WO2024069386A1

WO2024069386A1 - Knife and manufacturing method therefor

Info

Publication number: WO2024069386A1
Application number: PCT/IB2023/059495
Authority: WO
Inventors: 瞿义生
Original assignee: 武汉苏泊尔炊具有限公司
Priority date: 2022-09-29
Filing date: 2023-09-26
Publication date: 2024-04-04
Also published as: CN115533968A

Abstract

A knife (100) and a manufacturing method therefor. The knife (100) comprises: a body portion (10) made of a matrix material or a composite material; and a blade portion (20), which is made of the composite material and joined to the body portion (10), wherein the composite material comprises the matrix material and hard ceramic particles uniformly distributed in the matrix material, and the hard ceramic particles have a higher melting point than the matrix material. The knife (100) has improved long-lasting sharpness.

Description

Knife and its manufacturing method TECHNICAL FIELD The present invention relates to the field of knives, and more specifically, to a knife and its manufacturing method. BACKGROUND Knife is one of the instruments that people often need to use in daily life. The sharpness of the knife is the main factor to consider the performance of the knife. At present, the common knives on the market are martensitic stainless steel knives, which are one of the knives with better performance. However, this type of knife still has the following disadvantages: the cutting edge of the knife is usually a thinner conical structure. In daily use, the cutting edge will inevitably hit the hard material (for example, a cutting board, a bone), and after a period of use, there will be obvious bending (i.e., curling) at the cutting edge. In addition, the sharpness of the cutting edge of the martensitic stainless steel knife will also be significantly reduced after a short period of use due to wear. Therefore, how to make the knife lastingly sharp is the direction that has been explored in the field of knife manufacturing technology. SUMMARY OF THE INVENTION The purpose of the present invention is to provide a knife and a manufacturing method thereof to solve the problem of insufficient lasting sharpness of knives in the prior art. The tool according to the present invention comprises: a main body, made of a matrix material or a composite material; and a blade, made of the composite material and bonded to the main body, wherein the composite material comprises the matrix material and hard ceramic particles uniformly distributed in the matrix material, wherein the hard ceramic particles have a higher melting point than the matrix material. In an embodiment, the matrix material comprises at least one of martensitic stainless steel, austenitic stainless steel and duplex stainless steel. In an embodiment, the hard ceramic particles comprise at least one of calcium carbide, silicon carbide, zirconium oxide, aluminum oxide, chromium carbide, titanium oxide, titanium carbide and silicon nitride. In an embodiment, the particle size of the hard ceramic particles is in the range of 20|im-100|im. In an embodiment, based on the total mass of the composite material, the mass of the matrix material is 20|im-100|im. The percentage is 70%-90%, and the mass percentage of hard ceramic particles is 10%-30% _. The method for manufacturing the above-mentioned tool according to an embodiment of the present invention includes: mixing matrix material powder and hard ceramic particles uniformly through a ball milling mixing process to manufacture a composite material slurry, and preparing a dry composite material powder through a spray powdering method; pressing the composite material powder in a mold to form a tool embryo or pressing the matrix material powder and the composite material powder in a mold to form a tool embryo, wherein the part of the tool embryo corresponding to the blade of the tool is made of composite material, and the part of the tool embryo corresponding to the main body of the tool is made of matrix material or composite material; sintering the tool embryo in a protective atmosphere so that the matrix material is melted and the hard ceramic particles remain in a particle state; and grinding and sharpening the tool embryo after cooling. In an embodiment, the particle size of the matrix material powder and the hard ceramic particles are both in the range of 20|im-100|im. In an embodiment, the mass percentage of the matrix material powder in the composite material powder is 70%-90%, and the mass percentage of the hard ceramic particles is 10%-30%. In an embodiment, the molding pressure when pressing to form the tool blank is 200MPa-500MPa _. According to another embodiment of the present invention, a method for manufacturing the above-mentioned tool includes: manufacturing a main body and a blade separately, and then combining the blade to the main body. According to the concept of the present invention, the blade of the tool includes a matrix material and hard ceramic particles uniformly distributed in the matrix material. The hard ceramic particles are uniformly dispersed at the blade, which can significantly improve the wear resistance of the blade, reduce the wear of the tool during use, and thus improve the long-term sharpness of the tool. In addition, the uniformly dispersed hard ceramic particles can form a micro-serrated structure at the blade, which improves the strength and cutting ability of the tool, makes the tool less likely to curl, and thus can improve the long-term sharpness of the tool. Description of the drawings Figure 1 is a schematic diagram schematically showing the structure of a tool according to an embodiment. Figure 2 is a partial enlarged view of Figure 1 according to an embodiment of the present application. Specific embodiments Now, the present invention will be described more fully in conjunction with exemplary embodiments hereinafter. However, the present invention may be implemented in a variety of different forms and should not be construed as being limited to the exemplary embodiments set forth herein. These embodiments are provided so that the disclosure of the present invention will be thorough and complete and the scope of the present invention will be fully conveyed to those skilled in the art. Hereinafter, a tool according to the present invention will be described in detail in conjunction with FIGS. 1 to 2. FIG. 1 is a schematic diagram schematically showing the structure of a tool according to an embodiment. FIG. 2 is a partial enlarged view of FIG. 1 according to an embodiment of the present application. Referring to FIG. 1 , a tool 100 according to an embodiment includes a main body 10 and a blade 20 coupled to the main body 10. For example, the main body 10 and the blade 20 may be formed integrally. According to an embodiment of the present disclosure, the main body 10 may include a matrix material or a composite material (the composite material is described later), or may be made of a matrix material or a composite material. For example, the main body 10 is composed of a matrix material or a composite material. The matrix material includes at least one of martensitic stainless steel, austenitic stainless steel, and duplex stainless steel. The melting point of the matrix material is typically in the range of 1300° C. to 1500° C. The blade 20 may include or be made of a composite material, for example, the blade 20 may consist of a composite material. The composite material may include a matrix material (as described above) and hard ceramic particles uniformly distributed in the matrix material, wherein the hard ceramic particles may include at least one of calcium carbide (WC, melting point 2870°C), silicon carbide (SiC, melting point 2700°C), zirconium oxide (ZrCh, melting point 2700°C), aluminum oxide (AI2O3, melting point 2054°C), _chromium carbide ( _Cr7C3 , melting point 1890°C), titanium oxide ( _TiO2 , melting point 3140°C), titanium carbide (TiC, melting point 3140°C) and silicon _nitride ( _Si3N4 , melting point 1900°C). The hard ceramic particles have a melting point higher than that of the matrix material. As shown in FIG2, the hard ceramic particles are uniformly dispersed at the blade 20, And the particle size of the hard ceramic particles can be 20|im-100|im, or 30|im-90|im, or 40|im-80|im, or 50|im-70|im. The hard ceramic particles have higher hardness and wear resistance than the matrix material. Therefore, the hard ceramic particles are evenly distributed in the matrix material, which can significantly enhance the wear resistance of the blade, so that the wear of the tool 100 during use is reduced. It should be noted that when the particle size of the hard ceramic particles is less than 20gm, the improvement of the wear resistance of the blade 20 may not be obvious; when the particle size of the hard ceramic particles is greater than 100pm, the combination effect of the hard ceramic particles and the matrix material is The result may be poor, which may affect the improvement of the wear resistance of the tool 100. The hard ceramic particles can have various regular or irregular shapes. The hard ceramic particles are evenly dispersed in the inner and outer surfaces of the blade 20, and the hard ceramic particles exposed on the outer surface of the blade 20 are in a state of micro-protrusions from the surface of the blade 20, so that a micro-serration structure can be formed on the surface of the blade, which improves the strength and cutting ability of the tool, making it less likely for the tool to roll, thereby further improving the long-term sharpness of the tool. The composite material included in the main body 10 and the composite material included in the blade 20 may include the same kind of hard ceramic particles (for example, both include TiC), or may include different kinds of hard ceramic particles. For example, the composite material included in the main body 10 includes TiC, and the composite material included in the blade 20 includes _Si3N4 _. In the composite material, the mass percentage of the matrix material may be 70%-90%, and the mass percentage of the hard ceramic particles may be 10%-30% _. If the mass percentage of the hard ceramic particles is less than 10%, it may be difficult to form a micro-serrated structure due to the sparse distribution of the hard ceramic particles, so that the wear resistance improvement effect is not obvious. If the mass percentage of the hard ceramic particles is greater than 30%, the toughness may be deteriorated due to excessive modification, so that the blade is easy to break. Next, the method for manufacturing the above-mentioned tool 100 will be described in detail. First, the matrix material powder and the hard ceramic particles are mixed evenly by a wet ball milling mixing process to prepare the composite material powder, specifically as follows: hard ceramic particles with a particle size of 20|im-100|im and the matrix material powder are mixed according to a ratio to obtain a mixture and loaded into a ball mill, wherein the matrix material powder input accounts for 70%-90% by mass, and the hard ceramic particle powder input accounts for 10%-30% by mass; grinding balls are added to the ball mill, and the grinding balls can be aluminum oxide balls with a diameter of 0.5mm; liquid grinding media such as alcohol are added to the ball mill, wherein the volume ratio of the mixture, the grinding balls, and the liquid grinding media can be 1:2:1; grinding, the grinding time can be 12h-20h, and the rotation speed can be 2000r/min; powder making, adding a surfactant and a defoaming agent to the composite material slurry obtained by grinding, mixing, placing in an ultrasonic mixer for mixing for 30min, and then drying by a spray powder making method, wherein, The weight of the surfactant is 0.5%-3% of the weight of the slurry, and the weight of the defoamer is 0.2%-1% of the weight of the slurry. The conditions of the spray powder method are as follows: the atomization pressure is 0.3-0.6MPa, preferably 0.4-0.5MPa; the atomization air flow rate is 0.5-5m3/h, preferably Selected as 1-3m3/h; inlet temperature is 200-600. Preferably 300-400. (2; the outlet temperature is 50-200°C, preferably 80-160°C _. Then, the tool embryo is prepared by powder metallurgy. The matrix material powder and the composite material powder are pressed in a mold by a pressing process to form an initial tool embryo. Specifically, a sufficient amount of composite material powder is placed in a position corresponding to the blade 20 in the mold, and a sufficient amount of matrix material powder is placed in a position corresponding to the main body 10 in the mold. The initial tool embryo is formed integrally under 200MPa-500MPa by a pressing process. In this case, the portion of the initial tool embryo corresponding to the blade of the tool is composed of the composite material, and the portion of the initial tool embryo corresponding to the main body of the tool is composed of the matrix material, but the present disclosure is not limited thereto. For example, the composite material powder can be added to the positions corresponding to the blade 20 and the main body 10 in the mold. The portion of the initial tool embryo corresponding to the main body 10 of the tool manufactured in this way is composed of the composite material. In other words, the initial tool embryo can be formed integrally of the composite material. The initial tool body is subjected to a solid phase sintering process in a protective atmosphere. The sintering temperature is generally 0.7 to 1.0 Tm (Tm is the absolute melting point), which can be 910°C-1500°C, and the sintering time can be 20min-40min, so as to prepare the tool body. In order to avoid the formation of an oxide layer that affects the properties of the tool during the sintering process, one of reducing gas, nitrogen or inert gas can be used as a protective gas or sintering can be performed in a vacuum environment to avoid direct contact between the powder in the initial tool body and oxidizing gases such as oxygen. During the sintering process, since the hard ceramic material has a higher melting point than the matrix material, the hard ceramic particles will always be in a solid state, while the matrix material powder will flow, diffuse, dissolve, and recrystallize with each other. In addition, along with the process of mutual flow, diffusion, dissolution, and recrystallization of the matrix material powder, the gas in the powder gap in the initial tool body or the gas dissolved in the metal can be completely driven out at high temperature, and the degree of densification is increased. Finally, After the tool blank is cooled, it is subjected to conventional grinding and sharpening. The above method for preparing the tool blank is only an example. Optionally, the main body 10 made of a matrix material or a composite material and the blade 20 made of a composite material can be manufactured by a press molding process or a powder metallurgy process, and then the blade 20 is welded (for example, cold welding) to the main body 10 to manufacture the tool 100. The tool 100 according to the present invention will be described in more detail below in conjunction with an embodiment, and the root The knife 100 of the present invention is evaluated for its long-lasting sharpness and blade strength. Example 1 Tie powder with a particle size of 50 gm and martensitic stainless steel powder with a particle size of 50 gm are ground for 15 hours using the above ball milling mixing process to prepare a composite material slurry, wherein the mass percentage of martensitic stainless steel powder is 80% and the mass percentage of TiC powder is 20%. The composite material powder is prepared by a spray powder making method, and the conditions of the spray powder making method are as follows: atomization pressure: 0.4 MPa, atomization air flow rate: 2 m ³ /h; inlet temperature: 300-400°C, outlet temperature: 120. (2. The composite material powder is integrally pressed into an initial tool embryo by a pressing molding process, and the molding pressure is 300 MPa _. The initial tool embryo is sintered in a vacuum environment, the sintering temperature is 1300°C, and the sintering time is 30 min to obtain a tool embryo. After the tool embryo is cooled, it is subjected to conventional grinding and sharpening to manufacture a tool 100. Example 2 Except that the mass percentage of martensitic stainless steel powder in the composite material powder is 90%, and the mass percentage of TiC powder is 10%, a tool 100 is manufactured in a method substantially the same as that of Example 1. Example 3 Except that the mass percentage of martensitic stainless steel powder in the composite material powder is 83.3%, and the mass percentage of TiC powder is 16.7%, a tool 100 is manufactured in a method substantially the same as that of Example 1. Example 4 Except that the mass percentage of martensitic stainless steel powder in the composite material powder is 70%, and the mass percentage of TiC powder is 30%, a tool 100 is manufactured in a method substantially the same as that of Example 1. Example 5 Except that the mass percentage of martensitic stainless steel powder in the composite material powder is 60%, The tool 100 was manufactured in the same manner as in Example 1 except that the mass percentage of the TiC powder was 40%.

A tool 100 was manufactured in substantially the same manner as in Example 1, except that the mass percentage of martensitic stainless steel powder in the composite material powder was 95% and the mass percentage of TiC powder was 5%. Example 7 A tool 100 was manufactured in substantially the same manner as in Example 1, except that TiC powder with a particle size of 10 gm and martensitic stainless steel powder with a particle size of 50 gm were used to prepare the composite material powder. Example 8 A tool 100 was manufactured in substantially the same manner as in Example 1, except that TiC powder with a particle size of 20 gm and martensitic stainless steel powder with a particle size of 50 gm were used to prepare the composite material powder. Example 9 A tool ₁₀₀ was manufactured in substantially the same manner as in Example 1, except that TiC powder with a particle size of 40 gm and martensitic stainless steel powder with a particle size of 50 gm were used to prepare the composite material powder. Example 10 A tool ₁₀₀ was manufactured in _{substantially} the same manner as in Example 1, except that Tie powder with a particle size of 60 gm and martensitic stainless steel powder with a particle size of 50 gm were used to prepare the composite material powder. Example 11 A tool ₁₀₀ was manufactured in substantially the same manner as in Example 1, except that Tie powder with a particle size of 80 gm and martensitic stainless steel powder with a particle size of 50 gm were used to prepare the composite material powder. A tool 100 was manufactured in the same manner as in Example 1 except that the composite material powder was prepared using TiC powder with a particle size of 100 μm and martensitic stainless steel powder with a particle size of 50 gm. Example 12 A tool 100 _was manufactured in the same manner as in Example 1 except that the composite material powder was prepared using TiC powder with a particle size of 100 μm and martensitic stainless steel powder with a particle size of 50 gm. Example 13 A tool 100 was manufactured in the same manner as in Example 1 except that the composite material powder was prepared using TiC powder with a particle size of 120 μm and martensitic stainless steel powder with a particle size of 50 gm. Except for preparing composite powder from powder, a tool 100 is manufactured in a method basically the same as in Example 1. Example 14: Except for preparing composite powder from SiC powder with a particle size of 50gm and martensitic stainless steel powder with a particle size of 50gm, a tool 100 is manufactured in a method basically the same as in Example 1. Example 15: Except for preparing composite powder from ZrCh powder with a particle size of 50gm and martensitic stainless steel powder with a particle size of 50gm, a tool 100 _is manufactured in a method basically the same as in Example 1. Example 16: Except for preparing composite powder from Al2O3 powder with a particle size of 50gm and martensitic stainless steel powder with a particle size of 50gm, a tool ₁₀₀ is manufactured in a method basically the same as in Example 1. Example 17: Except for preparing composite powder from Si3N4 powder with a particle size of 50gm and martensitic stainless steel powder with a particle size of 50gm, a tool 100 is manufactured in a method basically the same as in Example 1. Comparative Example 1: Ordinary martensitic tool. The evaluation method is:

(1) Durable sharpness test: Durable sharpness adopts the simulated tool life test method. The larger the value of the durable sharpness, the longer the durable sharpness life, and the smaller the value of the durable sharpness, the opposite. The specific method is as follows: The simulated tool life test method is as follows: The tested tool edge is fixed horizontally on the tool fixing device with the cutting edge downward, and after adding the silicon code, it is pressed on the simulation with a pressure of 16N. The cutting simulation (3mm kraft paper) remains stationary, and the tool fixing device is driven by the motor and air pressure to drive the tool to cut in the X-axis direction, with a reciprocating speed of 50mm/s, and at the same time, it rises in the Z-axis direction and moves 1mm in the Y-axis direction to shape the simulation. The cutting stroke is 100mm, and it ends after cutting the simulation 5 times. The evaluation object (ham sausage) is used. The knife's long-lasting sharpness is determined. The test is terminated when the object cannot be cut. The total number of cuts from the start to the end of the test is recorded, which is the knife's long-lasting sharpness. The more the total number of cuts, the higher the long-lasting sharpness.

(2) Blade strength test: Test the impact toughness of the blade. The reference standard is GBT 1817-1995. Specifically, by placing a pendulum of a certain mass at a certain height, allowing the pendulum to swing freely, observing the mass and height of the pendulum when the test object cracks, the impact toughness value is obtained through the calculation formula obtained in the standard. The greater the impact toughness value, the stronger the toughness and strength of the material, and generally speaking, the less likely it is to chip. The durable sharpness and blade strength of the cutters of Examples 1 to 17 and Comparative Example 1 were tested by using the above evaluation method, and the results of the tests are shown in Table 1 below. Table 1

As can be seen from Table 1, the knives of Example 1 to Example 13 all exhibit good lasting sharpness. Comparing the test results of the cutting tools of Example 1 and Example 5, it was found that although the durable sharpness of Example 5 was slightly improved, the high mass percentage of hard ceramic particles caused a significant decrease in the strength of the blade. . Normally, the impact toughness of the blade is required to be no less than 40 J/cm ³ _. Based on Example 4, it can be seen that the mass percentage of hard ceramic particles is preferably no more than 30%. Comparing the test results of the cutting tools of Example 1 and Example 6 with reference to Comparative Example 1, it is found that the mass percentage of hard ceramic particles in Example 6 is too low, resulting in a small improvement in the lasting sharpness. Combined with Example 2, it can be seen that the mass percentage of hard ceramic particles is preferably not less than 10% to significantly improve the lasting sharpness of the tool. That is to say, when the mass percentage of hard ceramic particles is in the range of 10%-30%, it has excellent long-lasting sharpness and blade strength properties. Comparing the test results of the cutting tools of Examples 1 to 6, it was found that the higher the mass percentage of the hard ceramic particles, the stronger the effect on improving the lasting sharpness of the cutting tool 100, confirming that the hard ceramic particles of the present invention can significantly Improves the long-lasting sharpness of your knives. Comparing the test results of the cutting tools of Example 1 and Example 7, it was found that the micro-serrated structure produced in Example 7 due to the too small particle size of the hard ceramic particles (less than 20 gm) did not improve its lasting sharpness. It is confirmed that the particle size of the hard ceramic particles is preferably greater than 20 pm in order to significantly enhance the lasting sharpness of the blade portion 20 . Comparing the test results of the cutting tools of Example 1 and Example 13, it was found that the durable sharpness of Example 13 was not improved well, and the strength of the blade was greatly reduced, confirming that the particle size of the hard ceramic particles is larger than Although the long-lasting sharpness can still be improved to a certain extent in the case of 100pm, its excessively large particle size will lead to a significant decrease in the strength of the blade. The test results of the cutting tools of Examples 8 to 12 are compared with Comparative Example 1. It can be found from Table 1 that as the particle size of the hard ceramic particles increases, the sharpness durability of the tools first increases and then decreases, but they all have good lasting sharpness (for example, the lasting sharpness is greater than 600). And still has excellent blade lightness (for example, greater than 40J/cm ³ )□ The test results of the cutting tools of Examples 14 to 17 are compared with Comparative Example 1. The change in the type of hard ceramic material has a slight impact on the lasting sharpness of the tool, and all have better lasting sharpness than the tool in Comparative Example 1. While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, those skilled in the art will understand that all modifications can be made without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents. Various changes in form and detail may be made here, depending on the circumstances. The embodiments should be considered in a descriptive sense only and not for purposes of limitation. Therefore, the scope of the invention is defined not by the specific embodiments of the invention but by the claims, and all differences within the scope will be construed as being included in the invention.

Claims

claims

1. A tool, characterized in that the tool comprises: a main body, made of a matrix material or a composite material; and a blade, made of the composite material and bonded to the main body, wherein the composite material comprises the matrix material and hard ceramic particles uniformly distributed in the matrix material, wherein the hard ceramic particles have a higher melting point than the matrix material.

2. The tool according to claim 1, wherein the base material includes at least one of martensitic stainless steel, austenitic stainless steel and duplex stainless steel.

3. The tool according to claim 1, characterized in that the hard ceramic particles include at least one of calcium carbide, silicon carbide, aluminum oxide, aluminum carbide, titanium oxide, titanium carbide and silicon nitride.

4. The tool according to claim 1, characterized in that the particle size of the hard ceramic particles is in the range of 20|im-100|im.

5. The tool according to claim 1, characterized in that, based on the total mass of the composite material, the mass percentage of the matrix material is 70%-90%, and the mass percentage of the hard ceramic particles is 10%-30 % _o

6. A method of manufacturing the tool according to any one of claims 1 to 5, characterized in that the method includes: uniformly mixing base material powder and hard ceramic particles through a ball milling mixing process. Composite material slurry is produced, and dry composite material powder is prepared by a spray powdering method; composite material powder is pressed in a mold to form a tool embryonic body or matrix material powder and composite material powder are pressed in a mold to form a tool embryonic body, wherein , the part of the tool embryo body corresponding to the blade of the tool is made of composite material, and the part of the tool embryo body corresponding to the main body of the tool is made of matrix material or composite material; the tool embryo body is sintered in a protective atmosphere , so that the matrix material melts and the hard ceramic particles remain in the particle state; and after cooling, the tool body is polished and sharpened.

7. The method according to claim 6, characterized in that, base material powder and The particle size of hard ceramic particles is in the range of 20|im-100|im.

8. The method according to claim 6, characterized in that the mass percentage of the matrix material powder in the composite material powder is 70%-90%, and the mass percentage of the hard ceramic particles is 10%-30% _.

9. The method according to claim 6, characterized in that the molding pressure when forming the tool embryo is 200MPa-500MPa.

10. A method of manufacturing the tool according to any one of claims 1 to 5, characterized in that the method includes: separately manufacturing the main body part and the blade part, and then combining the blade part to the main body part .