A transition layer powder, a transition layer and a preparation method and application thereof

Abstract

The present application relates to a kind of transition layer powder, transition layer and its preparation method and application, the preparation raw material of the transition layer powder is composed of tungsten, manganese oxide, silicon dioxide and aluminium oxide;With mass percentage, the mass percentage of tungsten in the preparation raw material of the transition layer powder is 75wt% or more;The mass ratio of tungsten and manganese oxide is 8:1 to 20:1 The preparation raw material of the transition layer powder provided by the present application uses tungsten, manganese oxide, silicon dioxide and aluminium oxide, and controls the ratio of tungsten and manganese oxide, so that it can form the transition layer with the tungsten skeleton structure of small pore when being applied on high-purity alumina ceramic substrate, it is convenient for copper-based brazing filler metal to melt into the tungsten skeleton pore of transition layer and form tungsten copper infiltration effect, and has the effect of wetting tungsten material, so as to improve the connection strength between high-purity alumina ceramic substrate with purity of 99wt% or more and tungsten material.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of welding, and relates to a welding transition layer, in particular to a transition layer powder, a transition layer and a preparation method and application thereof. BACKGROUND

[0002] The Langmuir probe for the Thomack device is made of pure tungsten, and the internal insulating material is high-purity alumina ceramic with a purity of more than 99wt%. The two materials are greatly different in nature, and are difficult to connect as dissimilar materials during welding. The prior art forms a metalized transition layer on the surface of the ceramic, and then connects the two together by brazing. However, the prior art still has defects.

[0003] GB874303A discloses a ceramic part for bonding with metals and alloys, having a metallized mixture forming a diffusion layer and firmly adhering to the ceramic part, the metallized mixture comprising a powder consisting of at least one metal selected from molybdenum, tungsten, rhenium and iron, and at least one oxide selected from oxides of chromium, titanium and niobium; the diffusion layer cannot effectively diffuse and bond with high-purity alumina ceramic with a purity of more than 99wt% because the main element is mainly in the form of metal, and is only suitable for bonding with ceramic with an alumina content of less than 99wt%, and the sintering temperature needs to reach more than 1500℃.

[0004] Moreover, the formula of the metal layer provided by the prior art will flow, exude and even lose in a high-vacuum and high-temperature environment, resulting in uneven or damaged contact surfaces, and a large decrease in thermal conductivity and bonding strength. SUMMARY

[0005] The application aims to provide a transition layer powder, a transition layer and a preparation method and application thereof, which improves the welding improvement effect of the transition layer powder as a brazing transition material by a specific component ratio, and especially improves the brazing effect between tungsten material and high-purity alumina ceramic.

[0006] To achieve the application purpose, the application adopts the following technical scheme:

[0007] In a first aspect, the application provides a transition layer powder, and the preparation raw material of the transition layer powder is composed of tungsten, manganese oxide, silicon dioxide and aluminum oxide.

[0008] The mass percentage of tungsten in the preparation raw material of the transition layer powder is more than 75wt%.

[0009] The mass ratio of the tungsten to the manganese oxide is 8:1 to 20:1.

[0010] The transition layer powder provided by the application is prepared from tungsten, manganese oxide, silicon dioxide and aluminum oxide, and the ratio of tungsten and manganese oxide is controlled, so that the transition layer with a tungsten skeleton structure having micro-pores can be formed on the high-purity alumina ceramic substrate in application, the copper-based solder is melted into the tungsten skeleton pores of the transition layer to form a tungsten-copper infiltration effect, and the effect of wetting the tungsten material is achieved, thereby improving the connection strength between the high-purity alumina ceramic substrate with a purity of 99wt% or more and the tungsten material.

[0011] In the application, the content of tungsten in the transition layer powder is controlled so that the transition layer powder can fully exert the tungsten-copper infiltration effect in application. Specifically, the mass percentage of tungsten in the preparation raw material of the transition layer powder is 75wt% or more, for example, it can be 75wt%, 78wt%, 80wt%, 82wt%, 85wt%, 88wt% or 90wt%, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0012] In the application, the mass ratio of tungsten to manganese oxide in the preparation raw material of the transition layer powder is 8:1 to 20:1, for example, it can be 8:1, 10:1, 12:1, 15:1, 16:1, 18:1 or 20:1, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0013] Preferably, the preparation raw material of the transition layer powder consists of 75-85wt% of tungsten, 4.5-7.5wt% of manganese oxide, 6.75-11.25wt% of silicon dioxide and 3.75-6.25wt% of aluminum oxide.

[0014] The mass percentage of tungsten in the preparation raw material of the transition layer powder is 75-85wt%, for example, it can be 75wt%, 78wt%, 80wt%, 82wt% or 85wt%, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0015] The mass percentage of manganese oxide in the preparation raw material of the transition layer powder is 4.5-7.5wt%, for example, it can be 4.5wt%, 5wt%, 5.5wt%, 6wt%, 6.5wt%, 7wt% or 7.5wt%, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0016] The mass percentage of the silicon dioxide in the raw material for preparing the transition layer powder is 6.75-11.25 wt%, for example, it can be 6.75 wt%, 7 wt%, 7.5 wt%, 8 wt%, 8.5 wt%, 9 wt%, 9.5 wt%, 10 wt%, 10.5 wt%, 11 wt% or 11.25 wt%, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0017] The mass percentage of the aluminum oxide in the raw material for preparing the transition layer powder is 3.75-6.25 wt%, for example, it can be 3.75 wt%, 4 wt%, 4.5 wt%, 5 wt%, 5.5 wt%, 6 wt% or 6.25 wt%, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0018] In a second aspect, the present application provides a method for preparing the transition layer powder of the first aspect, which comprises the following steps: mixing tungsten, manganese oxide, silicon dioxide and aluminum oxide according to the formula to obtain the transition layer powder.

[0019] Preferably, the mixing method comprises ball milling.

[0020] The grinding balls used in the ball milling of the second aspect of the present application include but are not limited to zirconia balls.

[0021] Preferably, the ball-to-material ratio of the ball milling is 1:1 to 1.5:1, for example, it can be 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1 or 1.5:1, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0022] The ball-to-material ratio is the mass ratio of the grinding balls to the grinding material.

[0023] Preferably, the ball milling time is 45 h to 48 h, for example, it can be 45 h, 45.5 h, 46 h, 46.5 h, 47 h, 47.5 h or 48 h, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0024] In a third aspect, the present application provides a transition layer, the raw material for preparing the transition layer comprises a binder and the transition layer powder of the first aspect.

[0025] The preparation raw material of the transition layer can form a tungsten skeleton structure transition layer with micro-pores on the high-purity alumina ceramic substrate by using the transition layer powder and the binder, which facilitates the copper-based solder to melt into the tungsten skeleton pores of the transition layer to form a tungsten-copper infiltration effect, and has a wetting effect on the tungsten material, thereby improving the connection strength between the high-purity alumina ceramic substrate with a purity of more than 99wt% and the tungsten material.

[0026] Preferably, the binder comprises an alcohol solvent and cellulose.

[0027] Illustratively, the alcohol solvent comprises but is not limited to terpineol.

[0028] The terpineol comprises any one or a combination of at least two of α-terpineol, β-terpineol or γ-terpineol, and a typical but non-limiting combination comprises a combination of α-terpineol and β-terpineol, a combination of β-terpineol and γ-terpineol, a combination of α-terpineol and γ-terpineol, or a combination of α-terpineol, β-terpineol and γ-terpineol.

[0029] Illustratively, the cellulose comprises but is not limited to ethyl cellulose.

[0030] Preferably, the binder comprises uniformly mixed alcohol solvent and cellulose.

[0031] The present application does not specifically limit the method of uniformly mixing the alcohol solvent and the cellulose, as long as uniform mixing can be achieved. Illustratively, the method of uniform mixing comprises water bath heating and ultrasonic treatment for 20h to 24h, under which condition uniform mixing of the alcohol solvent and the cellulose can be ensured.

[0032] Preferably, the binder comprises 5wt% to 15wt% of cellulose in terms of mass percentage, for example, it can be 5wt%, 6wt%, 8wt%, 10wt%, 12wt% or 15wt%, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0033] Preferably, the binder is 33% to 35% of the mass of the transition layer powder, for example, it can be 33%, 33.5%, 34%, 34.5% or 35%, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0034] In a fourth aspect, the present application provides a preparation method of the transition layer of the third aspect, which comprises the following steps:

[0035] (1) mixing the binder and the transition layer powder according to the formula amount to obtain a transition layer slurry;

[0036] (2) coating the transition layer slurry on the surface of the substrate, and sequentially drying and sintering to obtain the transition layer.

[0037] Preferably, the mixing method of step (1) comprises ball milling.

[0038] As a preferred technical solution of the preparation method, the ball milling device used in the mixing of step (1) is the same as the ball milling device used in the preparation of the transition layer powder. That is, the binder is added to the ball milling device used in the preparation of the transition layer powder to realize the mixing of the binder and the transition layer powder.

[0039] Preferably, the ball milling conditions of the mixing of step (1) are the same as the ball milling conditions of the preparation of the transition layer powder.

[0040] Preferably, the temperature of the drying of step (2) is 60-80°C, for example, it can be 60°C, 65°C, 70°C, 75°C or 80°C, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0041] Preferably, the time of the drying of step (2) is 10-12h, for example, it can be 10h, 10.5h, 11h, 11.5h or 12h, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0042] Preferably, the sintering of step (2) adopts a wet hydrogen atmosphere, and the water temperature is 30-35°C, for example, it can be 30°C, 31°C, 32°C, 33°C, 34°C or 35°C, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0043] Preferably, the sintering of step (2) is continuous sintering.

[0044] Preferably, the continuous sintering is carried out in a continuous sintering furnace.

[0045] Illustratively, along the movement direction of the sintered sample, the continuous sintering furnace comprises four temperature zones, namely a first temperature zone, a second temperature zone, a third temperature zone and a fourth temperature zone, and there are 8-9 sintering boats in each temperature zone, and a boat is pushed forward every 12-18 minutes.

[0046] The temperature of the first temperature zone is 450-500°C, for example, it can be 450°C, 460°C, 470°C, 480°C or 500°C, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0047] The temperature of the second temperature zone is 850-900°C, for example, it can be 850°C, 860°C, 880°C, 890°C or 900°C, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0048] The temperature of the third temperature zone is 1250℃ to 1300℃, for example, can be 1250℃, 1260℃, 1270℃, 1280℃ or 1300℃, but not limited to the listed values, other values not listed in the range of values are also applicable.

[0049] The temperature of the fourth temperature zone is 1450℃ to 1500℃, for example, can be 1450℃, 1460℃, 1480℃, 1490℃ or 1500℃, but not limited to the listed values, other values not listed in the range of values are also applicable.

[0050] When sintering in a continuous sintering furnace, the boat pushing speed is 12min / boat to 18min / boat, for example, can be 12min / boat, 14min / boat, 15min / boat, 16min / boat or 18min / boat, but not limited to the listed values, other values not listed in the range of values are also applicable.

[0051] Preferably, the thickness of the transition layer in step (2) is 30μm to 40μm, for example, can be 30μm, 32μm, 35μm, 38μm or 40μm, but not limited to the listed values, other values not listed in the range of values are also applicable.

[0052] In a fifth aspect, the present application provides an application of the transition layer powder of the first aspect, the application comprising: the transition layer powder is used for brazing connection of a ceramic substrate and a tungsten material.

[0053] Preferably, the application comprises the following steps:

[0054] (I) mixing the binder and the transition layer powder to obtain a transition layer slurry;

[0055] (II) coating the transition layer slurry on the surface of the ceramic substrate, and sequentially drying and sintering to obtain a transition layer;

[0056] (III) placing the copper-based brazing material between the transition layer and the tungsten material to form a sandwich structure, and then sintering under a reducing atmosphere.

[0057] The transition layer powder provided by the present application can form a transition layer with a tungsten skeleton structure with small pores by controlling the mass ratio of tungsten and manganese oxide therein, and using silicon dioxide and aluminum oxide, and then using a copper-based brazing material with excellent wettability with tungsten for tungsten-copper infiltration and brazing. This not only ensures the connection strength between the tungsten material and the ceramic substrate, but also ensures the high temperature stability and thermal conductivity between the two, thereby improving the connection strength between the high-purity alumina ceramic substrate with a purity of more than 99% and the tungsten material.

[0058] Preferably, the binder of step (I) comprises an alcohol solvent and cellulose.

[0059] Illustratively, the alcohol solvent comprises, but is not limited to, terpineol.

[0060] The terpineol comprises any one of alpha-terpineol, beta-terpineol or gamma-terpineol or a combination of at least two of them, typically but not limited to a combination of alpha-terpineol and beta-terpineol, beta-terpineol and gamma-terpineol, alpha-terpineol and gamma-terpineol, or a combination of alpha-terpineol, beta-terpineol and gamma-terpineol.

[0061] Illustratively, the cellulose comprises ethyl cellulose.

[0062] Preferably, the binder of step (I) comprises a homogenous mixture of alcohol solvent and cellulose.

[0063] Preferably, the binder of step (I) comprises 5wt% to 15wt% of cellulose, for example, it can be 5wt%, 6wt%, 8wt%, 10wt%, 12wt% or 15wt%, but is not limited to the listed values, other unlisted values within the range of values are also applicable.

[0064] Preferably, the binder of step (I) is 33% to 35% of the mass of the transition layer powder, for example, it can be 33%, 33.5%, 34%, 34.5% or 35%, but is not limited to the listed values, other unlisted values within the range of values are also applicable.

[0065] Preferably, the temperature of the drying of step (II) is 60°C to 80°C, for example, it can be 60°C, 65°C, 70°C, 75°C or 80°C, but is not limited to the listed values, other unlisted values within the range of values are also applicable.

[0066] Preferably, the time of the drying of step (II) is 10h to 12h, for example, it can be 10h, 10.5h, 11h, 11.5h or 12h, but is not limited to the listed values, other unlisted values within the range of values are also applicable.

[0067] Preferably, the sintering of step (II) is performed in a wet hydrogen atmosphere, the water temperature is 30°C to 35°C, for example, it can be 30°C, 31°C, 32°C, 33°C, 34°C or 35°C, but is not limited to the listed values, other unlisted values within the range of values are also applicable.

[0068] Preferably, the sintering of step (II) is continuous sintering.

[0069] Preferably, the continuous sintering is performed in a continuous sintering furnace.

[0070] Exemplarily, the continuous sintering furnace comprises 4 temperature zones, i.e. a first temperature zone, a second temperature zone, a third temperature zone and a fourth temperature zone, along the moving direction of the sintering samples, and each temperature zone has 8 to 9 sintering boats, and a boat is pushed forward every 12 to 18 minutes.

[0071] The temperature of the first temperature zone is 450 to 500°C, for example, it can be 450°C, 460°C, 470°C, 480°C or 500°C, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0072] The temperature of the second temperature zone is 850 to 900°C, for example, it can be 850°C, 860°C, 880°C, 890°C or 900°C, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0073] The temperature of the third temperature zone is 1250 to 1300°C, for example, it can be 1250°C, 1260°C, 1270°C, 1280°C or 1300°C, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0074] The temperature of the fourth temperature zone is 1450 to 1500°C, for example, it can be 1450°C, 1460°C, 1480°C, 1490°C or 1500°C, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0075] When sintering in the continuous sintering furnace, the pushing boat speed is 12 to 18 minutes per boat, for example, it can be 12 minutes per boat, 14 minutes per boat, 15 minutes per boat, 16 minutes per boat or 18 minutes per boat, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0076] Preferably, the thickness of the transition layer in step (II) is 30 to 40 μm, for example, it can be 30 μm, 32 μm, 35 μm, 38 μm or 40 μm, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0077] Exemplarily, the sintering in step (III) is carried out in a tube furnace.

[0078] Exemplarily, the gas used in the reducing atmosphere condition in step (III) includes but is not limited to hydrogen.

[0079] Preferably, in step (III), a molybdenum material tool is used to fix the formed sandwich structure during sintering.

[0080] Preferably, the sintering temperature of step (III) is 1100-1170°C, and the time is 5-15 minutes.

[0081] The sintering temperature of step (III) is 1100-1170°C, for example, it can be 1100°C, 1110°C, 1120°C, 1130°C, 1140°C, 1150°C, 1160°C or 1170°C, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0082] The sintering time of step (III) is 5-15 minutes, for example, it can be 5 minutes, 6 minutes, 8 minutes, 10 minutes, 12 minutes or 15 minutes, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0083] Compared with the prior art, the present application has the following beneficial effects:

[0084] (1) The preparation raw material of the transition layer powder provided by the present application uses tungsten, manganese oxide, silicon dioxide and aluminum oxide, and the ratio of tungsten and manganese oxide is controlled, so that a tungsten skeleton structure transition layer with micro-pores can be formed in application, which is convenient for copper-based solder to melt into the tungsten skeleton pores of the transition layer to form a tungsten-copper infiltration effect, and has a wetting effect on tungsten materials, thereby improving the connection strength between the high-purity alumina ceramic substrate with a purity of more than 99wt% and tungsten materials;

[0085] (2) When the transition layer powder provided by the present application is applied to the connection between a ceramic substrate and tungsten materials, a transition layer with a tungsten skeleton structure with micro-pores can be formed on the surface of the ceramic substrate, and then a copper-based solder with excellent wetting property to tungsten materials is used for tungsten-copper infiltration and brazing, which not only ensures the connection strength between the tungsten materials and the ceramic substrate, but also ensures the high-temperature stability and thermal conductivity between the two, thereby improving the connection strength between the high-purity alumina ceramic substrate with a purity of more than 99% and tungsten materials. BRIEF DESCRIPTION OF DRAWINGS

[0086] Figure 1 It is a schematic diagram of the cross section of the transition layer formed on the surface of the Al2O3 ceramic substrate in application example 3;

[0087] Figure 2 It is a schematic diagram of the cross section of the Al2O3 ceramic substrate and tungsten materials after welding in application example 3;

[0088] Figure 3 It is an image of the transition layer obtained in comparative application example 1 showing bubbling and peeling phenomenon;

[0089] Figure 4A schematic diagram of the cross section of the Al2O3 ceramic substrate after welding with tungsten material in Comparative Application 1 is shown in Figure 1.

[0090] Figure 5 A schematic diagram of the cross section of the Al2O3 ceramic substrate after welding with tungsten material in Comparative Application 2 is shown in Figure 2. DETAILED DESCRIPTION

[0091] The technical solutions of the present application will be further illustrated by specific embodiments. Those skilled in the art should understand that the embodiments are only used to help understand the present application and should not be regarded as specific limitations of the present application.

[0092] Embodiment 1

[0093] The present embodiment provides a transition layer powder, the preparation raw materials of the transition layer powder consist of 85.4wt% tungsten, 4.27wt% manganese oxide, 6.75wt% silicon dioxide and 3.58wt% aluminum oxide, in terms of mass percentage.

[0094] The preparation method of the transition layer powder in the present embodiment includes the following steps: ball-milling tungsten, manganese oxide, silicon dioxide and aluminum oxide according to the formula amount to obtain the transition layer powder.

[0095] The ball-to-material ratio of ball-milling is 1.2:1, and the time is 46h.

[0096] Embodiment 2

[0097] The present embodiment provides a transition layer powder, the preparation raw materials of the transition layer powder consist of 80wt% tungsten, 10wt% manganese oxide, 6.75wt% silicon dioxide and 3.25wt% aluminum oxide, in terms of mass percentage.

[0098] The preparation method of the transition layer powder in the present embodiment includes the following steps: ball-milling tungsten, manganese oxide, silicon dioxide and aluminum oxide according to the formula amount to obtain the transition layer powder.

[0099] The ball-to-material ratio of ball-milling is 1.2:1, and the time is 46h.

[0100] Embodiment 3

[0101] The present embodiment provides a transition layer powder, the preparation raw materials of the transition layer powder consist of 75wt% tungsten, 7.5wt% manganese oxide, 11.25wt% silicon dioxide and 6.25wt% aluminum oxide, in terms of mass percentage.

[0102] The preparation method of the transition layer powder in the present embodiment includes the following steps: ball-milling tungsten, manganese oxide, silicon dioxide and aluminum oxide according to the formula amount to obtain the transition layer powder.

[0103] The ball-to-material ratio of the ball milling is 1.2:1, and the time is 46 h.

[0104] Example 4

[0105] The transition layer powder provided in this example is prepared from 85 wt% tungsten, 4.5 wt% manganese oxide, 6.75 wt% silicon dioxide, and 3.75 wt% aluminum trioxide.

[0106] The preparation method of the transition layer powder in this example includes the following steps: ball milling tungsten, manganese oxide, silicon dioxide, and aluminum trioxide in the formula amount to obtain the transition layer powder.

[0107] The ball-to-material ratio of the ball milling is 1.2:1, and the time is 46 h.

[0108] Example 5

[0109] The transition layer powder provided in this example is prepared from 80 wt% tungsten, 5 wt% manganese oxide, 10 wt% silicon dioxide, and 5 wt% aluminum trioxide.

[0110] The preparation method of the transition layer powder in this example includes the following steps: ball milling tungsten, manganese oxide, silicon dioxide, and aluminum trioxide in the formula amount to obtain the transition layer powder.

[0111] The ball-to-material ratio of the ball milling is 1:1, and the time is 48 h.

[0112] Example 6

[0113] The transition layer powder provided in this example is prepared from 80 wt% tungsten, 5 wt% manganese oxide, 10 wt% silicon dioxide, and 5 wt% aluminum trioxide.

[0114] The preparation method of the transition layer powder in this example includes the following steps: ball milling tungsten, manganese oxide, silicon dioxide, and aluminum trioxide in the formula amount to obtain the transition layer powder.

[0115] The ball-to-material ratio of the ball milling is 1.5:1, and the time is 45 h.

[0116] Comparative Example 1

[0117] The transition layer powder provided in this example is prepared from 70 wt% tungsten, 10.6 wt% manganese oxide, 13.8 wt% silicon dioxide, and 5.6 wt% aluminum trioxide.

[0118] The preparation method of the transition layer powder in the present comparative example comprises the following steps: ball-milling tungsten, manganese oxide, silicon dioxide and aluminum oxide in the formula amount to obtain the transition layer powder.

[0119] The ball-to-material ratio of the ball-milling is 1.2:1, and the time is 46 h.

[0120] Comparative Example 2

[0121] The present comparative example provides a transition layer powder, which is composed of 90 wt% of tungsten, 3 wt% of manganese oxide, 4.5 wt% of silicon dioxide and 2.5 wt% of aluminum oxide in terms of mass percentage.

[0122] The preparation method of the transition layer powder in the present comparative example comprises the following steps: ball-milling tungsten, manganese oxide, silicon dioxide and aluminum oxide in the formula amount to obtain the transition layer powder.

[0123] The ball-to-material ratio of the ball-milling is 1.2:1, and the time is 46 h.

[0124] Application Example 1

[0125] The present application example provides an application of the transition layer powder provided in Example 1, which is the application of the transition layer powder to the brazing connection of an Al2O3 ceramic substrate (purity 99 wt%) and tungsten material, comprising the following steps:

[0126] (I) Ball-milling the binder and the transition layer powder to obtain a transition layer slurry; the binder is 34% of the mass of the transition layer powder;

[0127] The ball-milling is continued in the ball-milling device used in Example 1, and the ball-milling time is 48 h;

[0128] The binder is prepared by the following steps: mixing α-terpineol 90% and ethyl cellulose (Macklin, AR) 10% in terms of mass percentage, water bath heating and ultrasonic treatment for 24 h to uniformly mix the terpineol and the ethyl cellulose;

[0129] (II) The transition layer slurry is coated on the surface of the Al2O3 ceramic substrate, and is sequentially dried and sintered to obtain a transition layer with a thickness of 35 μm;

[0130] The drying temperature is 70°C, and the time is 11 h;

[0131] The sintering is continuous sintering, which is carried out in a continuous sintering furnace, and the sintering is carried out in a wet hydrogen atmosphere with a water temperature of 32 DEG C; the continuous sintering furnace comprises four temperature zones along the movement direction of the sintered sample, which are a first temperature zone, a second temperature zone, a third temperature zone and a fourth temperature zone, respectively, and there are eight sintering boats in each temperature zone, and a boat is pushed forward every 15 minutes; the temperature of the first temperature zone is 480 DEG C, the temperature of the second temperature zone is 880 DEG C, the temperature of the third temperature zone is 1280 DEG C, and the temperature of the fourth temperature zone is 1480 DEG C;

[0132] (III) placing the copper-based brazing filler metal between the transition layer and the tungsten material to form a sandwich structure, fixing the sandwich structure by using a tungsten material tooling, and placing the sandwich structure in a tube furnace to perform sintering, thereby completing the brazing and infiltration connection of the Al2O3 ceramic substrate and the tungsten material; the sintering atmosphere is a hydrogen atmosphere, the sintering temperature is 1150 DEG C, and the time is 10 minutes.

[0133] Application Example 2

[0134] In this application example, a kind of application of transition layer powder is provided, in addition to the transition layer powder provided in Example 2, the rest is the same as Application Example 1.

[0135] In this application example, ball milling is continued in the ball milling device used in Example 2.

[0136] Application Example 3

[0137] In this application example, a kind of application of transition layer powder is provided, in addition to the transition layer powder provided in Example 3, the rest is the same as Application Example 1.

[0138] In this application example, ball milling is continued in the ball milling device used in Example 3.

[0139] In this application example, the cross-sectional schematic diagram of the transition layer formed on the surface of the Al2O3 ceramic substrate is as shown in Figure 1 Figure 1 The area ① in represents the Al2O3 ceramic substrate, the area ② represents the diffusion interface of the glass phase and the ceramic matrix in the transition layer, the area ③ represents the jagged connection of the glass phase and the tungsten skeleton in the transition layer, and the area ④ represents the tungsten skeleton in the transition layer.

[0140] Figure 1 As can be seen from , the transition layer in this application example not only ensures the connectivity of the transition layer and the Al2O3 ceramic substrate, but also provides the outer surface of the tungsten skeleton structure.

[0141] Figure 2 In this application example, the cross-sectional schematic diagram of the Al2O3 ceramic substrate and the tungsten material after welding is as shown in Figure 2 ​It can be seen that the copper filler melts at high temperature, penetrates into the tungsten skeleton, fills the gaps of the tungsten skeleton, and forms a copper layer on the surface, which facilitates the wetting connection between the copper layer and the tungsten material.

[0142] Application Example 4

[0143] The application example provides an application of the transition layer powder provided in Embodiment 3, and the application is that the transition layer powder is used for brazing connection of an Al2O3 ceramic substrate (purity 99wt%) and a tungsten material, and includes the following steps.

[0144] (I) Ball-milling the binder and the transition layer powder to obtain a transition layer slurry; the binder is 33% of the mass of the transition layer powder;

[0145] The ball-milling is continuously performed in the ball-milling device used in Embodiment 3, and the ball-milling time is 48h;

[0146] The binder is prepared by the following steps: mixing α-terpineol 95% and ethyl cellulose (Macklin, AR) 5% according to the mass percentage, water bath heating and ultrasonic treatment for 24h to uniformly mix the terpineol and the ethyl cellulose;

[0147] (II) Coating the transition layer slurry on the surface of the Al2O3 ceramic substrate, and sequentially drying and sintering to obtain a transition layer with a thickness of 35μm;

[0148] The drying temperature is 60℃, and the time is 12h;

[0149] The sintering is continuous sintering, which is performed in a continuous sintering furnace; the sintering adopts a wet hydrogen atmosphere, and the water temperature is 35℃; along the movement direction of the sintered sample, the continuous sintering furnace includes four temperature zones, which are a first temperature zone, a second temperature zone, a third temperature zone and a fourth temperature zone; there are 8 sintering boats in each temperature zone, and one boat is pushed forward every 18min; the temperature of the first temperature zone is 450℃, the temperature of the second temperature zone is 850℃, the temperature of the third temperature zone is 1250℃, and the temperature of the fourth temperature zone is 1450℃;

[0150] (III) Placing the copper-based brazing filler on the transition layer and the tungsten material to form a sandwich structure, fixing the formed sandwich structure by using a tungsten material tooling, and placing the sandwich structure in a tube furnace for sintering to complete the brazing and infiltration connection of the Al2O3 ceramic substrate and the tungsten material; the sintering atmosphere is a hydrogen atmosphere, the sintering temperature is 1100℃, and the time is 15min.

[0151] Application Example 5

[0152] The application example provides an application of the transition layer powder provided in Embodiment 3, and the application is that the transition layer powder is used for brazing connection of an Al2O3 ceramic substrate (purity 99wt%) and a tungsten material, and includes the following steps.

[0153] (I) Ball-milling the binder with the transition layer powder to obtain a transition layer slurry; the binder is 35% of the mass of the transition layer powder;

[0154] The ball-milling is continued in the ball-milling device used in Example 3, and the ball-milling time is 48 h.

[0155] The binder is prepared by mixing α-terpineol 85% and ethyl cellulose (Macklin, AR) 15% by mass percentage, water bath heating and ultrasonic treatment for 24 h to uniformly mix the terpineol and ethyl cellulose.

[0156] (II) Coating the transition layer slurry on the surface of the Al2O3 ceramic substrate, and sequentially drying and sintering to obtain a transition layer with a thickness of 35 μm;

[0157] The drying temperature is 80°C, and the time is 10 h.

[0158] The sintering is continuous sintering, which is performed in a continuous sintering furnace. The sintering uses a wet hydrogen atmosphere, and the water temperature is 30°C. Along the movement direction of the sintered sample, the continuous sintering furnace includes four temperature zones, namely, a first temperature zone, a second temperature zone, a third temperature zone and a fourth temperature zone. There are 9 sintering boats in each temperature zone, and a boat is pushed forward every 12 min. The temperature of the first temperature zone is 500°C, the temperature of the second temperature zone is 900°C, the temperature of the third temperature zone is 1300°C, and the temperature of the fourth temperature zone is 1500°C.

[0159] (III) Placing the copper-based brazing filler metal between the transition layer and the tungsten material to form a sandwich structure, fixing the sandwich structure using a tungsten material tool, and placing the sandwich structure in a tube furnace for sintering to complete the brazing and infiltration connection of the Al2O3 ceramic substrate and the tungsten material. The sintering atmosphere is a hydrogen atmosphere, the sintering temperature is 1170°C, and the time is 5 min.

[0160] Application Example 6

[0161] This application example provides an application of a transition layer powder. Except that the transition layer powder is the transition layer powder provided in Example 4, the rest is the same as Application Example 1.

[0162] In this application example, the ball-milling is continued in the ball-milling device used in Example 4.

[0163] Application Example 7

[0164] This application example provides an application of a transition layer powder. Except that the transition layer powder is the transition layer powder provided in Example 5, the rest is the same as Application Example 1.

[0165] In this application example, the ball-milling is continued in the ball-milling device used in Example 5.

[0166] Application Example 8

[0167] This application example provides an application of a transition layer powder, except that the transition layer powder is the same as that provided in Example 6, and everything else is the same as in Application Example 1.

[0168] In this application example, ball milling and mixing continue in the ball milling apparatus used in Example 6.

[0169] Comparative Application Example 1

[0170] This comparative application example provides an application of a transition layer powder, which is the same as that in application example 1, except that the transition layer powder is the same as that provided in comparative example 1.

[0171] In this comparative application example, ball milling and mixing continued in the ball milling apparatus used in Comparative Example 1.

[0172] The transition layer obtained in this comparative application example is as follows: Figure 3 As shown, by Figure 3 It is evident that blistering and peeling occur; moreover, there is a clear delamination between the brazed transition layer and the ceramic substrate (see [reference]). Figure 4 There is almost no connection strength.

[0173] Comparative Application Example 2

[0174] This comparative application example provides an application of a transition layer powder, which is the same as that in application example 1, except that the transition layer powder is the same as that provided in comparative example 2.

[0175] In this comparative application example, ball milling and mixing continued in the ball milling apparatus used in Comparative Example 2.

[0176] The cross-sectional view of the transition layer obtained in this comparative application example is as follows: Figure 5 As shown, by Figure 5 It can be seen that the transition layer in this comparative application example has too many pores, resulting in a low bonding strength between the final ceramic substrate and the tungsten material.

[0177] Performance Characterization

[0178] In corresponding use cases 1-8 and comparative application example 1-2, the welding strength of the brazed Al2O3 ceramic substrate and tungsten material was tested. The test method was carried out using a universal testing machine in accordance with GB / T 13683-1992 "Pin Shear Test Method". Each test was performed 3 times, and the test results were taken as the average of the 3 tests, as shown in Table 1.

[0179] Table 1

[0180] Cross-sectional area (mm 2 )]]> Tensile force (KN) Shear strength (MPa) Application Example 1 134 5.32 39.70 Application Example 2 134 3.23 24.10 Application Example 3 134 13.34 99.57 Application Example 4 134 13.41 100.1 Application Example 5 134 14.42 107.6 Application Example 6 134 14.38 107.3 Application Example 7 134 13.26 98.95 Application Example 8 134 13.18 98.36 Comparative Application Example 1 134 0.3 2.23 Comparative Application Example 2 134 1.4 10.45

[0181] From the data provided by Table 1, when the composition of the transition layer powder satisfies that the mass percentage of tungsten is 75wt% or more, and the mass ratio of tungsten to manganese oxide is 8:1 to 20:1, the shear strength between the high-purity alumina ceramic substrate with a purity of 99wt% or more and the tungsten material can reach 24MPa or more, which is much higher than 2.23MPa in the comparative application example 1 and 10.45MPa in the comparative application example 2; further, when the composition of the transition layer powder satisfies that the preparation raw material is composed of 75-85wt% of tungsten, 4.5-7.5wt% of manganese oxide, 6.75-11.25wt% of silicon dioxide and 3.75-6.25wt% of aluminum trioxide, the shear strength between the high-purity alumina ceramic substrate with a purity of 99wt% or more and the tungsten material can reach 98MPa or more.

[0182] In summary, the preparation raw material of the transition layer powder provided by the present application uses tungsten, manganese oxide, silicon dioxide and aluminum trioxide, and the ratio of tungsten to manganese oxide is controlled, so that when applied, the transition layer with a tungsten skeleton structure having a small pore can be formed on the high-purity alumina ceramic substrate, which facilitates the copper-based brazing filler to melt into the tungsten skeleton pores of the transition layer to form a tungsten-copper infiltration effect, and has the effect of wetting the tungsten material, thereby improving the connection strength between the high-purity alumina ceramic substrate with a purity of 99wt% or more and the tungsten material to 20MPa or more, and in the preferred embodiment, the connection strength can be increased to 98MPa or more.

[0183] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and those skilled in the art should understand that any changes or replacements within the technical scope disclosed by the present application can be easily thought out by those skilled in the art, and all fall within the protection scope and disclosure scope of the present application.

Claims

1. Use of a transition layer powder, characterized in that The application comprises the following steps: (I) mixing the binder with the transition layer powder to obtain a transition layer slurry; (II) coating the transition layer slurry on the surface of the ceramic substrate, and sequentially drying and sintering to obtain the transition layer; (III) placing the copper-based brazing filler metal between the transition layer and the tungsten material to form a sandwich structure, and then sintering under a reducing atmosphere; The transition layer powder is used for brazing connection of the ceramic substrate and the tungsten material; The preparation raw material of the transition layer powder comprises tungsten, manganese oxide, silicon dioxide and aluminum oxide; The mass percentage of tungsten in the preparation raw material of the transition layer powder is 75 wt% or more. The mass ratio of tungsten to manganese oxide is 8:1 to 20:

1.

2. Use according to claim 1, characterized in that, The preparation raw material of the transition layer powder comprises 75-85 wt% of tungsten, 4.5-7.5 wt% of manganese oxide, 6.75-11.25 wt% of silicon dioxide and 3.75-6.25 wt% of aluminum oxide.

3. Use according to claim 1, characterized in that, The preparation method of the transition layer powder comprises the following steps: mixing tungsten, manganese oxide, silicon dioxide and aluminum oxide according to the formula amount to obtain the transition layer powder.

4. Use according to claim 3, characterized in that, The mixing method comprises ball milling.

5. Use according to claim 4, characterized in that, The ball milling ratio is 1:1 to 1.5:

1.

6. Use according to claim 4, characterized in that, The ball milling time is 45 h to 48 h.

7. Use according to claim 1, characterized in that, The transition layer powder is prepared into a transition layer; the preparation raw material of the transition layer comprises a binder and the transition layer powder of claim 1 or 2.

8. Use according to claim 7, characterized in that, The preparation method of the transition layer comprises the following steps: (1) mixing the binder with the transition layer powder according to the formula amount to obtain a transition layer slurry; (2) coating the transition layer slurry on the surface of the substrate, and sequentially drying and sintering to obtain the transition layer.

9. Use according to claim 8, characterized in that, The mixing method of step (1) comprises ball milling.

10. The use according to claim 1, characterized in that, The binder of step (I) comprises an alcohol solvent and cellulose.

11. Use according to claim 10, characterized in that, The binder of step (I) comprises uniformly mixed alcohol solvent and cellulose.

12. The use according to claim 10, characterized in that, The binder of step (I) comprises 5 wt% to 15 wt% of cellulose.

13. The use according to claim 1, characterized in that, The binder of step (I) is 33% to 35% of the mass of the transition layer powder.

14. The use according to claim 1, characterized in that, The drying temperature of step (II) is 60°C to 80°C.

15. The use according to claim 1, characterized in that, The drying time of step (II) is 10 h to 12 h.

16. The use according to claim 1, characterized in that, The sintering of step (II) adopts a wet hydrogen atmosphere, and the water temperature is 30°C to 35°C.

17. The use according to claim 1, characterized in that, The sintering temperature of step (III) is 1100°C to 1170°C, and the time is 5 min to 15 min.

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