Low-melting-point repair brazing filler metal for repair welding of high-temperature nickel-based alloy honeycomb and preparation method of low-melting-point repair brazing filler metal

Abstract

The invention relates to low-melting-point repair brazing filler metal for repair welding of a high-temperature nickel-based alloy honeycomb and a preparation method of the low-melting-point repair brazing filler metal. The repair brazing filler metal comprises the following chemical components in percentage by mass: 10-20% of Au, 5.6-7.2% of Cr, 2.5-3.15% of B, 3.6-4.5% of Si, 1.0-1.5% of Ge and the balance of Ni. The preparation method comprises the following steps: preparing the repair brazing filler metal into an amorphous sheet, powder or soldering paste; the using method comprises the following steps: cleaning a damaged part, manufacturing a repairing part, and carrying out brazing repair welding by using the repairing brazing filler metal. According to the technical scheme, honeycomb brazing defects and faults are completely repaired, the state of the repaired position is stable, the strength is good, the technical requirements are met, and the qualification rate of honeycomb brazing repair welding is high. By adopting the repairing brazing filler metal and the technology for repairing honeycomb repair welding, compared with replacement of a new product, the repairing cost of a single piece is saved.

Description

Technical Field

[0001] The invention relates to the technical field of metal brazing, and in particular to a low-melting-point repair brazing filler metal for high-temperature nickel-based alloy honeycomb repair welding and a preparation method thereof. Background Art

[0002] As the most typical lightweight structure, it is widely used in the sealing structure of aircraft engines. The honeycomb structure has excellent spatial geometric dimensions and excellent mechanical properties. Compared with other structures of the same material, it has high specific strength, high specific stiffness, high toughness and good impact performance, as well as special properties of sound absorption and energy storage, heat dissipation and shock absorption, and electromagnetic shielding. In addition, the honeycomb structure is easy to process, which makes it very suitable for parts with complex shapes.

[0003] The sealing structure of aircraft engines is often made by vacuum brazing of high-temperature alloy honeycombs and high-temperature alloy plates. During the brazing process, local honeycomb damage and welding defects are prone to occur. At present, the defective position is repaired by remelting the original brazing material after sprinkling powder. This repair method not only reduces the strength of the original honeycomb material, but may also cause the original brazing seam to remelt. Therefore, it is very important to find a new low-melting point repair brazing material and repair method. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a low melting point repair brazing filler metal for high temperature nickel-based alloy honeycomb repair welding and a preparation method thereof; the specific technical scheme is as follows:

[0005] A low melting point solder for repairing high temperature nickel-based alloy honeycomb, the chemical components of the low melting point solder are as follows: Au: 10-20%, Cr: 5.6-7.2%, B: 2.5-3.15%, Si: 3.6-4.5%, Ge: 1.0-1.5%, and the balance is Ni.

[0006] A low melting point brazing material for repairing high temperature nickel-based alloy honeycombs, wherein the preferred embodiment is to mix low melting point nickel-based alloy powder and a binder evenly to prepare a solder paste;

[0007] The binder is used to improve the fluidity of the solder, facilitate coating on the workpiece, and is also used to remove oxides on the surface of the base material and the solder.

[0008] The method for preparing a low-melting-point solder for repairing a high-temperature nickel-based alloy honeycomb, in a preferred embodiment, comprises the following steps:

[0009] Step 1: Weigh each raw material according to the mass percentage, ultrasonically clean the raw materials in an acetone solution for 15 minutes, then ultrasonically clean them in an alcohol solution for 5 minutes, and dry them for later use;

[0010] Step 2: Evenly mix the nickel raw material, chromium raw material, gold raw material, silicon raw material, boron raw material and germanium raw material, place them in a vacuum arc melting furnace, evacuate low vacuum and then fill with argon, and repeatedly melt for 4 times to obtain a nickel-based alloy ingot, and take it out from the vacuum arc melting furnace after cooling, and grind to remove the metal scum on the surface to obtain the gold-containing low-melting-point repair brazing material.

[0011] The preferred embodiment of the method for preparing a low melting point solder for repairing a high temperature nickel-based alloy honeycomb is that in step 1, the concentration of the acetone solution is 99.5%.

[0012] The method for preparing a low-melting-point brazing filler metal for repairing a high-temperature nickel-based alloy honeycomb has a preferred embodiment in which, in step 2, the vacuum degree of the low vacuum is 1×10-1Pa, the repeated smelting is performed at an interval of 5 minutes each time, the smelting temperature is 1200°C-1300°C, and the smelting time is 10-30 minutes, so as to facilitate the full diffusion and fusion of the elements.

[0013] The method for preparing a low melting point solder for repairing a high temperature nickel-based alloy honeycomb, the preferred embodiment of which is a method for using the low melting point gold-containing solder, comprising the following steps:

[0014] Step 1: Use a cutting machine to clean the area to be repaired and process the corresponding repair patch. The size of the patch should be larger than the size of the area to be repaired, but not too large. L is 0.3-0.5 times the honeycomb radius.

[0015] Step 2: Clean, polish, and pickle the repaired area and patch to remove oil and oxide film on the surface of the material;

[0016] Step 3: Install the patch on the area to be repaired, carefully adjust the position, and apply solder paste or put solder foil into the gap between the patch and the original honeycomb;

[0017] Step 4: Place the assembled honeycomb and brazing material in a high-temperature brazing furnace for welding. The welding parameters are 980°C / 60min and the vacuum degree is 3×10-3Pa.

[0018] Step 5: After brazing, clean the brazing seam to remove residual brazing material and flux.

[0019] Compared with the prior art, the present invention has the following beneficial technical effects:

[0020] The technical solution adopted by the present invention can ensure that the gold-containing low-melting-point repair solder has a stable composition ratio and does not contain excessive impurities. The binder can improve the fluidity of the solder, making it easier to apply to the workpiece, and can also remove oxides on the surface of the base material and the solder, thereby improving the welding quality.

[0021] The present invention is conducive to the preparation of a low-melting-point gold-containing repair brazing material that can be used to repair nickel-based high-temperature alloy honeycombs. Compared with the traditional high-melting-point brazing material powder repair method, the present method simultaneously ensures the strength of the repaired honeycomb mother material and the original weld.

[0022] The method of use of the present invention is applied in the honeycomb repair of the sealing structure of an aircraft engine, and the honeycomb brazing defect fault is completely repaired. The repair position state is stable, the strength is good, and the technical requirements are met, thereby improving the qualified rate of the honeycomb brazing repair. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The tensile curve of the high temperature nickel-based alloy of the embodiment;

[0024] Figure 2 A schematic diagram of cleaning a damaged area and making a patch in an embodiment;

[0025] Figure 3 It is a schematic diagram of the assembly patch and filling solder of the embodiment. DETAILED DESCRIPTION

[0026] The following is combined with Figure 1-3 The present invention is described in detail, but the protection scope of the present invention is not limited by the accompanying drawings.

[0027] Example 1

[0028] A method for preparing a low melting point brazing material for repairing a high temperature nickel-based alloy honeycomb comprises the following steps:

[0029] Step 1: Prepare solder, Au: 10%, Cr: 6%, B: 2.5%, Si: 4%, Ge: 1%, and the balance is Ni. Weigh various high-purity raw materials according to the above mass percentages, and the purity of various high-purity raw materials is not less than 99.99%;

[0030] Step 2: Weigh each raw material according to the mass percentage, ultrasonically clean the raw materials in an acetone solution for 15 minutes, then ultrasonically clean them in an alcohol solution for 5 minutes, and dry them for later use; wherein the concentration of the acetone solution is 99.5%;

[0031] Step 3: Evenly mix the nickel raw material, chromium raw material, gold raw material, silicon raw material, boron raw material and germanium raw material, place them in a vacuum arc melting furnace, evacuate low vacuum and fill with argon, and repeatedly melt four times to obtain a nickel-based alloy ingot, take it out from the vacuum arc melting furnace after cooling, and polish to remove the metal scum on the surface to obtain the gold-containing low-melting-point repair solder; the vacuum degree of the low vacuum is 1×10-1Pa, the repeated melting is 5min each time, the melting temperature is 1200℃-1300℃, and the melting time is 10min-30min, so as to facilitate the full diffusion and fusion of each element.

[0032] Step 4: The bulk alloy is made into an amorphous sheet. The preparation method of the amorphous sheet is a single-roller rapid cooling method. The thickness of the amorphous sheet is 50 μm.

[0033] Step 5: Assemble the nickel-based alloy plate and the brazing material and place them in a high-temperature brazing furnace for welding. The welding parameters are 980°C / 60min and the vacuum degree is 3×10-3Pa.

[0034] Step 6: After welding is completed, the sample is subjected to a tensile test. The tensile strength can reach about 600MPa, indicating that the welding quality is good.

[0035] Example 2

[0036] A method for preparing a low melting point brazing material for repairing a high temperature nickel-based alloy honeycomb comprises the following steps:

[0037] Step 1: Prepare solder, the composition is Au: 20%, Cr: 7%, B: 3%, Si: 4.5%, Ge: 1.5%, and the balance is Ni. Weigh various high-purity raw materials according to the above mass percentages, and the purity of various high-purity raw materials is not less than 99.99%;

[0038] Step 2: Weigh each raw material according to the mass percentage, ultrasonically clean the raw materials in an acetone solution for 15 minutes, then ultrasonically clean them in an alcohol solution for 5 minutes, and dry them for later use; the concentration of the acetone solution is 99.5%;

[0039] Step 3: uniformly mixing nickel raw material, chromium raw material, gold raw material, silicon raw material, boron raw material and germanium raw material, placing the raw material in a vacuum arc melting furnace, evacuating low vacuum and then filling with argon gas, and repeatedly melting four times to obtain a nickel-based alloy ingot, and taking it out from the vacuum arc melting furnace after cooling, grinding and removing the metal scum on the surface, and obtaining the gold-containing low-melting-point repair brazing material;

[0040] The vacuum degree of the low vacuum is 1×10-1Pa, the interval between each repeated smelting is 5 minutes, the smelting temperature is 1200°C-1300°C, and the smelting time is 10 minutes-30 minutes, so that each element can be fully diffused and fused;

[0041] Step 4: The bulk alloy is made into an amorphous sheet. The preparation method of the amorphous sheet is a single-roller rapid cooling method. The thickness of the amorphous sheet is 50 μm.

[0042] Step 5: Make welding test blocks: The size of the nickel-based alloy honeycomb test block is 100x100 mm, the size of the area to be repaired is 50x50mm, and the honeycomb size is 12.8mm; the size of the patch block is 55x55mm, and the honeycomb size is consistent with the material to be repaired;

[0043] Step 6: Assemble the patch block and the honeycomb to be repaired, adjust the position and put the solder foil into the gap between the two test blocks;

[0044] Step 7: The honeycomb and the brazing material are placed in a high-temperature brazing furnace for welding. The welding parameters are 980°C / 60min and the vacuum degree is 3×10-3Pa.

[0045] Step 8: After welding is completed, the weld quality is tested. No cracks are found in any weld and the welding quality is good.

Claims

1. A low melting point brazing material for repairing high temperature nickel-based alloy honeycombs, characterized in that: The mass percentages of the chemical components of the low melting point solder are: Au: 10-20%, Cr: 5.6-7.2%, B: 2.5-3.15%, Si: 3.6-4.5%, Ge: 1.0-1.5%, and the balance is Ni.

2. The low melting point brazing filler metal for repairing high temperature nickel-based alloy honeycomb according to claim 1, characterized in that: The low melting point nickel-based alloy powder and the binder are uniformly mixed to prepare solder paste; The binder is used to improve the fluidity of the solder, facilitate coating on the workpiece, and is also used to remove oxides on the surface of the base material and the solder.

3. The method for preparing a low melting point brazing filler metal for repairing a high temperature nickel-based alloy honeycomb according to claim 1, characterized in that: The preparation method of the low melting point solder comprises the following steps: Step 1: Weigh each raw material according to the mass percentage, ultrasonically clean the raw materials in an acetone solution for 15 minutes, then ultrasonically clean them in an alcohol solution for 5 minutes, and dry them for later use; Step 2: Evenly mix the nickel raw material, chromium raw material, gold raw material, silicon raw material, boron raw material and germanium raw material, place them in a vacuum arc melting furnace, evacuate low vacuum and then fill with argon, and repeatedly melt for 4 times to obtain a nickel-based alloy ingot, and take it out from the vacuum arc melting furnace after cooling, and grind to remove the metal scum on the surface to obtain the gold-containing low-melting-point repair brazing material.

4. The method for preparing a low melting point brazing filler metal for repairing a high temperature nickel-based alloy honeycomb according to claim 3, characterized in that: In step 1, the concentration of the acetone solution is 99.5%.

5. The method for preparing a low melting point brazing filler metal for repairing a high temperature nickel-based alloy honeycomb according to claim 3, characterized in that: In step 2, the vacuum degree of the low vacuum is 1×10-1Pa, the repeated smelting is performed with an interval of 5 minutes each time, the smelting temperature is 1200°C-1300°C, and the smelting time is 10-30 minutes, so that each element can be fully diffused and fused.

6. The method for preparing a low melting point brazing filler metal for repairing a high temperature nickel-based alloy honeycomb according to claim 4, characterized in that: The method for using the low melting point gold-containing solder comprises the following steps: Step 1: Use a cutting machine to clean the area to be repaired and process the corresponding repair patch. The size of the patch should be larger than the size of the area to be repaired, but not too large. L is 0.3-0.5 times the honeycomb radius. Step 2: Clean, polish, and pickle the repaired area and patch to remove oil and oxide film on the surface of the material; Step 3: Install the patch on the area to be repaired, carefully adjust the position, and apply solder paste or put solder foil into the gap between the patch and the original honeycomb; Step 4: Place the assembled honeycomb and brazing material in a high-temperature brazing furnace for welding. The welding parameters are 980°C / 60min and the vacuum degree is 3×10-3Pa. Step 5: After brazing, clean the brazing seam to remove residual brazing material and flux.

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