阅读说明：本技术 一种切削难加工材料的金属陶瓷复合刀具的制备方法 (Preparation method of metal ceramic composite cutter for cutting difficult-to-machine materials ) 是由 丁海军 于 2020-06-15 设计创作，主要内容包括：本发明公开了一种切削难加工材料的金属陶瓷复合刀具的制备方法,依次包括如下步骤：S1制备表层混合粉；S2制备基体混合粉；S3配比填料；S4真空热压烧结；S5研磨和抛光。本发明制备的刀具材料表层硬度高、耐磨性好、断裂韧度高、抗弯强度高且抗断裂能力好,制造出的刀具综合力学性能满足高速切削刀具的使用要求。(The invention discloses a preparation method of a metal ceramic composite cutter for cutting difficult-to-machine materials, which sequentially comprises the following steps: s1, preparing surface layer mixed powder; s2 preparing matrix mixed powder; s3, proportioning fillers; s4, vacuum hot-pressing sintering; s5 grinding and polishing. The cutter material prepared by the invention has high surface hardness, good wear resistance, high fracture toughness, high bending strength and good fracture resistance, and the comprehensive mechanical properties of the manufactured cutter meet the use requirements of a high-speed cutting cutter.)

1. A preparation method of a metal ceramic composite cutter for cutting difficult-to-machine materials is characterized by sequentially comprising the following steps:

s1 reaction of TiB₂mixing-TiC composite material, vanadium carbide, molybdenum and nickel according to the mass ratio of 90-95: 1-5: 2-4Adding absolute ethyl alcohol, ball-milling, fully mixing uniformly, vacuum drying, and sieving with a 100-mesh sieve to obtain surface layer mixed powder;

s2, mixing Ti (C, N) cermet, molybdenum, nickel and cobalt according to the mass ratio of 85-90: 3-5: 4-6, adding absolute ethyl alcohol, ball milling, fully mixing uniformly, drying in vacuum and sieving with a 100-mesh sieve to obtain matrix mixed powder;

s3, sequentially placing the surface layer mixed powder, the matrix mixed powder and the surface layer mixed powder into a grinding tool according to the mass ratio of 1: 10-14: 1, flattening by using a material rod when each layer is placed, ensuring the thickness of each layer to be uniform, and sealing by using graphite blocks after the materials are loaded;

s4, carrying out vacuum hot-pressing sintering at a heating rate of 20-40 ℃/min, a sintering temperature of 1450-1500 ℃, a heat preservation time of 30-40min and a hot pressure of 30-40 Mpa;

s5 cutting the sintered product into needed size, grinding and polishing the surface with surface roughness Ra less than 0.1 μm.

2. The method of claim 1, wherein the TiB is a metal-ceramic composite tool for cutting difficult-to-machine materials₂TiB in-TiC composite material₂The mass ratio of TiC to TiC is 6-8: 2 to 4.

3. The method for manufacturing a cermet composite cutter for cutting difficult-to-machine materials as claimed in claim 1, wherein Ti (C, N) is a solid solution composed of TiC and TiN, wherein the mass ratio of TiC to TiN is 6-8: 2 to 4.

4. The method of claim 1, wherein the vanadium carbide has a particle size of 120nm or less.

Technical Field

The invention relates to the technical field of cutting tools, in particular to a preparation method of a metal ceramic composite tool for cutting difficult-to-machine materials.

Background

Cutting machining is one of the most widely used machining methods for machining, and in the metal cutting machining process, a front cutter face and a rear cutter face of a cutter are continuously contacted with chips and a workpiece, severe friction is generated, great cutting pressure and frictional heat are generated, and therefore a contact area is in a high-temperature and high-pressure state. Meanwhile, severe friction can cause tool wear to accelerate tool failure, making cutting impossible. Therefore, the tool material should have high hardness, high strength, good wear resistance and heat resistance.

With the continuous development of new material science, the performance of engineering materials is more and more excellent. In order to meet the processing requirements of new materials, the traditional cutting processing gradually changes and develops towards the directions of high speed, high efficiency and high precision, which puts higher requirements on the service performance of the cutter material. However, the hardness and the toughness of the existing homogeneous cutter material are difficult to be simultaneously improved, and the coated cutter has the problems of thin coating, weak interlayer interface binding force and the like. Therefore, research and development of the metal ceramic composite cutting tool capable of cutting difficult-to-machine materials at high speed and high efficiency become hot spots of research in the future and have wide application prospects.

Disclosure of Invention

The invention aims to provide a preparation method of a metal ceramic composite cutter for cutting difficult-to-machine materials, the surface layer of the cutter material has high hardness, good wear resistance, high fracture toughness, high bending strength and good fracture resistance, and the comprehensive mechanical properties of the manufactured cutter meet the use requirements of a high-speed cutting cutter.

In order to achieve the purpose, the invention provides the following technical scheme:

the embodiment of the application discloses a preparation method of a metal ceramic composite cutter for cutting difficult-to-machine materials, which sequentially comprises the following steps:

s1 reaction of TiB₂Mixing the-TiC composite material, the vanadium carbide, the molybdenum and the nickel according to the mass ratio of 90-95: 1-5: 2-4, adding absolute ethyl alcohol, ball milling, fully mixing uniformly, and then carrying out vacuum drying and sieving with a 100-mesh sieve to obtain surface layer mixed powder;

s2, mixing Ti (C, N) cermet, molybdenum, nickel and cobalt according to the mass ratio of 85-90: 3-5: 4-6, adding absolute ethyl alcohol, ball milling, fully mixing uniformly, drying in vacuum and sieving with a 100-mesh sieve to obtain matrix mixed powder;

s3, sequentially placing the surface layer mixed powder, the matrix mixed powder and the surface layer mixed powder into a grinding tool according to the mass ratio of 1: 10-14: 1, flattening by using a material rod when each layer is placed, ensuring the thickness of each layer to be uniform, and sealing by using graphite blocks after the materials are loaded;

s4, carrying out vacuum hot-pressing sintering at a heating rate of 20-40 ℃/min, a sintering temperature of 1450-1500 ℃, a heat preservation time of 30-40min and a hot pressure of 30-40 Mpa;

s5 cutting the sintered product into needed size, grinding and polishing the surface with surface roughness Ra less than 0.1 μm.

Preferably, TiB₂TiB in-TiC composite material₂The mass ratio of TiC to TiC is 6-8: 2 to 4.

Preferably, Ti (C, N) is a solid solution consisting of TiC and TiN, wherein the mass ratio of TiC to TiN is 6-8: 2 to 4.

The surface layer is added with a small amount of vanadium carbide, so that the density of the surface layer can be improved, the sintering temperature of the surface layer is reduced, and the matching degree of the surface layer and a matrix is increased, thereby improving the mechanical property of the whole material.

Preferably, the particle size of the vanadium carbide is less than or equal to 120 nm.

The invention has the advantages that:

1. the cutter material disclosed by the invention has the advantages of high surface hardness, good wear resistance, high fracture toughness, high bending strength and good fracture resistance, and the comprehensive mechanical properties of the manufactured cutter meet the use requirements of a high-speed cutting cutter.

2. The invention can directly obtain the high-performance cutting tool with hard surface layer and strong matrix without coating, the preparation method is simple, and the production cost is greatly reduced.

Detailed Description

Technical solutions in the embodiments of the present invention will be described in detail below, and it is apparent that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

Example 1

S1 reaction of TiB₂-TiC composite (TiB)₂The mass ratio of TiC to TiC is 7: 3) mixing vanadium carbide, molybdenum and nickel according to the mass ratio of 91: 4: 2: 3, adding absolute ethyl alcohol, ball-milling, fully mixing uniformly, vacuum drying and sieving by a 100-mesh sieve to obtain surface layer mixed powder;

s2, mixing Ti (C, N) cermet (the mass ratio of TiC to TiN is 6.5: 3.5), molybdenum, nickel and cobalt according to the mass ratio of 88: 4: 3: 5, adding absolute ethyl alcohol, ball-milling, fully mixing uniformly, drying in vacuum and sieving with a 100-mesh sieve to obtain matrix mixed powder;

s3, sequentially placing the surface layer mixed powder, the matrix mixed powder and the surface layer mixed powder into a grinding tool according to the mass ratio of 1: 12: 1, flattening by using a material rod when each layer is placed, ensuring the thickness of each layer to be uniform, and sealing by using graphite blocks after the material loading is finished;

s4, carrying out vacuum hot-pressing sintering, wherein the heating rate is 30 ℃/min, the sintering temperature is 1460 ℃, the heat preservation time is 32min, and the hot pressure is 36 Mpa;

s5 cutting the sintered product into needed size, grinding and polishing the surface with surface roughness Ra less than 0.1 μm.

Example 2

S1 reaction of TiB₂-TiC composite (TiB)₂The mass ratio of TiC to the powder is 6.5: 3.5), mixing vanadium carbide, molybdenum and nickel according to the mass ratio of 93: 3: 2, adding absolute ethyl alcohol, ball-milling, fully mixing uniformly, vacuum drying and sieving with a 100-mesh sieve to obtain surface layer mixed powder;

s2, mixing Ti (C, N) cermet (the mass ratio of TiC to TiN is 7.5: 2.5), molybdenum, nickel and cobalt according to the mass ratio of 86: 5: 4: 5, adding absolute ethyl alcohol, ball-milling, fully mixing uniformly, drying in vacuum and sieving with a 100-mesh sieve to obtain matrix mixed powder;

s3, sequentially placing the surface layer mixed powder, the matrix mixed powder and the surface layer mixed powder into a grinding tool according to the mass ratio of 1: 10: 1, flattening by using a material rod when each layer is placed, ensuring the thickness of each layer to be uniform, and sealing by using graphite blocks after the material loading is finished;

s4, carrying out vacuum hot-pressing sintering, wherein the heating rate is 28 ℃/min, the sintering temperature is 1490 ℃, the heat preservation time is 36min, and the hot pressure is 38 Mpa;

s5 cutting the sintered product into needed size, grinding and polishing the surface with surface roughness Ra less than 0.1 μm.

Example 3

S1 reaction of TiB₂-TiC composite (TiB)₂The mass ratio to TiC is 7.5: 2.5), mixing vanadium carbide, molybdenum and nickel according to the mass ratio of 92: 3: 2, adding absolute ethyl alcohol, ball-milling, fully mixing uniformly, vacuum drying and sieving with a 100-mesh sieve to obtain surface layer mixed powder;

s2, mixing Ti (C, N) cermet (the mass ratio of TiC to TiN is 7: 3), molybdenum, nickel and cobalt according to the mass ratio of 87: 3: 4: 6, adding absolute ethyl alcohol, ball-milling, fully mixing uniformly, drying in vacuum and sieving by a 100-mesh sieve to obtain matrix mixed powder;

s3, sequentially placing the surface layer mixed powder, the matrix mixed powder and the surface layer mixed powder into a grinding tool according to the mass ratio of 1: 13: 1, flattening by using a material rod when each layer is placed, ensuring the thickness of each layer to be uniform, and sealing by using graphite blocks after the material loading is finished;

s4, carrying out vacuum hot-pressing sintering, wherein the heating rate is 35 ℃/min, the sintering temperature is 1480 ℃, the heat preservation time is 38min, and the hot pressure is 32 Mpa;

s5 cutting the sintered product into needed size, grinding and polishing the surface with surface roughness Ra less than 0.1 μm.

The performance test method of the products obtained in the above examples 1 to 3 is as follows:

the bending strength of the product adopts a universal material testing machine, the span is set to be 20mm, and the loading rate is 0.5 mm/min; the hardness of the product adopts a Vickers hardness tester, the loading load is 9.8N, and the pressure maintaining time is 15 s; a diamond wire saw was used to prepare a 0.16mm wide kerf pre-crack, and a three-point bending experimental setup was used to measure the fracture toughness of the material, with the results listed in the following table:

as can be seen from the table, the comprehensive mechanical properties of the products of the present invention (examples 1-3) meet the use requirements of high-speed cutting tools.

The present embodiments are to be considered as illustrative and not restrictive, and the scope of the patent is to be determined by the appended claims.