in the first layer 31 consisting of the solid solution phase 31A that connects the second layer 32 and the copper material. It is also confirmed that there are no voids with a circular equivalent diameter greater than 1 μm in the first layer 31.

[0170] Furthermore, EDX measurements confirmed that compound phase 31B is formed from an intermetallic compound of Cu, Mg, and Sb, specifically CuMgBi. On the other hand, it was confirmed that in the solid solution phase 31A, Mg is dissolved in the Cu phase, while Bi remains undissolved. The amount of Mg dissolved is 0.4 at.%.

[0171] Furthermore, as shown in Table 1, the shear strength of sample 15 was confirmed to be 24.8 MPa, and when converted based on this value, the tensile strength was 43 MPa. That is, it is confirmed that high bond strength can be achieved.

[0172] In samples 16 to 18, as shown in Table 1, the contents of Mg and Bi in the brazing materials varied compared to sample 15, but it was confirmed that the same phase structure as sample 15 could be obtained. In all samples, as with sample 15, it was confirmed that the solid solution phase 31A was formed by Mg dissolved in the Cu phase while Bi remained undissolved, and the compound phase 31B was formed by containing CuMgBi. In all samples, the amount of Mg dissolved was less than 5.0 at.%. Furthermore, in all samples, the shear strength was confirmed to be ≥20 MPa, and when converted based on this value, the tensile strength was ≥40 MPa.

[0173] (Samples 19 to 25)

[0174] In samples 19 to 25, the contents of Mg, Sn, and Sb varied compared to those in samples 1 and 8, but it was confirmed that the same phase structure as that in samples 1 and 8 could still be obtained. In all samples, an island structure of solid solution phase 31A and compound phase 31B was confirmed to form, with a path consisting of solid solution phase 31A in the first layer 31 connecting the second layer 32 and the copper material, and no voids with a circular equivalent diameter greater than 1 μm.

[0175] (Samples 26 to 33)

[0176] In samples 26 to 33, brazing materials were prepared by incorporating two Mg evaporation-inhibiting elements, Sn and Sb. The same phase structure as in sample 1 was obtained in the bonding layer 30 of samples 26 to 33. A sea-island structure of solid solution phase 31A and compound phase 31B was also confirmed, forming a path in the first layer 31 consisting of solid solution phase 31A that connects the second layer 32 and the copper material, and without any voids with a circular equivalent diameter greater than 1 μm.

[0177] Furthermore, EDX measurements confirmed that compound phase 31B is formed from an intermetallic compound of Cu, Mg, Sn, and Sb. This intermetallic compound consists of Cu, Mg, Sn, and partially substituted Sb. On the other hand, it was confirmed that solid solution phase 31A is composed of Mg, Sn, and Sb dissolved in the Cu phase.

[0178] Furthermore, as shown in Table 1, it was confirmed that the shear strength was above 20 MPa in all samples, and the tensile strength was above 40 MPa when converted based on this value.

[0179] (Samples 34 to 39)

[0180] In samples 34 to 39, as shown in Table 1, the brazing materials were prepared in the same manner as in sample 1 to produce the joints, except that the type of ceramic component was changed from Si3N4 to SUS304, AlN, Al2O3, SiC or diamond.

[0181] In the bonding layer 30 of samples 34 to 39, the same phase structure as that of sample 1 was obtained. It was also confirmed that an island structure of solid solution phase 31A and compound phase 31B was formed, and a path composed of solid solution phase 31A was formed in the first layer 31 to connect the second layer 32 and the copper material, and there were no voids with a circular equivalent diameter greater than 1 μm.

[0182] Furthermore, as shown in Table 1, it was confirmed that the shear strength was above 20 MPa in all samples, and the tensile strength was above 40 MPa when converted based on this value.

[0183] (Samples 40 to 42)

[0184] In samples 40 to 42, as shown in Table 1, an iron alloy (42ALLOY) was used as the metal component, and a Si3Ni4 substrate was used as the ceramic component. It was confirmed that in all samples, the same phase structure as in sample 1 was obtained, and the predetermined bond strength could be achieved.

[0185] (Samples 43 and 44)

[0186] As shown in Table 1, in sample 43, which uses brazing material containing both Mg and Ti, and in sample 44, which uses brazing material containing only Mg, the shear strength is less than 20 MPa and the tensile strength is less than 40 MPa, and it is confirmed that no practical bond strength was obtained (the bond was not substantially achieved). In these samples, a bond strength sufficient to withstand the processing required for observation of the cross-sectional microstructure cannot be obtained, and therefore the bond layer in the cross-section perpendicular to the bond surface cannot be observed.

[0187] (Samples 45 to 232)

[0188] As shown in Tables 2 to 6, it was confirmed that the shear strength was above 20 MPa in all samples 45 to 232, and the tensile strength was above 40 MPa when converted based on this value.

[0189] <Preferred aspects of this disclosure>

[0190] The preferred aspects of this disclosure are noted below. These aspects can be combined with each other.

[0191] (Postscript 1)

[0192] A brazing material is provided, comprising:

[0193] Cu;

[0194] Mg;

[0195] Choose at least one first element from the group consisting of Sn, Sb, and Bi; and

[0196] It is selected from at least one second element in the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, Ca, Ce, La, Sm, Yb, Nd, Gd and Er.

[0197] (Postscript 2)

[0198] Preferably, the brazing material according to Appendix 1 is provided.

[0199] The content of Mg is above 1 at.% and below 15 at.%, the content of the first element is above 1 at.% and below 20 at.%, the content of the second element is above 0.1 at.% and below 10 at.%, and when the content of Mg is X at.% and the content of the first element is Y at.%, the relationship X-6≤Y≤X+6 is satisfied.

[0200] (Note 3)

[0201] Preferably, a brazing material according to Appendix 1 or 2 is provided, which is formed in the form of a paste, comprising Cu powder containing Cu and alloy powder having an intermetallic compound containing at least Mg, a first element and a second element.

[0202] (Postscript 4)

[0203] Preferably, a joint is provided, comprising:

[0204] The first component is made of metal;

[0205] A second component that joins with the first component and is made of the same or different metal or ceramic as the first component; and

[0206] The bonding layer on the joint surface of the first component and the second component,

[0207] The bonding layer includes:

[0208] Cu;

[0209] Mg;

[0210] Choose at least one first element from the group consisting of Sn, Sb and Bi;

[0211] as well as

[0212] It is selected from at least one second element in the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, Ca, Ce, La, Sm, Yb, Nd, Gd and Er.

[0213] (Note 5)

[0214] Provide the joint as described in Appendix 4,

[0215] The bonding layer includes:

[0216] A first layer, forming an interface with a first component and comprising a solid solution phase in which at least one of Mg and a first element is dissolved in Cu, and a compound phase comprising an intermetallic compound comprising Cu, Mg, and the first element; and

[0217] The second layer forms an interface with the second component, contains a compound of the second element, and is in contact with the first layer.

[0218] (Note 6)

[0219] Preferably, the joint according to Appendix 5 is provided, wherein when the first layer is viewed in a cross section perpendicular to the joint surface, the number of voids with a circular equivalent diameter of 8 μm or more is 10,000 μm. 2 Less than one.

[0220] (Note 7)

[0221] Preferably, a joint according to Appendix 5 is provided, wherein the first layer has a path consisting of a solid solution phase and connecting the second layer and the first member.

[0222] (Note 8)

[0223] Preferably, a joint is provided according to any one of Appendices 4 to 7, wherein the shear strength of the joint layer is 20 MPa or more.

[0224] (Note 9)

[0225] Preferably, a joint is provided according to any one of Appendices 4 to 8, wherein the tensile strength of the joint layer is 40 MPa or more.

[0226] (Postscript 10)

[0227] A method for manufacturing a brazing material for joining a first component made of metal and a second component made of the same or different metal or ceramic as the first component is provided.

[0228] The powder comprising Cu, Mg, at least one first element selected from the group consisting of Sn, Sb and Bi, and at least one second element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, Ca, Ce, La, Sm, Yb, Nd, Gd and Er is mixed with a solvent to obtain a paste-like brazing material.

[0229] (Postscript 11)

[0230] A method for manufacturing an assembly is provided, the method comprising:

[0231] In the configuration process, a first component made of metal and a second component made of the same or different metal or ceramic as the first component are stacked together in a manner separated by brazing material; and

[0232] The heating process involves applying pressure in the lamination direction while heating and maintaining the laminate of the first and second components.

[0233] The material comprising at least one first element selected from the group consisting of Cu, Mg, Sn, Sb and Bi, and at least one second element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, Ca, Ce, La, Sm, Yb, Nd, Gd and Er is used as a brazing material.

[0234] (Postscript 12)

[0235] Preferably, a method for manufacturing the joint according to Appendix 11 is provided, wherein the brazing material is formed in a paste form, comprising Cu powder containing Cu and alloy powder formed from an intermetallic compound containing at least Mg and a first element.

[0236] (Postscript 13)

[0237] Preferably, a method for manufacturing the laminate according to Appendix 11 or 12 is provided, wherein in the heating step, the laminate is heated to a temperature of 720°C or higher and 1000°C or lower.

[0238] Explanation of reference numerals in the attached figures

[0239] 100 Metal / Ceramic Joint

[0240] 100' laminate

[0241] 10. Metal components (first component)

[0242] 10s mating surface

[0243] 20. Ceramic component (second component)

[0244] 20s mating surface

[0245] 30 Bonding layer

[0246] 31 First Floor

[0247] 31A solid solution phase

[0248] 31B compound phase

[0249] 32 Second layer

[0250] 50 Brazing materials

Claims

1. A brazing material, comprising: Cu; Mg; Choose at least one first element from the group consisting of Sn, Sb and Bi; and It is selected from at least one second element in the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, Ca, Ce, La, Sm, Yb, Nd, Gd and Er.

2. The brazing material according to claim 1, The content of Mg is 1 at.% or more and 15 at.% or less, the content of the first element is 1 at.% or more and 20 at.% or less, the content of the second element is 0.1 at.% or more and 10 at.% or less, and when the content of Mg is X at.% and the content of the first element is Y at.%, X-6≤Y≤X+6 is satisfied.

3. The brazing material according to claim 1 or 2, which is formed in the form of a paste, comprising Cu powder containing Cu and alloy powder having an intermetallic compound containing at least Mg, the first element and the second element.

4. A joint comprising: The first component is made of metal; A second component that engages with the first component and is made of the same or different metal or ceramic as the first component; and The bonding layer on the joint surface of the first component and the second component. The bonding layer comprises: Cu; Mg; Choose at least one first element from the group consisting of Sn, Sb and Bi; as well as It is selected from at least one second element in the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, Ca, Ce, La, Sm, Yb, Nd, Gd and Er.

5. The joint according to claim 4, The bonding layer comprises: A first layer, the first layer forming an interface with the first component and comprising a solid solution phase in which at least one of Mg and the first element is dissolved in Cu, and a compound phase comprising an intermetallic compound comprising Cu, Mg, and the first element; and The second layer forms an interface with the second component, contains a compound of the second element, and is in contact with the first layer.

6. The joint according to claim 5, wherein when the first layer is viewed in a cross-section perpendicular to the joint surface, the number of voids with a circular equivalent diameter of 8 μm or more is 10,000 μm. 2 Less than one.

7. The joint according to claim 5, wherein the first layer has a path formed by the solid solution phase and connecting the second layer and the first member.

8. The joint according to claim 4 or 5, wherein the shear strength of the joint layer is 20 MPa or more.

9. The joint according to claim 4 or 5, wherein the tensile strength of the joint layer is 40 MPa or more.

10. A method for manufacturing a brazing material for joining a first component made of metal and a second component made of the same or different metal or ceramic as the first component. The powder comprising Cu, Mg, at least one first element selected from the group consisting of Sn, Sb and Bi, and at least one second element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, Ca, Ce, La, Sm, Yb, Nd, Gd and Er is mixed with a solvent to obtain a paste-like brazing material.

11. A method for manufacturing an assembly, the method comprising: The configuration process involves stacking a first component made of metal and a second component made of the same or different metal or ceramic as the first component in a manner separated by a brazing material. and The heating process involves applying pressure in the lamination direction while heating and maintaining the laminate of the first and second components. The material comprising at least one first element selected from the group consisting of Cu, Mg, Sn, Sb and Bi, and at least one second element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y, Ca, Ce, La, Sm, Yb, Nd, Gd and Er is used as the brazing material.

12. The method of manufacturing a joint according to claim 11, wherein the brazing material is formed as a paste comprising Cu powder containing Cu and alloy powder formed from an intermetallic compound containing at least Mg and the first element.

13. The method of manufacturing a composite according to claim 11 or 12, wherein in the heating step, the laminate is heated to a temperature of 720°C or higher and 1000°C or lower.

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