WO2020113798A1

WO2020113798A1 - Long-service-life ultrathin sintering brazing hole drill for drilling of military armored kevlar layer and production process therefor

Info

Publication number: WO2020113798A1
Application number: PCT/CN2019/072509
Authority: WO
Inventors: 庄政伟; 庄敏伟; 杭海滨; 郑雷; 董香龙
Original assignee: 江苏锋菱超硬工具有限公司
Priority date: 2018-12-05
Filing date: 2019-01-21
Publication date: 2020-06-11
Also published as: CN109365879A

Abstract

A long-service-life ultrathin sintering brazing hole drill for drilling of a military armored Kevlar layer, comprising a working part (100) at the upper section and a mounting part (200) at the lower section, wherein the working part comprises a working section (101) at the upper section and a connecting section (102) at the lower section, a through hole penetrating from top to bottom is formed in the hole drill, a diamond layer (103) is provided at the top of the working section, the diamond layer is located on the outer side face and the end face of the top of the working section, and the diamond layer at the top of the working section is of a wavy tooth-shaped structure. The long-service-life ultrathin sintering brazing hole drill for the drilling of the military armored Kevlar layer is long in service life and high in cutting capacity. The present invention further relates to a production process for the long-service-life ultrathin sintering brazing hole drill for the drilling of the military armored Kevlar layer.

Description

[Name of invention formulated by ISA according to Rule 37.2] A long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling and its production process

Technical field

The invention relates to a long-life ultra-thin sintered brazed hole drill for drilling military armor Kevlar layer.

Background technique

The Kevlar layer used in military armor has a dense structure and high hardness. Using the current mainstream high-end diamond hole drill to open holes in this material is generally difficult to work for the following reasons:

1. The electroplated and brazed diamond hole drill has a high diamond concentration in the working part of about 200%. At the same time, the carcass has a strong grip on diamond; but it is generally a single-layer structure, so the initial use is sharp. Once the diamond is slightly worn , There is no diamond supplement in the follow-up, which leads to the waste of cutting halfway;

2. The sintered diamond hole drill belongs to the multi-layer diamond structure, but due to the limitation of the production process, the concentration of the working part generally does not exceed 100% (international concentration standard for diamond products). When used, the sharpness is insufficient, and the carcass is too hard, which will cause the subsequent diamonds to be out of use in time; the carcass is too soft, because the work object is too hard, the reaction force received by the working part will cause the carcass to wear quickly, and cannot continue working.

Summary of the invention

The purpose of the present invention is to overcome the above shortcomings and provide a long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling.

The purpose of the present invention is achieved as follows:

A long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling, characterized in that it includes an upper working section and a lower mounting section, wherein the working section includes an upper working section and a lower connecting section, The long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling is provided with through holes penetrating from top to bottom. The top of the working section is provided with a diamond layer. The diamond layer is located on the outer side and top of the top of the working section On the end face, the diamond layer on the top of the working section has a wavy tooth structure.

As a preference, the wave-shaped tooth structure includes spaced outer arc segments and inner arc segments, and adjacent outer arc segments and inner arc segments are connected by a transition arc segment.

As a preference, the diamond in the diamond layer adopts the following mixed diamond method: #70/80+#80/100+#100/120 three diamond mixing methods, the three particle size models are MBD10, three diamonds The number of particles floating up and down shall not exceed 20%.

As a preference, the carcass formulation of the working section is formulated according to parts by weight as follows: Co32-38 parts, Ni18-21 parts, CuSn20 alloy powder 13-15 parts, Cu14-17 parts, and NiCrP alloy powder 14-18 parts.

The production process of a long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling is as follows:

Step 1: Set the weight of each material in the working part according to the volume of the working part and referring to the bulk density of the metal powder and the density after melting;

Step 2: Determine the diamond concentration to be 150%;

Step 3: Mix the weighed metal powder and diamond in a sealed three-dimensional mixing cylinder;

Step 4: Put the mixed diamond and metal powder and matrix into the graphite mold;

Step 5: Cold press molding the product installed in the graphite mold, and then pressurizing and sintering it together with this mold in a medium frequency sintering furnace at a temperature of 680℃-720℃;

Step 6: Move the mold to a vacuum brazing furnace: braze at a temperature of 900℃-920℃ in an atmosphere with a vacuum degree higher than 3×10 ^-3 Pa to cause NiCrP alloy powder and diamond in the carcass Chemical metallurgical combination; then naturally cool to room temperature, take out the graphite mold, and remove the product from the mold;

Step 7. According to the requirements of the product drawings, the working department will carry out the sharpening process;

Step 8. The entire product surface is nickel plated to prevent rust;

Step 9. Packing after acceptance.

Compared with the prior art, the beneficial effects of the present invention are:

The invention provides a long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling and its production process has the advantages of long service life and strong cutting ability.

BRIEF DESCRIPTION

FIG. 1 is a schematic diagram of Embodiment 1 of a long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling.

FIG. 2 is a top plan view of FIG. 1.

FIG. 3 is a schematic diagram of Embodiment 2 of a long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling.

4 is a top plan view of FIG. 3.

FIG. 5 is a schematic diagram of Embodiment 3 of a long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling.

6 is a top plan view of FIG. 5.

7 is a schematic diagram of Embodiment 4 of a long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling.

FIG. 8 is a top plan view of FIG. 7.

detailed description

The technical solutions in the embodiments of the present invention will be described clearly and completely in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the invention, but not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without making creative efforts fall within the protection scope of the present invention.

1-8, the present invention relates to a long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling, which includes an upper working part 100 and a lower mounting part 200, military armor Kev The total length of the long-life ultra-thin sintered brazed hole drill for pulling layer drilling is 64.75mm, of which the working part 100 has a length of 34.25mm, the outer surface is matte, and the installation part 200 has a length of 30.5mm, the outer surface is bright, and the working part 100 includes an upper working section 101 and a lower connecting section 102, and a long-life ultra-thin sintered brazing hole drill for military armor Kevlar layer drilling is provided with through holes penetrating from top to bottom.

The top of the working section 101 is provided with a diamond layer 103 with a height of 4.5 mm-5.5 mm. The thickness of the diamond layer 103 is 0.05 mm-0.08 mm. The diamond layer 103 is located on the top outer side and top end surface of the working section 101. The diamond layer 103 on the top of the working section 101 has a wavy tooth structure. The wavy tooth structure includes spaced outer arc sections 103.1 and inner arc sections 103.2, and the adjacent outer arc sections and inner arc sections pass through the transition arc section 103.3 Connection.

A specific structure of a long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling uses the following four examples:

Example 1,

The outer diameter of the working part 100 is 5.86mm, the wall thickness is 0.5mm, the outer diameter of the mounting part 200 is 11.5mm, the lower part of the through hole is a 6mm inner diameter through hole with a height of 27.1mm, the height of the diamond layer 103 is 4.5mm, and the top surface of the diamond layer 103 includes Five sets of uniformly distributed outer arc segments and inner arc segments, the corresponding diameter of the outer arc segment is 6mm, the corresponding diameter of the inner arc segment is 4.75mm, the outer side of the transition arc segment has a transition radius of R0.2mm and R0.3mm, The inner side of the transition arc has a transition radius of R0.1mm and R0.5mm. For other parameters, see Figure 2.

Example 2.

The outer diameter of the working part 100 is 7.9mm, the wall thickness is 0.5mm, the outer diameter of the mounting part 200 is 11.5mm, the lower part of the through hole is a 6mm inner diameter through hole with a height of 41mm, the height of the diamond layer 103 is 5.5mm, and the top surface of the diamond layer 103 includes seven The outer arc segment and inner arc segment of the group are evenly distributed. The diameter of the outer arc segment is 8.05mm, the diameter of the inner arc segment is 6.8mm, and the outer side of the transition arc segment has a transition radius of R0.1mm and R0.4mm. The inner side of the transition arc has a transition radius of R0.1mm and R0.5mm. For other parameters, see Figure 4.

Example 3.

The outer diameter of the working part 100 is 9.86mm, the wall thickness is 0.5mm, the outer diameter of the mounting part 200 is 11.5mm, the lower part of the through hole is a 5.8mm inner diameter through hole with a height of 40.7mm, the height of the diamond layer 103 is 5.5mm, and the top surface of the diamond layer 103 Including nine sets of uniformly distributed outer arc segments and inner arc segments, the corresponding diameter of the outer arc segment is 10.05mm, the corresponding diameter of the inner arc segment is 8.8mm, the outer side of the transition arc segment has R0.1mm and R0.5mm transition Radius, the inner side of the transition arc has a transition radius of R0.1mm and R0.3mm. For other parameters, see Figure 6.

Example 4.

The outer diameter of the working part 100 is 11.9mm, the wall thickness is 0.5mm, the outer diameter of the mounting part 200 is 11.5mm, the lower part of the through hole is a 6mm inner diameter through hole with a height of 40.25mm, the height of the diamond layer 103 is 4.5mm, and the top surface of the diamond layer 103 includes Ten sets of uniformly distributed outer arc segments and inner arc segments, the corresponding diameter of the outer arc segment is 12.1mm, the corresponding diameter of the inner arc segment is 10.85mm, the outer side of the transition arc segment has a transition radius of R0.3mm, the transition arc segment The inner side of has a transition radius of R0.1mm and R0.4mm. For other parameters, see Figure 8.

A long-life ultra-thin sintered brazed hole drill production process for military armor Kevlar layer drilling is aimed at the problems in use of the current mainstream diamond hole drills in the above background technology, considering the following two aspects: on the one hand The drill must have a high concentration of electroplated and brazed hole drills. On the other hand, it must have a multi-layer structure of sintered hole drills. At the same time, the hardness and wear resistance of the carcass should be matched with the diamond layer: try to reach the diamond layer during use. At the same time wear and ensure continuous use of the blade, so it is designed to use a sintered hole drill to form and consolidate the working part, and then use brazing to make the diamond and the metal component in the carcass chemically and metallurgically combine to improve the combination of the diamond and the carcass force.

According to the above ideas, the following schemes are designed:

1. The choice of diamond, considering that the drilled hole needs to be smooth and clean, and it needs to be sharp and long-lived at the same time, using a mixed diamond method: #70/80+#80/100+#100/120 three diamond mixing methods (Diamonds produced by Henan Zhongnan Diamond Co., Ltd. have three particle sizes of MBD10). The working layer requires that the number of particles of the three types of diamonds is basically the same. The number of particles should not exceed 20%. The same concentration of diamonds, mixed particle size Use sharp;

2. The choice of diamond concentration, because this process involves sintering, if the diamond concentration is too high, the carcass cannot effectively hold the diamond, because the process includes the brazing process, according to the test, sintered diamond products can be used The limit concentration is 150% (international concentration standard for diamond products). In order to solve the problem of insufficient life, the use of increasing the diamond content in the working part is to increase the diamond concentration to compensate;

3. For the carcass formula, the metal powder (parts by weight) with high cobalt formula is selected for the reason of the workpiece material: Co32-38 parts, Ni18-21 parts, CuSn20 alloy powder 13-15 parts, Cu14-17 parts, NiCrP 14-18 parts of alloy powder;

4. Product design, considering the working conditions during use, especially the material is too dense and hard, the cooling of the hole drill is particularly important, so the high and low staggered wave tooth shape is designed in the working part of the hole drill, on the one hand, it is convenient for the coolant to be timely It enters the working part for cooling. On the other hand, this design helps to eliminate the debris, and it is not easy to produce the bad situation of burning the cutter head or using slip; at the same time, the substrate is made of 40Cr material: this material has good toughness and has a certain shock absorption function. ;

5. Mold design, because the workpiece is dense and hard, in order to improve the working efficiency of drilling, on the premise of ensuring the bonding strength of the working part of the product, the thinner the wall thickness of the working part, the better. The wall thickness of the working part designed for this is 0.4 +/-0.1mm, such ultra-thin structure and wavy tooth shape design can maximize the drilling speed.

Step 2: Determine the diamond concentration to be 150%. In the case where the three diamond particles are basically the same, determine the weight of the three diamonds according to the particle size of the diamond;

Step 3: Mix the weighed metal powder and diamond in a sealed three-dimensional mixing cylinder for more than 6 hours;

Step 4: Put the mixed diamond and metal powder and the substrate of 40Cr material into a graphite mold (the mold inner wall is coated with a release agent; to ensure the accuracy of use, this substrate of 40Cr material is produced by a CNC machining center);

Step 5: Cold-press molding the product loaded into the graphite mold, and then sinter it together with this mold in an intermediate frequency sintering furnace at a temperature of 680℃-720℃ for 10-20 minutes, preferably 15 minutes; (traditional simple sintering The sintering temperature of the process is above 800 ℃, this process reduces the sintering temperature.)

Step 6: Move the mold to a vacuum brazing furnace: braze at a temperature of 900℃-920℃ in an atmosphere with a vacuum degree higher than 3×10 ^-3 Pa, preferably 920℃, and keep it warm for 10 minutes, ( The traditional simple brazing process has a brazing temperature of 1000℃-1100℃, which reduces the brazing temperature.) The NiCrP alloy powder in the carcass is chemically metallurgically combined with diamond, which greatly improves the bonding force between diamond and carcass ; Then naturally cool to room temperature, take out the graphite mold, and remove the product from the mold;

Step 7. According to the requirements of the product drawings, the working department carries out "sharpening" treatment, and at the same time, the 40Cr base body is precision trimmed, and the concentricity of the product is not required to exceed 0.05mm;

Step 8. The entire product surface is nickel plated to prevent rust;

Step 9. Packing after acceptance.

For example, Example 1.

Step 1: Set the proportion and weight of each metal powder in the working part according to the volume of the working part 0.043CM ³ , and referring to the concentration of diamond and the bulk density and density of the metal powder required: Co35 parts 0.079 g , Ni20 parts 0.045 g, CuSn20 alloy powder 15 parts 0.034 g, Cu15 parts 0.034 g, NiCrP alloy powder 15 parts 0.034 g; (minimum production quantity 1000);

Step 2: Determine the diamond concentration to be 150%. When the three diamond particles are basically the same, determine the ratio and weight of the three diamonds according to the particle size of the diamond; #70/80 is 58 parts 0.033 grams, #80/ 100 is 30 servings 0.017 grams, #100/120 is 12 servings 0.007 grams; (minimum production quantity 1000);

Step 4: Put the mixed diamond and metal powder and 40Cr matrix into the graphite mold;

Step 5: Cold press molding the product installed in the graphite mold, and then pressurizing and sintering with the mold at a temperature of 700°C for 15 minutes in an intermediate frequency sintering furnace

Step 6: Move the mold to a vacuum brazing furnace: braze at a temperature of 910°C in an atmosphere with a vacuum higher than 3×10 ^-3 Pa, and keep it warm for 10 minutes, so that the NiCrP alloy powder in the carcass and The diamond is chemically metallurgically combined, which greatly improves the bonding force between the diamond and the carcass; then it is naturally cooled to room temperature, the graphite mold is taken out, and the product is demolded and removed;

Step 8. The entire product surface is nickel plated to prevent rust;

Step 9. Packing after acceptance.

Example 2

Step 1: Set the proportion and weight of each metal powder in the working part according to the volume of the working part 0.043CM ³ , and referring to the concentration of diamond and the bulk density and density of the metal powder required: Co32 parts 0.072 g , Ni18 parts 0.041 g, CuSn20 alloy powder 15 parts 0.034 g, Cu17 parts 0.038 g, NiCrP alloy powder 18 parts 0.041 g; (minimum production quantity 1000);

Step 5: Cold press molding the product installed in the graphite mold, and then pressurize and sinter it together with this mold in a medium frequency sintering furnace at a temperature of 680°C for 15 minutes;

Step 6: Move the mold to a vacuum brazing furnace: braze at 900°C in an atmosphere with a vacuum degree higher than 3×10 ^-3 Pa, and keep it warm for 10 minutes, so that the NiCrP alloy powder in the carcass is The diamond is chemically metallurgically combined, which greatly improves the bonding force between the diamond and the carcass; then it is naturally cooled to room temperature, the graphite mold is taken out, and the product is demolded and removed;

Step 7. According to the requirements of the product drawings, the work department performs "sharpening" treatment, and at the same time, the 40Cr base body is precision trimmed, which requires the product's concentricity to not exceed 0.05mm;

Step 8. The entire product surface is nickel plated to prevent rust;

Step 9. Packing after acceptance.

Example three

Step 1: Set the proportion and weight of each metal powder in the working part according to the volume of the working part 0.043CM ³ , and referring to the concentration of diamond and the bulk density and density of the metal powder required: Co38 parts 0.086 g , Ni21 parts 0.047 g, CuSn20 alloy powder 13 parts 0.029 g, Cu14 parts 0.032 g, NiCrP alloy powder 14 parts 0.032 g; (minimum production quantity 1000);

Step 5: Cold press molding the product installed in the graphite mold, and then pressurizing and sintering together with this mold in an intermediate frequency sintering furnace at a temperature of 720°C for 15 minutes;

Step 6: Move the mold to a vacuum brazing furnace: braze at a temperature of 920°C in a vacuum with a degree of vacuum higher than 3×10 ^-3 Pa, and keep it warm for 10 minutes to make the NiCrP alloy powder in the carcass and The diamond is chemically metallurgically combined, which greatly improves the bonding force between the diamond and the carcass; then it is naturally cooled to room temperature, the graphite mold is taken out, and the product is demolded and removed;

Step 8. The entire product surface is nickel plated to prevent rust;

Step 9. Packing after acceptance.

According to the above three groups of examples and the best performance brazed diamond hole drill and sintered diamond hole drill on the market, an experimental comparison is made:

Test conditions:

Experimental equipment: XH715D vertical machining center, spindle motor power: 7.5/11KW, spindle output torque: 35.8/70.3Nm, spindle speed: 60～8000rpm.

Cooling: emulsion

Experimental parameter range (Aperture 8mm):

Material: 6mm thick SiC ultra-high hardness ceramics;

Recommended feed speed (mm/min): 10-14;

Recommended spindle speed (r/min): 6000-6500.

test results:

Tool life of the first embodiment: 120-150 holes;

Tool life of the second embodiment: 105-120 holes;

Tool life of the third embodiment: 110-125 holes;

Tool life of brazed diamond hole drill (8MM diameter, #70/80 grain size): 3-6 holes;

Tool life of sintered diamond hole drill (8MM diameter, #70/80 grain size): 2-4 holes (the difference is that the recommended feed rate is 6-8mm/min).

From the above comparative test results, it can be seen that the composite technology of sintering and brazing and the combination of the above formulas make the performance of the manufactured diamond hole drill far greater than the traditional best brazed diamond hole drill and sintered diamond on the market The performance of hole drilling.

The above are only specific application examples of the present invention, and do not limit the protection scope of the present invention. All technical solutions formed by equivalent transformation or equivalent replacement fall within the protection scope of the present invention.

Claims

A long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling, characterized in that it includes an upper working section and a lower mounting section, wherein the working section includes an upper working section and a lower connecting section, The long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling is provided with through holes penetrating from top to bottom. The top of the working section is provided with a diamond layer. The diamond layer is located on the outer side and top of the top of the working section On the end face, the diamond layer on the top of the working section has a wavy tooth structure.
A long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling according to claim 1, characterized in that the wavy tooth structure includes spaced outer arc segments and inner arc segments, adjacent The outer arc segment and the inner arc segment are connected by a transition arc segment.
The long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling according to claim 1, wherein the diamond in the diamond layer adopts the following mixed diamond method: #70/80+#80 /100+#100/120 Three diamond mixing methods, the three particle sizes are all MBD10, and the number of particles of the three diamonds should not exceed 20%.
The long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling according to claim 1, characterized in that the formula of the carcass of the working section is as follows according to the weight parts: Co32-38 parts, Ni18-21 parts, CuSn20 alloy powder 13-15 parts, Cu14-17 parts, NiCrP alloy powder 14-18 parts.
A production process of long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling is characterized in that the sintering process is performed first and then the brazing process is performed.
A production process of long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling according to claim 5 is characterized in that the sintering temperature is 680℃-720℃ and the brazing temperature is 900℃- 920℃.
The production process of a long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling according to claim 5 is as follows:

Step 1: Set the weight of each material in the working part according to the volume of the working part and referring to the bulk density of the metal powder and the density after melting;

Step 2: Determine the diamond concentration to be 150%;

Step 3: Mix the weighed metal powder and diamond in a sealed three-dimensional mixing cylinder;

Step 4: Put the mixed diamond and metal powder and matrix into the graphite mold;

Step 5: Cold press molding the product installed in the graphite mold, and then pressurizing and sintering it together with this mold in the intermediate frequency sintering furnace at a temperature of 680℃-720℃;

Step 6: Move the mold to a vacuum brazing furnace: braze at a temperature of 900℃-920℃ in an atmosphere with a vacuum higher than 3×10 -3 Pa to cause NiCrP alloy powder and diamond in the carcass Chemical metallurgical combination; then naturally cool to room temperature, take out the graphite mold, and remove the product from the mold;

Step 7. According to the requirements of the product drawings, the working department will carry out the sharpening process;

Step 8. The entire product surface is nickel plated to prevent rust;

Step 9. Packing after acceptance.
The production process of long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling according to claim 8, characterized in that the diamond adopts the following mixed diamond method: #70/80+#80/ 100+#100/120 Three diamond mixing methods, the three particle sizes are all MBD10, and the number of particles of the three diamonds should not fluctuate more than 20%.
The production process of long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling according to claim 8, characterized in that the formula of the carcass according to the weight parts is as follows: Co32-38 parts, Ni18-21 parts, CuSn20 alloy powder 13-15 parts, Cu14-17 parts, NiCrP alloy powder 14-18 parts.
The production process of long-life ultra-thin sintered brazed hole drill for military armor Kevlar layer drilling according to claim 8, characterized in that the base body is made of 40Cr material.