WO2021017323A1

WO2021017323A1 - Method for preparing diamond tool

Info

Publication number: WO2021017323A1
Application number: PCT/CN2019/119360
Authority: WO
Inventors: 张明军; 王志军; 胡永乐; 毛聪; 张健; 唐昆; 曹太山
Original assignee: 长沙理工大学
Priority date: 2019-07-30
Filing date: 2019-11-19
Publication date: 2021-02-04
Also published as: CN110396688B; CN110396688A

Abstract

The present invention relates to a method for preparing a diamond tool, characterized in: step 1, providing a base plate of a diamond tool; step 2, providing diamond particles; step 3, providing an alloy powder; step 4, providing a laser-based manufacturing system; step 5, starting the laser-based manufacturing system; step 6, cladding a thin layer of the alloy powder on the surface of the base layer in a high-power continuous laser coaxial powder feeding mode, and simultaneously starting a diamond jetting device; step 7, completing laser brazing and turning off the diamond jetting device; step 8, starting a dusting device; step 9, scanning a test piece with short pulse laser light; step 10, repeating the above steps 8 and 9 several times to obtain a diamond tool consolidated abrasive layer; step 11, turning off the laser-based manufacturing system; and step 12, placing the prepared diamond tool into a heating furnace to perform post-processing to complete the diamond tool preparation process. Compared with the prior art, the diamond tool prepared by the present invention has good bonding properties, small thermal effects, and high processing efficiency.

Description

Method for preparing diamond tool

Technical field

The invention belongs to the technical field of mechanical manufacturing, and specifically relates to a method for preparing a diamond tool.

Background technique

Diamond has the highest hardness, rigidity and excellent wear resistance, corrosion resistance and chemical stability, making diamond widely used in various grinding tools. At present, many scholars study the brazing process to prepare single-layer super-hard abrasive tools. Compared with multi-layer sintered super-hard abrasive tools and single-layer electroplated super-hard abrasive tools, brazed super-hard abrasive tools can achieve metallurgical and chemical bonding between the abrasive, brazing filler metal and matrix, thereby improving the bonding strength and the use of tools. long life. In addition, the exposed height of the particles increases, the chip holding space increases, and it is not easy to block.

The manufacturing process of this new technology is mainly completed by brazing in the furnace, and the time-consuming brazing process may cause damage to the diamond particles and deformation of the tool matrix. In addition, the size of the brazing furnace also limits the size of the diamond particles. The use of high frequency induction brazing avoids the limitations of the above process, but it is difficult to control the heating rate and heating range.

It was published on August 07, 2013. The invention patent "A new type of nickel-based brazing single-layer diamond grinding wheel" with the announcement number CN 103231064 A discloses a manufacturing method of brazing single-layer diamond grinding wheel. The invention reduces the brazing temperature by adding fine Al powder to the Ni-Cr-based brazing filler metal, and solves the problems of diamond thermal damage and matrix deformation, but this method does not solve the problem that large-size grinding wheels cannot be directly brazed.

Published on September 9, 2015, the invention patent "Single layer high temperature brazing diamond grinding wheel process" with the announcement number CN 104889518 A discloses a single layer high temperature brazing diamond grinding wheel process. The invention first uses gas welding to spray 1mm on the metal substrate. The 1.5mm-thick Ni-Cr alloy layer solves the problem of poor wettability between the alloy layer and the metal substrate. However, this method still has problems such as difficulty in controlling the heating rate and heating range in induction brazing.

In recent years, laser welding has become a research hotspot in the field of welding at home and abroad due to its low total heat input, rapid welding process, and small heat-affected zone. Laser brazing technology has attracted more and more attention. The study found that laser brazing can be heated in selected areas, the heat affected zone is small, and it is easy to control. After brazing, it can ensure that the substrate (especially the thin plate substrate) is basically not deformed, which can compensate for the brazing in the vacuum furnace and the high-frequency induction brazing process. The above problems exist in. However, during the laser brazing diamond experiment, it was found that the diamond would move along with the molten pool, and finally the diamond would aggregate into piles, which caused severe thermal damage to the diamond, and the diamond could not be brazed to the preset position. To the ideal diamond arrangement sequence. In addition, in the conventional laser brazing process of diamond, the laser is directly projected on the diamond surface, which increases the possibility of burning, oxidation and graphitization of the diamond surface, resulting in a decrease in the bonding strength between the solder layer and the diamond.

Summary of the invention

The purpose of the present invention is to provide a method for preparing diamond tools, which has the remarkable advantages of good diamond bonding performance, low heat input, high efficiency and the like.

The present invention provides a method for preparing a diamond tool, including the following steps: Step 1. Provide a diamond tool substrate.

Step 2. Provide diamond particles.

Step 3. Provide alloy powder.

Step 4. Provide a laser manufacturing system.

Step 5. Start the laser manufacturing system, and use the high-power continuous laser coaxial powder feeding mode to cladding a base layer on the diamond tool substrate.

Step 6. Use the high-power continuous laser coaxial powder feeding mode to cladding a thin layer of alloy powder on the surface of the base layer, and at the same time, start the diamond spray device to spray diamond particles to the molten alloy powder area to realize the brazed connection and fixation of the diamond and the alloy powder.

Step 7. Finish the laser brazing and turn off the diamond jetting device.

Step 8. Start the powder spreading device, and evenly spread the alloy powder on the surface of the laser brazing test piece to obtain a thin alloy powder layer.

Step 9. Use a short-pulse laser to scan the test piece to melt the thin alloy powder layer and combine with the diamond particles. Step 10. Repeat the above steps 8 and 9 several times to obtain a diamond tool consolidated abrasive layer.

Step 11. Turn off the laser manufacturing system.

Step 12: Put the prepared diamond tool into a heating furnace for post-processing to complete the diamond tool preparation process.

In one of the embodiments, in step 1, the substrate is 45 steel.

In one of the embodiments, in step 2, the diamond particles are artificial hexagonal diamonds with a size of 15-55 mesh.

In one of the embodiments, in step 3, the alloy powder is Ni-Cr alloy powder with a size of 200 mesh. In one of the embodiments, in step 4, the laser manufacturing system includes a high-power continuous laser, a short pulse laser, a first transmission fiber, a second transmission fiber, a first laser working head, a second laser working head, and a diamond jet Device, dusting device, etc.

In one of the embodiments, in step 4, the high-power continuous laser is connected to the first laser working head through the first transmission fiber, and laser brazing can be realized.

In one of the embodiments, in step 4, the high-power continuous laser may be a fiber laser, a disc laser or a semiconductor laser.

In one of the embodiments, in step 4, the high-power continuous laser power is 500-2000W.

In one of the embodiments, in step 4, the first laser working head can realize coaxial powder feeding and coaxial blowing of welding shielding gas.

In one of the embodiments, in step 4, the short-pulse laser is connected to the second laser working head through the second transmission fiber, so that laser micromachining can be realized.

In one of the embodiments, in step 4, the short-pulse laser may be a nanosecond laser or a picosecond laser. In one of the embodiments, in step 4, the short-pulse laser power is 100-500W.

In one of the embodiments, in step 5, the first laser beam formed by high-power continuous laser focusing is cladding a base layer.

In one of the embodiments, in step 6, the thickness d1 of the thin brazing layer obtained by cladding a thin layer of alloy powder on the surface of the base layer is about 0.05 to 0.1 mm.

In one of the embodiments, in step 8, the thickness d2 of the thin alloy powder layer spread on the surface of the test piece by the powder spreading device is about 0.01 to 0.05 mm.

In one of the embodiments, in step 9, the second laser beam formed by the short-pulse laser focusing scans the test piece to melt the thin alloy powder layer.

In one of the embodiments, in step 12, after inserting the diamond tools, the heating furnace is filled with argon gas, heated from room temperature to 600-800° C. for 5 minutes, and then cooled to room temperature with the furnace.

The invention has the following beneficial effects:

1. In the present invention, the short-pulse laser additive manufacturing technology is used to prepare the diamond tool consolidated abrasive layer, that is, the short-pulse laser is used to melt the thin alloy powder layer and combine it with diamond particles. The heat input of the preparation process is small, and the diamond The thermal damage is small, and the residual stress of the abrasive layer is small.

2. In the present invention, a high-power continuous laser is used to melt an extremely thin alloy powder layer, and diamond particles are sprayed into the molten alloy powder layer to obtain a thin brazing layer, which effectively fixes the diamond particles and is a short-pulse laser multilayer The preparation of the consolidated abrasive layer provides feasible conditions.

3. In the present invention, the method of combining high-power continuous laser and short-pulse laser is used to prepare diamond tools, which has both efficiency and performance.

Description of the drawings

Figure 1 Schematic diagram of the high-power continuous laser brazing process in the scheme of the present invention.

Figure 2 is a partial schematic diagram of the process of melting alloy powder with a short pulse laser in the scheme of the present invention.

Figure 3 is a partial schematic diagram of a diamond tool prepared by the present invention.

In the picture: 1. Substrate, 2. Base layer, 3. Thin brazing layer, 4. Molten alloy powder, 5. Alloy powder flow, 6. Diamond particles, 7. Diamond jet device, 8. First laser working head, 9. , Protective air flow, 10, the first laser beam, 11, the consolidated abrasive layer, 12, the second laser working head, 13, the second laser beam, 14, the thin alloy powder layer.

Detailed ways

The technical solution of the present invention will be described in detail below with reference to the accompanying drawings 1-3 and specific embodiments.

As shown in FIGS. 1-3, in an embodiment of the present invention, a method for manufacturing a diamond tool based on laser manufacturing technology includes the following steps.

Step 1. Provide a substrate 1 of the diamond tool. Optionally, the base plate 1 is 45 steel.

Step 2. Provide diamond particles 6.

Optionally, the diamond particles 6 are artificial hexagonal diamonds with a size of 15-55 mesh. Step 3. Provide alloy powder.

Optionally, the alloy powder size is 200 mesh. Step 4. Provide a laser manufacturing system.

Optionally, the laser manufacturing system includes a high-power continuous laser, a short-pulse laser, a first transmission fiber, a second transmission fiber, a first laser working head 8, a second laser working head 12, a diamond jetting device 7, a dusting device, etc. .

Optionally, the high-power continuous laser is connected to the first laser working head 8 through the first transmission fiber to realize laser brazing.

Optionally, the high-power continuous laser may be a fiber laser, a disc laser or a semiconductor laser. Optionally, the high-power continuous laser power is 500-2000W.

Optionally, the first laser working head 8 can realize coaxial powder feeding and coaxial blowing of welding shielding gas. Optionally, the gas flow rate of coaxially blowing welding shielding gas is 2～4L/min.

Optionally, the short-pulse laser is connected to the second laser working head 12 through the second transmission fiber, which can realize laser micro processing.

Optionally, the short pulse laser may be a nanosecond laser or a picosecond laser. Optionally, the short-pulse laser power is 100-500W.

Step 5: Start the laser manufacturing system, and use the high-power continuous laser coaxial powder feeding mode to cladding a base layer 2 on the diamond tool substrate 1.

Step 6. Use the high-power continuous laser coaxial powder feeding mode to cladding a thin alloy powder layer 14 on the surface of the base layer 2. At the same time, start the diamond injection device 7 to spray diamond particles 6 to the molten alloy powder 4 area to achieve gold

The rigid stone particles 6 are connected and fixed with the thin brazing layer 3.

Optionally, the thickness d1 of the thin brazing layer 3 obtained by cladding a thin alloy powder layer 14 on the surface of the base layer 2 is about 0.05-0.1 mm.

Step 7. Finish the laser brazing and turn off the diamond jet device 7.

Step 8. Start the powder spreading device, and evenly spread the alloy powder on the surface of the laser brazing test piece to obtain a thin alloy powder layer 14.

Optionally, the thickness d2 of the thin alloy powder layer 14 spread on the surface of the test piece by the powder spreading device is about 0.01-0.05 mm. Step 9: Scan the test piece with a short pulse laser to realize the melting and bonding of the thin alloy powder layer 14 with the diamond particles 6.

Step 10: Repeat the above steps 8 and 9 several times to obtain the diamond tool consolidated abrasive layer 11. Step 11. Turn off the laser manufacturing system.

Step 12. Put the prepared diamond tool into a heating furnace for post-processing to complete the diamond tool preparation process.

Optionally, after inserting the diamond tools, the heating furnace is filled with argon gas, heated from room temperature to 600-800°C, kept for 5 minutes, and then cooled to room temperature along with the furnace.

In the present invention, the short-pulse laser additive manufacturing technology is used to prepare the diamond tool consolidated abrasive layer 11, that is, the short-pulse laser is used to melt the thin alloy powder layer 14 and combine it with the diamond particles 6, and the heat input of the preparation process is small. Diamond thermal damage is small, and the residual stress of the abrasive layer is small. In addition, the combination of high-power continuous laser and short-pulse laser is used to prepare diamond tools with both efficiency and performance.

The above-mentioned embodiment is one of the embodiments of the present invention, but the embodiment of the present invention is not limited by the above-mentioned embodiment. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principle of the present invention shall be regarded as equivalent replacement methods and shall be included in the protection scope of the present invention.

Claims

A method for preparing diamond tools includes the following steps:

Step 1. Provide the diamond tool substrate (1);

Step 2. Provide diamond particles (6);

Step 3. Provide alloy powder;

Step 4. Provide laser manufacturing system;

Step 5. Start the laser manufacturing system, and use the high-power continuous laser coaxial powder feeding mode to cladding a base layer (2) on the diamond tool substrate (1);

Step 6. Use high-power continuous laser coaxial powder feeding mode to cladding a thin alloy powder layer (14) on the surface of the base layer (2); at the same time, start the diamond injection device (7) to spray diamond to the molten alloy powder (4) area The particles (6) realize the brazing connection and fixing of the diamond particles (6) and the alloy powder.

Step 7. Finish the laser brazing and turn off the diamond jetting device (7);

Step 8. Start the powder spreading device, and evenly spread the alloy powder on the surface of the laser brazing test piece to obtain a thin alloy powder layer (14);

Step 9. Use a short pulse laser to scan the test piece to melt the thin alloy powder layer (14) and combine with the diamond particles (6).

Step 10: Repeat the above steps 8 and 9 several times to obtain the diamond tool consolidated abrasive layer (11).

Step 11. Turn off the laser manufacturing system.

Step 12: Put the prepared diamond tool into a heating furnace for post-processing to complete the diamond tool preparation process.
The method for preparing a diamond tool according to claim 1, wherein in step 4, the laser manufacturing system includes a high-power continuous laser, a short pulse laser, a first transmission fiber, a second transmission fiber, and a first laser working head (8 ), the second laser working head (12), diamond jetting device (7), dusting device, etc. 3. The method for preparing a diamond tool according to claim 1, wherein in step 4, the high-power continuous laser power is 0.5-2kW.
The method for preparing a diamond tool according to claim 1, wherein in step 4, the first laser working head (8) can realize coaxial powder feeding and coaxial blowing of welding shielding gas.
The method for preparing a diamond tool according to claim 1, wherein in step 4, the short pulse laser power is 0.1-0.5 kW.
The method for preparing a diamond tool according to claim 1, wherein in step 6, a thin alloy powder layer (14) is cladding on the surface of the base layer (2) to obtain a thin brazing layer (3) with a thickness d 1 about It is 0.05～0.1mm.
The method for preparing a diamond tool according to claim 1, wherein in step 8, the thickness d 2 of the thin alloy powder layer (14) spread on the surface of the test piece by the powder spreading device is about 0.01-0.05 mm.
The method for preparing diamond tools according to claim 1, characterized in that, in step 12, after inserting the diamond tools, the heating furnace is filled with argon gas, heated from room temperature to 600-800°C for 5 minutes, and then cooled to room temperature with the furnace .