Production method for manufacturing ultra-precision cubic boron nitride grinding tool through plasma arc fusion and electron beam finishing

Abstract

The invention discloses a production method for manufacturing an ultra-precise cubic boron nitride grinding tool through plasma arc fusion and electron beam finishing. The production method comprises the steps that metal alloy powder slurry is prepared; uniformly spraying the prepared metal alloy powder slurry on the surface of a steel substrate; cubic boron nitride micro-powder particles are uniformly sprayed and adhered to the surface of the metal alloy powder slurry; heating the metal alloy powder slurry by using plasma arc in a vacuum protection atmosphere until the alloy powder is molten; and performing electron beam finishing to remove salient points, floating sand and alloy bumps on the surface of the grinding tool. The grinding tool manufactured by the production method has the advantages of high grinding efficiency, long service life, high grinding precision and the like; the production method can be used for manufacturing a special ultra-precision grinding tool with a slender substrate, a thin wall and fine cubic boron nitride; the plasma arc energy density is high, the heating and cooling speed is high, the thermal damage of cubic boron nitride is small, and a grinding tool base body almost has no thermal deformation; protruding points on the surface of the grinding tool can be removed through electron beam finishing, and the surface is smooth, free of floating sand and free of alloy tumors.

Description

Technical Field

[0001] The invention belongs to the field of cubic boron nitride grinding tool manufacturing, in particular to a production method for manufacturing ultra-precision cubic boron nitride grinding tools by plasma arc fusion and electron beam finishing. Background Art

[0002] Metal materials such as titanium alloys, nickel-based high-temperature alloys, and high-strength stainless steel have the advantages of high strength, high toughness, and high temperature resistance. They have become important materials in the aviation, aerospace, military, and automotive industries.

[0003] Cubic boron nitride abrasives are used to process these high-strength materials. Cubic boron nitride abrasives can be divided into electroplated abrasives, sintered abrasives, and brazed abrasives according to different manufacturing processes. The bonding strength between cubic boron nitride and the binder of abrasives made by electroplating and sintering processes is low, and the cubic boron nitride is easy to fall off. Abrasives made by brazing process are achieved by resistance heating in a vacuum furnace. The cubic boron nitride is firmly bonded to the binder, but due to the slow heating speed, the cubic boron nitride is subjected to high temperature for a long time, and the thermal damage is serious. The strength of the cubic boron nitride is reduced and it is easy to break. Moreover, only coarse-grained cubic boron nitride can be brazed, and fine-grained cubic boron nitride cannot be brazed. Therefore, the current process cannot produce high-bonding-strength fine-grained cubic boron nitride precision abrasives. Summary of the invention

[0004] The purpose of the invention is to provide a production method for manufacturing ultra-precision cubic boron nitride grinding tools by plasma arc fusion and electron beam dressing, which can manufacture high-bonding strength fine-grained cubic boron nitride precision grinding tools.

[0005] Technical solution: The production method of the ultra-precision cubic boron nitride grinding tool by plasma arc fusion and electron beam finishing of the present invention comprises the following steps:

[0006] Step 1, preparing a metal alloy powder slurry;

[0007] Step 2, spraying the prepared metal alloy powder slurry evenly on the surface of the steel substrate;

[0008] Step 3, spraying cubic boron nitride powder particles evenly onto the surface of the metal alloy powder slurry;

[0009] Step 4, using a plasma arc to heat the metal alloy powder slurry in a vacuum protective atmosphere until the alloy powder is melted, and after cooling, the cubic boron nitride powder particles and the alloy are fused and fixed on the surface of the steel substrate to form a grinding tool;

[0010] Step 5: Electron beam finishing to remove convex spots, floating sand and alloy nodules on the surface of the mold.

[0011] Furthermore, in step 1, when preparing the metal alloy powder slurry, the alloy powder and glue are evenly mixed in a mass ratio of 1:1-2 to form the metal alloy powder slurry.

[0012] Furthermore, the alloy powder is Cu-Co-Cr-Ti-Fe alloy powder, Ag-Cu-Sn-In-Ti alloy powder and Cu-Ni-Sn-Ti alloy powder.

[0013] Furthermore, the glue comprises the following components by mass percentage: 20-25% polyvinyl alcohol, 15-20% ammonium acryloyl, 5-8% sodium hydroxide, 3-5% ethanol, and the balance is water.

[0014] Furthermore, in step 2, after spraying is completed, the thickness of the metal alloy powder slurry sprayed on the surface of the steel substrate after solidification is 130-150% of the average particle size of the cubic boron nitride micropowder particles.

[0015] Furthermore, in step 3, after spraying and adhering, the average gap between two adjacent cubic boron nitride micropowder particles is 2 to 3 times the average particle size of the cubic boron nitride micropowder particles.

[0016] Furthermore, in step 3, the particle size range of the cubic boron nitride powder particles is 100 to 10000 mesh.

[0017] Furthermore, when the metal alloy powder slurry is heated by a plasma arc, the fusion temperature is the melting point of the alloy powder + 60 to 100°C.

[0018] Compared with the prior art, the present invention has the following beneficial effects: the abrasive tool produced by the production method of the present invention has the advantages of high grinding efficiency, long service life, high grinding precision, etc.; the production method can produce special ultra-precision abrasive tools with a slender matrix, thin wall, and fine cubic boron nitride; the plasma arc has high energy density, fast heating and cooling speed, small thermal damage to cubic boron nitride, and almost no thermal deformation of the abrasive tool matrix; electron beam finishing can be used to remove convex points on the surface of the abrasive tool, and the surface is smooth, without floating sand and alloy nodules. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The figure is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0020] The technical solution of the present invention is described in detail below with reference to the accompanying drawings, but the protection scope of the present invention is not limited to the embodiments.

[0021] like Figure 1 As shown, the production method of the ultra-precision cubic boron nitride grinding tool by plasma arc fusion and electron beam finishing disclosed in the present invention comprises the following steps:

[0022] Step 1, preparing a metal alloy powder slurry, specifically, mixing the alloy powder and glue in a mass ratio of 1:1-2 to form a metal alloy powder slurry, wherein the alloy powder is Cu-Co-Cr-Ti-Fe alloy powder, Ag-Cu-Sn-In-Ti alloy powder and Cu-Ni-Sn-Ti alloy powder, and the glue comprises the following components by mass percentage: 20-25% polyvinyl alcohol, 15-20% ammonium acryloyl, 5-8% sodium hydroxide, 3-5% ethanol, and the balance is water;

[0023] Step 2, spraying the prepared metal alloy powder slurry evenly on the surface of the steel substrate, after the spraying is completed, the thickness of the metal alloy powder slurry sprayed on the surface of the steel substrate after solidification is 130-150% of the average particle size of the cubic boron nitride micropowder particles;

[0024] Step 3, spraying cubic boron nitride micropowder particles uniformly onto the surface of the metal alloy powder slurry, wherein after spraying and adhering, the average gap between two adjacent cubic boron nitride micropowder particles is 2 to 3 times the average particle size of the cubic boron nitride micropowder particles, and the particle size range of the cubic boron nitride micropowder particles is 100 to 10000 mesh;

[0025] Step 4, in a vacuum protective atmosphere, the metal alloy powder slurry is heated by a plasma arc until the alloy powder is melted, the fusion temperature is the melting point of the alloy powder + 60 to 100° C., and after cooling, the cubic boron nitride powder particles are fused with the alloy and fixed on the surface of the steel substrate to form a grinding tool;

[0026] Step 5: Electron beam finishing to remove convex spots, floating sand and alloy nodules on the surface of the mold.

[0027] In order to verify the performance of the abrasive tool produced by the production method of the present invention, the present invention provides the following four embodiments:

[0028] Embodiment 1:

[0029] The production method of ultra-precision cubic boron nitride abrasive tools by plasma arc fusion and electron beam finishing is as follows:

[0030] Step 1, mixing alloy powder and glue in a mass ratio of 1:2 to form a metal alloy powder slurry, wherein the alloy powder is Cu-Co-Cr-Ti-Fe alloy powder, and the glue comprises the following components by mass percentage: 25% polyvinyl alcohol, 20% ammonium acryloyl, 8% sodium hydroxide, 5% ethanol, and the balance is water;

[0031] Step 2, spraying the metal alloy powder slurry evenly on the surface of the steel substrate, the thickness of the metal alloy powder slurry after solidification is 140-150% of the average particle size of the cubic boron nitride micropowder particles, and the particle size of the cubic boron nitride micropowder particles is 500 mesh;

[0032] Step 3, spraying cubic boron nitride powder particles uniformly onto the surface of the metal alloy powder slurry, wherein the average gap between two adjacent cubic boron nitride particles is 2.5 to 3 times the average particle size of the cubic boron nitride;

[0033] Step 4, heating the alloy powder with a plasma arc in a vacuum protective atmosphere until the alloy powder is melted, the fusion temperature is the melting point of the alloy powder + 100°C, and after cooling, the cubic boron nitride particles and the alloy are fused and fixed on the surface of the substrate to form a grinding tool;

[0034] Step 5: Electron beam finishing is used to remove convex spots, floating sand and alloy nodules on the surface of the mold to make the surface of the mold smooth.

[0035] Embodiment 2:

[0036] The production method of ultra-precision cubic boron nitride abrasive tools by plasma arc fusion and electron beam finishing is as follows:

[0037] Step 1, mixing alloy powder and glue in a mass ratio of 1:1 to form a metal alloy powder slurry, wherein the alloy powder is Cu-Co-Cr-Ti-Fe alloy powder, and the glue comprises the following components by mass percentage: 23% polyvinyl alcohol, 18% ammonium acryloyl, 7% sodium hydroxide, 4.5% ethanol, and the balance is water;

[0038] Step 2, spraying the metal alloy powder slurry evenly on the surface of the steel substrate, the thickness of the metal alloy powder slurry after solidification is 135-145% of the average particle size of the cubic boron nitride micropowder particles, and the particle size of the cubic boron nitride micropowder particles is 2000 mesh;

[0039] Step 3, spraying cubic boron nitride micropowder particles uniformly onto the surface of the metal alloy powder slurry, wherein the average gap between two adjacent cubic boron nitride micropowder particles is 2.2 to 2.5 times the average particle size of the cubic boron nitride micropowder particles;

[0040] Step 4, heating the alloy powder with a plasma arc in a vacuum protective atmosphere until the alloy powder is melted, the fusion temperature is the melting point of the alloy powder + 60°C, and after cooling, the cubic boron nitride powder particles and the alloy are fused and fixed on the surface of the substrate to form a grinding tool;

[0041] Step 5: Electron beam finishing is used to remove convex spots, floating sand and alloy nodules on the surface of the mold to ensure a smooth surface of the mold.

[0042] Embodiment 3:

[0043] The production method of ultra-precision cubic boron nitride abrasive tools by plasma arc fusion and electron beam finishing is as follows:

[0044] Step 1, mixing alloy powder and glue in a mass ratio of 1:1 to form a metal alloy powder slurry, wherein the alloy powder is Ag-Cu-Sn-In-Ti alloy powder, and the glue comprises the following components by mass percentage: 22% polyvinyl alcohol, 17% ammonium acryloyl, 6% sodium hydroxide, 4% ethanol, and the balance is water;

[0045] Step 2, spraying the metal alloy powder slurry evenly on the surface of the steel substrate, the thickness of the metal alloy powder slurry after solidification is 130-140% of the average particle size of the cubic boron nitride micropowder particles, and the particle size of the cubic boron nitride micropowder particles is 5000 mesh;

[0046] Step 3, spraying cubic boron nitride powder particles uniformly onto the surface of the metal alloy powder slurry, wherein the average gap between two adjacent cubic boron nitride powder particles is 2 to 2.3 times the average particle size of the cubic boron nitride powder particles;

[0047] Step 4, heating the alloy powder with a plasma arc in a vacuum protective atmosphere until the alloy powder is melted, the fusion temperature is the melting point of the alloy powder + 60°C, and after cooling, the cubic boron nitride powder particles and the alloy are fused and fixed on the surface of the substrate to form a grinding tool;

[0048] Step 5: Electron beam finishing is used to remove convex spots, floating sand and alloy nodules on the surface of the mold to ensure a smooth surface of the mold.

[0049] Embodiment 4:

[0050] The production method of ultra-precision cubic boron nitride abrasive tools by plasma arc fusion and electron beam finishing is as follows:

[0051] Step 1, mixing alloy powder and glue in a mass ratio of 1:1 to form a metal alloy powder slurry, wherein the alloy powder is Cu-Ni-Sn-Ti alloy powder, and the glue comprises the following components by mass percentage: 20% polyvinyl alcohol, 15% ammonium acryloyl, 5% sodium hydroxide, 3% ethanol, and the balance is water;

[0052] Step 2, spraying the metal alloy powder slurry evenly on the surface of the steel substrate, the thickness of the metal alloy powder slurry after solidification is 130-135% of the average particle size of cubic boron nitride, and the particle size of the cubic boron nitride micropowder particles is 10000 mesh;

[0053] Step 3, spraying cubic boron nitride micropowder particles uniformly onto the surface of the metal alloy powder slurry, wherein the average gap between two adjacent cubic boron nitride micropowder particles is 2 to 2.2 times the average particle size of the cubic boron nitride micropowder particles;

[0054] Step 4, heating the alloy powder with a plasma arc in a vacuum protective atmosphere until the alloy powder is melted, the fusion temperature is the melting point of the alloy powder + 60°C, and after cooling, the cubic boron nitride powder particles and the alloy are fused and fixed on the surface of the substrate to form a grinding tool;

[0055] Step 5: Electron beam finishing is used to remove convex spots, floating sand and alloy nodules on the surface of the mold to ensure a smooth surface of the mold.

[0056] Among the above 4 embodiments, it can be seen through experimental comparison that embodiment 4 is the best embodiment and the disclosed parameters are the best parameter settings.

[0057] As described above, although the present invention has been shown and described with reference to specific preferred embodiments, it should not be construed as limiting the present invention itself. Various changes in form and details may be made without departing from the spirit and scope of the present invention as defined in the appended claims.

Claims

1. A method for producing ultra-precision cubic boron nitride abrasive tools by plasma arc fusion and electron beam finishing, characterized in that: The steps include: Step 1, preparing a metal alloy powder slurry; Step 2, spraying the prepared metal alloy powder slurry evenly on the surface of the steel substrate; Step 3, spraying cubic boron nitride powder particles evenly onto the surface of the metal alloy powder slurry; Step 4, using a plasma arc to heat the metal alloy powder slurry in a vacuum protective atmosphere until the alloy powder is melted, and after cooling, the cubic boron nitride powder particles are fused with the alloy and fixed on the surface of the steel substrate to form a grinding tool; Step 5: Electron beam finishing to remove convex spots, floating sand and alloy nodules on the surface of the mold.

2. The method for producing ultra-precision cubic boron nitride abrasive tools by plasma arc fusion and electron beam finishing according to claim 1, characterized in that: In step 1, when preparing the metal alloy powder slurry, the alloy powder and glue are evenly mixed in a mass ratio of 1:1-2 to form the metal alloy powder slurry.

3. The method for producing ultra-precision cubic boron nitride abrasive tools by plasma arc fusion and electron beam finishing according to claim 2, characterized in that: The alloy powders are Cu-Co-Cr-Ti-Fe alloy powders, Ag-Cu-Sn-In-Ti alloy powders, and Cu-Ni-Sn-Ti alloy powders.

4. The method for producing ultra-precision cubic boron nitride abrasive tools by plasma arc fusion and electron beam finishing according to claim 2, characterized in that: The components of the glue in percentage by mass are: 20-25% of polyvinyl alcohol, 15-20% of ammonium acryloyl, 5-8% of sodium hydroxide, 3-5% of ethanol, and the balance is water.

5. The method for producing ultra-precision cubic boron nitride abrasive tools by plasma arc fusion and electron beam finishing according to claim 1, characterized in that: In step 2, after spraying is completed, the thickness of the metal alloy powder slurry sprayed on the surface of the steel substrate after solidification is 130-150% of the average particle size of the cubic boron nitride micropowder particles.

6. The method for producing ultra-precision cubic boron nitride abrasive tools by plasma arc fusion and electron beam finishing according to claim 1, characterized in that: In step 3, after spraying and adhering, the average gap between two adjacent cubic boron nitride micropowder particles is 2 to 3 times the average particle size of the cubic boron nitride micropowder particles.

7. The method for producing ultra-precision cubic boron nitride abrasive tools by plasma arc fusion and electron beam finishing according to claim 1, characterized in that: In step 3, the particle size range of the cubic boron nitride powder particles is 100 to 10000 mesh.

8. The method for producing ultra-precision cubic boron nitride abrasive tools by plasma arc fusion and electron beam finishing according to claim 1, characterized in that: When the metal alloy powder slurry is heated by a plasma arc, the fusion temperature is the melting point of the alloy powder + 60 to 100°C.

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