A method for connecting ceramic or ceramic-based composite materials and metal materials with inactive brazing filler metal

Abstract

The present invention belongs to the field of brazing welding technology, and specifically relates to a method for connecting ceramics or ceramic-based composite materials with metal materials using an inactive brazing filler metal. The method first pre-treats the substrate to be welded, then adds cerium oxide powder to a nickel plating solution to form a composite coating on the surface of a TiC-Ni metal ceramic, and then brazes the TiC-Ni metal ceramic with the composite coating using an inactive Ag-Cu brazing filler metal to achieve connection with 304 stainless steel. After welding, this method can enhance the interface bonding strength and the mechanical properties of the joint, thereby improving the current problem of large residual stress and low connection strength of TiC-Ni ceramic joints, and has very good development prospects.

Description

Technical Field

[0001] The invention belongs to the technical field of brazing and welding, and particularly relates to a method for connecting ceramic or ceramic-based composite materials and metal materials using an inactive brazing filler metal. Background Art

[0002] TiC-Ni cermets offer excellent properties such as high hardness, low specific gravity, and high wear and corrosion resistance, as well as significant resource advantages (global Ti reserves are nearly 70 times that of W). Consequently, they hold broad application prospects in cutting tools, molds, and wear- and corrosion-resistant parts. However, cermets lack strength, toughness, and processing properties. Joining them with tougher metals like steel, which can withstand significant impact loads, can maximize their respective strengths.

[0003] Currently, brazing is the most common method for joining ceramics or ceramic-based composites to metals. The challenges faced in joining TiC-Ni cermets to metals include: 1) poor surface wettability of inactive brazing fillers when wetting the cermet; 2) controlling the formation of brittle compounds at the interface; and 3) reducing residual stresses caused by differences in the thermal expansion coefficients of dissimilar materials to improve joint performance. In the field of ceramic-metal joining, researchers have proposed several solutions to address similar challenges. Chinese Patent Application No. CN202210462646.6 describes a method for joining AlN ceramics and Cu by adding rare earth oxides to an active brazing filler metal. This method successfully achieves a gradient transition in the thermal expansion coefficient of the joint by adding rare earth oxides. Furthermore, the uniform dispersion of the rare earth oxides in the brazing seam refines the Ag-Cu eutectic phase in the brazing filler metal, improving the mechanical properties of the brazed joint. However, the uneven distribution of brittle compounds generated by the reaction of active elements in the brazing filler metal can still reduce joint performance. Chinese Patent Application No. CN202210428629.0 describes a method for brazing alumina ceramics after metallization. This method involves pre-treating the substrate surface, electroplating Ni, and then welding the substrate. After the ceramic is metallized, it achieves good brazing performance. However, the pre-treatment process is complex and time-consuming. Therefore, it is urgent to develop a new method to solve the above problems. Summary of the Invention

[0004] The purpose of the present invention is to solve the deficiencies of the prior art and provide a method for connecting ceramic or ceramic-based composite materials with metal materials using an inactive brazing filler metal. Specifically, the following technical solutions are adopted:

[0005] A method for connecting ceramic or ceramic-based composite materials and metal materials using an inactive brazing filler metal comprises the following steps:

[0006] Step 1: Grind the ceramic material to be welded, the metal material to be welded, and the Ag-Cu foil solder with sandpaper, and then clean them with acetone for 10 to 20 minutes to obtain clean ceramic material to be welded, metal material to be welded, and Ag-Cu foil solder;

[0007] Step 2: Immerse the ceramic material to be welded in the electroplating solution as the cathode and the nickel metal as the anode. After connecting the DC current, the current is 1-2A / dm at 50℃. 2 Electroplating for 10 minutes under the conditions, a metal nickel layer is deposited on the prefabricated ceramic to obtain a nickel-plated metal ceramic; the electroplating solution includes: NiSO4 solution, NiCl2 solution, H3BO4 solution, CH3(CH2) 11 OSO3Na solution, cerium oxide and water;

[0008] Step 3: stack the clean metal material to be welded, Ag-Cu foil brazing filler metal and nickel-plated metal ceramic in order from bottom to top, and fix them to obtain the workpiece to be welded; place the workpiece to be welded in a vacuum brazing furnace, heat it to 790°C to 900°C at a heating rate of 1°C / min to 50°C / min, keep it warm for 5min to 30min, then cool it to 400°C at a cooling rate of 2°C / min to 20°C / min, and then cool it to 150°C with the furnace. Open the furnace and take out the workpiece, thus obtaining the brazing of ceramic or ceramic-based composite material and metal material.

[0009] This invention innovatively proposes adding cerium oxide powder to a nickel plating solution to form a composite coating on the surface of a cermet. The composite coating is then brazed with an inactive Ag-Cu eutectic filler metal to achieve a connection to the metal. This method simplifies the coating preparation process; the rare earth element-containing coating improves the wettability of the inactive AgCu filler metal on the cermet surface, refines the brazing seam grain structure, and inhibits the filler metal from dissolving the coating. The inactive AgCu filler metal reacts with the base metal to form a solid solution, inhibiting the formation of brittle compounds at the interface. Ultimately, this method effectively improves the mechanical properties of the TiC-Ni cermet-steel joint.

[0010] As a further preferred embodiment, the above step further includes a pretreatment step before step 2, wherein the metal material to be welded is subjected to roughening-cleaning-sensitization-cleaning-activation-cleaning. The specific process of the roughening-cleaning-sensitization-cleaning-activation-cleaning is as follows:

[0011] First, place the clean ceramic material to be welded in 10% hydrofluoric acid for 15 minutes and rinse with distilled water; then weigh 10g of stannous chloride, measure 92mL of hydrochloric acid, dilute to 1L with water, add the roughened ceramic material, sensitize at room temperature for 30 minutes, and rinse with distilled water 2-3 times after sensitization; finally, weigh 0.5g of palladium dichloride, 20g of boric acid, measure 0.5mL of hydrochloric acid, dilute to 1L with water, add the sensitized ceramic, activate at room temperature for 30 minutes, and rinse with distilled water 2-3 times. In the above steps, roughening is to give the ceramic surface a certain degree of roughness and improve the surface adhesion of the coating; sensitization is to form tiny condensation nuclei on the surface of the plated part, which is conducive to the precipitation of the plated material; activation is to form a catalytic film on the surface of the plated part to enhance the bonding strength of the coating; and cleaning is to wash away the residual chemical reagents from the previous step.

[0012] As a further preferred embodiment, the acetone cleaning time in step 1 is 15 minutes.

[0013] As a further preferred embodiment, the current in the above step 2 is 2 A / dm.

[0014] As a further preferred embodiment, the concentrations of the plating solution components in step 3 are as follows:

[0015] The concentration of NiSO4 solution is 280g / L, the concentration of NiCl2 solution is 50g / L, the concentration of H3BO4 solution is 35g / L, and the concentration of CH3(CH2) 11 The concentration of the OSO3Na solution is 1 g / L, and the cerium oxide content is 1%-10%. More preferably, the cerium oxide content is 5%.

[0016] As a further preferred embodiment, in step 3, the temperature is increased to 900°C at a rate of 15°C / min. The temperature is decreased to 400°C at a rate of 10°C / min. The holding time in step 3 is 10 minutes. In the above steps, excessively high temperatures and excessively high heating rates can increase thermal stress within the brazing seam. Therefore, the present invention controls both the temperature and heating rate within a reasonable range, ensuring a single variable.

[0017] The present invention provides a composite coating that, compared to existing single-Ni plating systems and active brazing filler metal systems, only incorporates a certain amount of rare earth oxides. This allows successful brazing of TiC-Ni cermets and 304 stainless steel using conventional Ag-Cu eutectic filler metals, resulting in high-strength brazed joints. This addresses the current challenges of high residual stress and low joint strength in TiC-Ni ceramic joints. Furthermore, the composite coating provided by the present invention features a simple preparation process, eliminating the need for expensive equipment and complex procedures. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 Shown is the SEM image of the joint provided in Example 2 of the present invention. DETAILED DESCRIPTION

[0020] To facilitate understanding of the present application, a more comprehensive description of the present application will be provided below with reference to the accompanying drawings. The drawings illustrate several embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present disclosure.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The term "and / or" as used herein includes any and all combinations of one or more of the relevant listed items.

[0022] In this document, unless otherwise specified, the term "%" refers to "mass %"; the term "μg / mL" refers to: micrograms per milliliter. In this document, unless otherwise specified, the term "%" refers to the total weight of the composition of the present application.

[0023] In this document, all defined ranges include each specific range within the given range and the combination of sub-ranges between the given ranges. For example, the range of 1 to 5 specifically includes 1, 2, 3, 4, and 5, and also includes sub-ranges such as 2 to 5, 3 to 5, 2 to 3, 2 to 4, 1 to 4, etc.

[0024] Example 1

[0025] A method for connecting ceramic or ceramic-based composite materials and metal materials using an inactive brazing filler metal, the specific steps of which are as follows:

[0026] Step 1: Pre-treat the substrate to be welded: polish the base material (15mm×25mm×3mm 304 stainless steel and 5mm×5mm×3mm TiC-Ni metal ceramic) with sandpaper, and then clean it with acetone for 15 minutes to obtain clean TiC-Ni metal ceramic, 304 stainless steel and Ag-Cu foil solder to be welded;

[0027] Step 2: Pretreat the TiC-Ni metal ceramic to be welded: (roughening) Add 25mL of 40% hydrofluoric acid and dilute it with water to 100mL, then add the TiC-Ni metal ceramic to be welded and roughen it for 15min, and rinse with distilled water; (sensitization) Weigh 10g of stannous chloride and 92mL of hydrochloric acid, add the two chemicals to a beaker, dilute to 1L, add the roughened ceramic to the beaker, sensitize at room temperature for 30min, and rinse with distilled water 3 times after sensitization; (activation) Weigh 0.5g of palladium dichloride, 20g of boric acid, and 0.5mL of hydrochloric acid, place the above chemicals in a 1L beaker and dilute them to 1L, add the sensitized ceramic to the beaker, activate at room temperature for 30min, and rinse with distilled water 3 times.

[0028] Step 3: Prepare the composite coating: Immerse the TiC-Ni metal ceramic pretreated in step 2 into the electroplating solution as the cathode and nickel as the anode. Connect the DC current at 50°C and 2A / dm 2 Under the conditions of 400 nm, a nickel layer is deposited on the preform to obtain a nickel-plated cermet (nickel-plated TiC-Ni cermet), wherein the electroplating solution comprises: a NiSO4 solution with a concentration of 280 g / L, a NiCl2 solution with a concentration of 50 g / L, an H3BO4 solution with a concentration of 35 g / L, and a CH3(CH2) solution with a concentration of 1 g / L. 11 OSO3Na solution, 1% cerium oxide, and distilled water were added to 200 mL.

[0029] Step 4: Use brazing to weld the two substrates to be welded: stack clean 304 stainless steel, Ag-Cu foil brazing material, and nickel-plated TiC-Ni metal ceramic in order from bottom to top, fix them to obtain the welded parts, place the welded parts in a vacuum brazing furnace, heat them to 800℃ at a heating rate of 15℃ / min, keep them warm for 10 minutes, then cool them to 400℃ at a cooling rate of 10℃ / min, and then cool them to 150℃ with the furnace. Open the furnace and take out the parts, thus completing the brazing of nickel-plated TiC-Ni metal ceramic and 304 stainless steel. The tensile shear strength was tested by a universal tensile machine and was 57MPa.

[0030] Example 2

[0031] A method for connecting ceramic or ceramic-based composite materials and metal materials using an inactive brazing filler metal, the specific steps of which are as follows:

[0032] Step 1: Pre-treat the substrate to be welded: polish the base material (15mm×25mm×3mm 304 stainless steel and 5mm×5mm×3mm TiC-Ni metal ceramic) with sandpaper, and then clean it with acetone for 15 minutes to obtain clean TiC metal ceramic, 304 stainless steel and Ag-Cu foil solder to be welded;

[0033] Step 2: Pretreat the TiC-Ni metal ceramic to be welded: (roughening) Add 25mL of 40% hydrofluoric acid and dilute it with water to 100mL, then add the TiC-Ni metal ceramic to be welded and roughen it for 15min, and rinse with distilled water; (sensitization) Weigh 10g of stannous chloride and 92mL of hydrochloric acid, add the two chemicals to a beaker, dilute to 1L, add the roughened ceramic to the beaker, sensitize at room temperature for 30min, and rinse with distilled water 3 times after sensitization; (activation) Weigh 0.5g of palladium dichloride, 20g of boric acid, and 0.5mL of hydrochloric acid, place the above chemicals in a 1L beaker and dilute them to 1L, add the sensitized ceramic to the beaker, activate at room temperature for 30min, and rinse with distilled water 3 times.

[0034] Step 3: Prepare the composite coating: Immerse the TiC-Ni metal ceramic pretreated in step 2 into the electroplating solution as the cathode and nickel as the anode. Connect the DC current at 50°C and 2A / dm 2 Under the conditions of 400 nm, a nickel layer is deposited on the preform to obtain a nickel-plated cermet (nickel-plated TiC-Ni cermet), wherein the electroplating solution comprises: a NiSO4 solution with a concentration of 280 g / L, a NiCl2 solution with a concentration of 50 g / L, an H3BO4 solution with a concentration of 35 g / L, and a CH3(CH2) solution with a concentration of 1 g / L. 11 OSO3Na solution, cerium oxide with a content of 5%, and distilled water are added to 200mL.

[0035] Step 4: Braze the two substrates to be welded: Clean 304 stainless steel, Ag-Cu brazing filler metal foil, and nickel-plated TiC-Ni cermet are stacked in order from bottom to top, secured, and then placed in a vacuum brazing furnace. The temperature is raised to 800°C at a heating rate of 15°C / min, held for 10 minutes, then cooled to 400°C at a cooling rate of 10°C / min. The furnace is then opened and the brazing of the nickel-plated TiC-Ni cermet to the 304 stainless steel is complete. The tensile shear strength tested using a universal tensile tester is 116 MPa.

[0036] Example 3

[0037] A method for connecting ceramic or ceramic-based composite materials and metal materials using an inactive brazing filler metal, the specific steps of which are as follows:

[0038] Step 1: Pre-treat the substrate to be welded: polish the base material (15mm×25mm×3mm 304 stainless steel and 5mm×5mm×3mm TiC-Ni metal ceramic) with sandpaper, and then clean it with acetone for 15 minutes to obtain clean TiC-Ni metal ceramic, 304 stainless steel and Ag-Cu foil solder to be welded;

[0039] Step 2: Pre-treat the TiC metal ceramic to be welded: (roughening) Add 25mL of 40% hydrofluoric acid and dilute it with water to 100mL, then add the TiC-Ni metal ceramic to be welded and roughen it for 15min, and rinse with distilled water; (sensitization) Weigh 10g of stannous chloride and 92mL of hydrochloric acid, add the two chemicals to a beaker, dilute to 1L, add the roughened ceramic to the beaker, sensitize at room temperature for 30min, and rinse with distilled water 3 times after sensitization; (activation) Weigh 0.5g of palladium dichloride, 20g of boric acid, and 0.5mL of hydrochloric acid, place the above chemicals in a 1L beaker and dilute them to 1L, add the sensitized ceramic to the beaker, activate at room temperature for 30min, and rinse with distilled water 3 times.

[0040] Step 3: Prepare the composite coating: Immerse the TiC-Ni metal ceramic pretreated in step 2 into the electroplating solution as the cathode and nickel as the anode. Connect the DC current at 50°C and 2A / dm 2 Under the conditions of 400 nm, a nickel layer is deposited on the preform to obtain a nickel-plated cermet (nickel-plated TiC-Ni cermet), wherein the electroplating solution comprises: a NiSO4 solution with a concentration of 280 g / L, a NiCl2 solution with a concentration of 50 g / L, an H3BO4 solution with a concentration of 35 g / L, and a CH3(CH2) solution with a concentration of 1 g / L. 11 OSO3Na solution, cerium oxide with a content of 10%, and distilled water are added to 200mL.

[0041] Step 4: Braze the two substrates to be welded: Clean 304 stainless steel, Ag-Cu brazing filler metal foil, and nickel-plated TiC-Ni cermet are stacked in order from bottom to top, secured, and then placed in a vacuum brazing furnace. The temperature is raised to 800°C at a heating rate of 15°C / min, held for 10 minutes, then cooled to 400°C at a cooling rate of 10°C / min. The furnace is then opened and the brazing of the nickel-plated TiC-Ni cermet to the 304 stainless steel is complete. The tensile shear strength tested using a universal tensile tester is 48 MPa.

[0042] Comparative Example 1

[0043] A method for connecting ceramic or ceramic-based composite materials and metal materials using an inactive brazing filler metal, the specific steps of which are as follows:

[0044] Step 1: Pre-treat the substrate to be welded: polish the base material (15mm×25mm×3mm 304 stainless steel and 5mm×5mm×3mm TiC-Ni metal ceramic) with sandpaper, and then clean it with acetone for 15 minutes to obtain clean TiC-Ni metal ceramic, 304 stainless steel and Ag-Cu foil solder to be welded;

[0045] Step 2: Pretreat the TiC-Ni metal ceramic to be welded: (roughening) Add 25mL of 40% hydrofluoric acid and dilute it with water to 100mL, then add the TiC-Ni metal ceramic to be welded and roughen it for 15min, and rinse with distilled water; (sensitization) Weigh 10g of stannous chloride and 92mL of hydrochloric acid, add the two chemicals to a beaker, dilute to 1L, add the roughened ceramic to the beaker, sensitize at room temperature for 30min, and rinse with distilled water 3 times after sensitization; (activation) Weigh 0.5g of palladium dichloride, 20g of boric acid, and 0.5mL of hydrochloric acid, place the above chemicals in a 1L beaker and dilute them to 1L, add the sensitized ceramic to the beaker, activate at room temperature for 30min, and rinse with distilled water 3 times.

[0046] Step 3: Prepare the coating: Immerse the TiC-Ni metal ceramic pretreated in step 2 into the electroplating solution as the cathode and nickel as the anode. Connect the DC current at 50°C and 2A / dm 2 Under the conditions of 400 nm, a nickel layer is deposited on the preform to obtain a nickel-plated cermet (nickel-plated TiC-Ni cermet), wherein the electroplating solution comprises: a NiSO4 solution with a concentration of 280 g / L, a NiCl2 solution with a concentration of 50 g / L, an H3BO4 solution with a concentration of 35 g / L, and a CH3(CH2) solution with a concentration of 1 g / L. 11OSO3Na solution, add distilled water to 200mL.

[0047] Step 4: Braze the two substrates to be welded: Clean 304 stainless steel, Ag-Cu brazing filler metal foil, and nickel-plated TiC-Ni cermet are stacked in order from bottom to top, secured, and then placed in a vacuum brazing furnace. The temperature is raised to 800°C at a heating rate of 15°C / min, held for 10 minutes, then cooled to 400°C at a cooling rate of 10°C / min. The furnace is then opened and the brazing of the nickel-plated TiC-Ni cermet to the 304 stainless steel is complete. The tensile shear strength tested using a universal tensile tester is 42 MPa.

[0048] Figure 1 The microstructure of the brazed joint between the Ni-plated cermet and 304 stainless steel obtained in Example 2. Figure 1 It can be observed that there are no defects such as pores and unwelded parts in the brazing seam. The interface between the ceramic and the base materials on both sides reacts fully, forming a good metallurgical bond. A continuous and better-performing banded solid solution is formed on the ceramic base material side. At the same time, the addition of rare earths refines the grains and reduces the dissolution of the coating by the brazing material, thereby improving the strength of the joint.

[0049] Although the present invention has been described in considerable detail and with particularity with respect to several described embodiments, it is not intended to be limited to any of these details or embodiments or any particular embodiment, but rather should be construed as providing a broad possible interpretation of these claims in view of the prior art by reference to the appended claims, thereby effectively encompassing the intended scope of the invention. In addition, the invention has been described above in terms of embodiments foreseen by the inventors for the purpose of providing a useful description, and those insubstantial modifications of the invention that are not currently foreseen may still represent equivalent modifications of the invention.

Claims

1. A method for connecting ceramic material and metal material using an inactive brazing filler metal, characterized in that: The following steps are involved: Step 1: Grind the ceramic material to be welded, the metal material to be welded, and the Ag-Cu foil solder with sandpaper, and then clean them with acetone for 10 to 20 minutes to obtain clean ceramic material to be welded, metal material to be welded, and Ag-Cu foil solder; Step 2: Immerse the ceramic material to be welded in the electroplating solution as the cathode and the nickel metal as the anode. After connecting the DC current, the current is 1-2A / dm at 50℃. 2 Electroplating for 10 minutes under the conditions of the present invention, a metal nickel layer is deposited on the prefabricated ceramic to obtain a nickel-plated metal ceramic; the electroplating solution includes: NiSO4 solution, NiCl2 solution, H3BO4 solution, CH3(CH2) 11 OSO3Na solution, cerium oxide and water; Step 3: stack the clean metal material to be welded, Ag-Cu foil solder and nickel-plated metal ceramic in order from bottom to top, and fix them to obtain the workpiece to be welded; place the workpiece to be welded in a vacuum brazing furnace, heat it to 790°C to 900°C at a heating rate of 1°C / min to 50°C / min, keep it warm for 5min to 30min, then cool it to 400°C at a cooling rate of 2°C / min to 20°C / min, and then cool it to 150°C with the furnace. Open the furnace and take out the workpiece, thus obtaining the brazing of the ceramic material and the metal material; The concentrations of the plating solution components in step 2 are as follows: The concentration of NiSO4 solution is 280g / L, the concentration of NiCl2 solution is 50g / L, the concentration of H3BO4 solution is 35g / L, and the concentration of CH3(CH2) 11 The concentration of OSO3Na solution is 1g / L, and the cerium oxide content is 1%-10%; The ceramic material to be welded is TiC-Ni metal ceramic; the metal material to be welded is 304 stainless steel.

2. The method according to claim 1, characterized in that Before step 2, a pretreatment step is also included, in which the clean ceramic material to be welded is roughened-cleaned-sensitized-cleaned-activated-cleaned.

3. The method according to claim 2, characterized in that The specific process of roughening-cleaning-sensitization-cleaning-activation-cleaning is as follows: First, place the clean ceramic material to be welded in 10% hydrofluoric acid for roughening for 15 minutes, and then wash with distilled water; then weigh 10g of stannous chloride, measure 92mL of hydrochloric acid, dilute to 1L with water, add the roughened ceramic material, sensitize at room temperature for 30 minutes, and wash with distilled water 2-3 times after sensitization; finally, weigh 0.5g of palladium dichloride, 20g of boric acid, measure 0.5mL of hydrochloric acid, dilute to 1L with water, add the sensitized ceramic, activate at room temperature for 30 minutes, and wash with distilled water 2-3 times.

4. The method according to claim 1, wherein The content of cerium oxide is 5%.

5. The method according to claim 1, wherein The acetone cleaning time in step 1 is 15 minutes.

6. The method according to claim 1, characterized in that The current in step 2 is 2A / dm.

7. The method according to claim 1, characterized in that In step 3, the heating rate is 15°C / min, and the temperature is raised to 900°C.

8. The method according to claim 1, characterized in that In step 3, the cooling rate is 10°C / min, and the temperature is reduced to 400°C.

9. The method according to claim 1, characterized in that The holding time in step 3 is 10 min.

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