A synthetic process for monolithic blades

Abstract

The application discloses a synthetic process of an integral blade, relates to the field of superhard material tools, and comprises the following steps: S1, feeding: placing a pre-pressed blade assembly block in a cubic press for synthesis; S2, pressure increasing: after liquid charging of the cubic press is completed, the pressure is increased to 90 MPa in 200 seconds; S3, superpressure synthesis: in the superpressure process, the power is increased to the maximum power of 10 kW in 210 seconds; S4, sintering: pressure maintaining and constant-power synthesis are performed for 600 seconds, and sintering is performed by maintaining 10 kW; S5, pressure and temperature decreasing: the pressure is decreased from 90 MPa to 30 MPa in 300 seconds, and the power is decreased from 10 kW to 0, and the pressure and temperature are slowly decreased; S6, pressure releasing and returning: the pressure is released and returned below 30 MPa, and the whole sintering process is completed. The application improves the superpressure synthesis and the pressure and temperature decreasing process in the synthetic process, effectively improves the blade yield, is high in product quality, greatly reduces the production cost, and solves the problems of uneven hardness and easy production of waste and broken blades in the sintering process of the integral blade.

Description

Technical Field

[0001] This invention relates to the field of superhard material tools, and in particular to a synthesis process for a monolithic cutting blade. Background Technology

[0002] Integral polycrystalline cubic boron nitride (CBN) inserts are made from CBN micro-powder sintered into a block material, which is then ground into inserts. They are collectively referred to as cubic boron nitride inserts, along with cubic boron nitride composite inserts. Integral polycrystalline cubic boron nitride inserts lack a center locating hole and groove; their dimensional parameters and precision are identical to those of carbide inserts. They are indexable inserts, often used in conjunction with cubic boron nitride turning tool holders. They possess the characteristics of polycrystalline cubic boron nitride, such as high hardness, chemical inertness, and thermal stability. Compared to welded cubic boron nitride composite inserts, they have a longer cutting edge and higher toughness, thus allowing for both finishing and roughing operations. Integral polycrystalline cubic boron nitride inserts can... It can machine materials that are difficult to machine with traditional tools, such as hardened steel, mold steel, tool steel, alloy steel, gray cast iron, white cast iron, cemented carbide, and ceramics with a hardness of HRC60 or above. It has unique characteristics and applications in interrupted cutting and roughing. It is suitable for general machine tools, special machine tools, automatic lines and CNC machine tools. It is widely used in cutting processes in military, automotive, metallurgical rolls, bearings, molds and other industries. Its service life is 5 to 25 times that of cemented carbide tools. Its high wear resistance greatly reduces the number of tool changes and sharpening. It can also perform dry high-speed cutting without coolant, which meets the increasingly important national environmental protection requirements and the requirements of "low-carbon economy".

[0003] Based on the inherent physical advantages of cubic boron nitride integral polycrystalline cutting inserts, and with the continuous research and improvement of related technologies, cubic boron nitride integral polycrystalline cutting inserts have extremely high development and application value in the field of cutting technology. However, the existing processing technology for cubic boron nitride integral polycrystalline cutting inserts is not perfect. The basic process involves high-pressure sintering of pre-pressed inserts to form finished inserts. The yield of inserts after processing by the current process is about 90%, and there is still room for process improvement to increase the yield.

[0004] Therefore, it is necessary to invent a synthesis process for integral blades to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a process for synthesizing a monolithic blade to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a process for synthesizing an integral blade, comprising:

[0007] S1 Feeding: Place the pre-pressed blade assembly block into a six-sided press for assembly;

[0008] S2 pressure boost: The pressure rises to 90 MPa 200 seconds after the six-sided top press is filled with liquid;

[0009] S3 Overpressure Synthesis: During the overpressure process, the power reaches the maximum of 10 kilowatts within 210 seconds;

[0010] S4 sintering: constant pressure and power synthesis for 600 seconds, maintaining 10 kilowatts for sintering;

[0011] S5 pressure reduction and cooling: The pressure drops from 90 MPa to 30 MPa in 300 seconds, while the power drops from 10 kW to 0, resulting in slow pressure reduction and cooling.

[0012] S6 depressurization return: Depressurization return below 30 MPa completes the entire sintering process.

[0013] Optionally, the S3 overpressure synthesis includes three stages: the first stage increases the power to 5 kW within 60 seconds, the second stage increases it to 7 kW within 60 seconds, and the third stage increases it to the maximum power of 10 kW within 90 seconds.

[0014] Optionally, the top hammer of the six-sided top press is adjusted to 0.5 kg / 10,000 cycles.

[0015] The technical effects and advantages of this invention are as follows:

[0016] This invention improves the overpressure synthesis and depressurization / cooling stages of the synthesis process, effectively increasing the yield of blades, resulting in high product quality, and significantly reducing production costs. It also solves the problem of uneven hardness during the sintering of integral blades, which easily leads to defective or cracked blades. Detailed Implementation

[0017] The embodiments described in this invention are merely some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0018] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0019] This invention provides a synthesis process for integral cutting tools, mainly used for the processing of cubic boron nitride integral polycrystalline cutting tools;

[0020] Traditional processing mainly includes: placing the pre-pressed blade assembly blocks into a six-sided press for assembly, the top hammer of the six-sided press is 1 kg / 10,000 times, the six-sided press is pressurized, the power is rapidly increased to the maximum power or the maximum power is directly used for sintering, the maximum power is maintained for sintering, and after sintering is completed, the power is directly reduced to zero to cool down, and then the pressure is released and the six-sided press is shut down.

[0021] The average yield of blades produced by this process is 90%.

[0022] The manufacturing process of this integral blade:

[0023] include:

[0024] S1 Feeding: Place the pre-pressed blade assembly block into the six-sided top press for assembly. Adjust the top hammer of the six-sided top press to 0.5 kg / 10,000 times. The normal service life is more than 20,000 times, and the maximum is 30,000 times.

[0025] S2 pressure boost: The pressure rises to 90 MPa 200 seconds after the six-sided top press is filled with liquid;

[0026] S3 Overpressure Synthesis: During the overpressure process, the power is increased to the maximum of 10 kW within 210 seconds. Overpressure synthesis includes three stages. The first stage is the power increase to 5 kW within 60 seconds, which is the preheating stage. The second stage is the power increase to 7 kW within 60 seconds, which is the mutual dissolution stage. The third stage is the power increase to the maximum of 10 kW within 90 seconds, which is the heat preservation synthesis.

[0027] S4 sintering: Hold pressure and constant power for 600 seconds, maintain 10 kilowatts for sintering, this stage is the holding pressure and constant power sintering stage;

[0028] S5 Pressure Reduction and Temperature Reduction: 300 seconds after sintering, the pressure drops from 90 MPa to 30 MPa while the power drops from 10 kW to 0, slowly reducing pressure and temperature;

[0029] S6 depressurization return: Depressurization return below 30 MPa completes the entire sintering process.

[0030] This invention also provides a finished product multiple sampling inspection record form, in which 100 products are sampled each time to check the yield rate, as shown in the table below:

[0031] Sampled batches 1 2 3 4 5 Qualified quantity 98 97 97 96 97

[0032] The yield rate of this process is 97%;

[0033] The present invention improves the process of overpressure synthesis and depressurization / cooling stages. Overpressure synthesis is divided into three stages: preheating stage, mutual dissolution stage, and heat preservation synthesis, gradually increasing the power. In the depressurization / cooling stage, the pressure and temperature are slowly and steadily reduced, which effectively improves the yield of blades, resulting in high product quality and greatly reducing production costs. It also solves the problem of uneven hardness during the sintering process of the whole blade, which easily leads to defective and cracked blades.

[0034] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A process for synthesizing a single-piece blade, characterized in that, include: S1 Feeding: Place the pre-pressed blade assembly block into the six-sided top press for assembly, and adjust the top hammer of the six-sided top press to 0.5 kg / 10,000 times; S2 pressure boost: The pressure rises to 90 MPa 200 seconds after the six-sided top press is filled with liquid; S3 Overpressure Synthesis: During the overpressure process, the power is increased to the maximum power of 10 kW within 210 seconds. The overpressure synthesis includes three stages: the power is increased to 5 kW within 60 seconds in the first stage, the power is increased to 7 kW again within 60 seconds in the second stage, and the power is increased to the maximum power of 10 kW within 90 seconds in the third stage. S4 sintering: constant pressure and power synthesis for 600 seconds, maintaining 10 kilowatts for sintering; S5 pressure reduction and cooling: The pressure drops from 90 MPa to 30 MPa in 300 seconds, while the power drops from 10 kW to 0, resulting in slow pressure reduction and cooling. S6 depressurization return: Depressurization return below 30 MPa completes the entire sintering process.