Household cutter with arc ion plating coating and edging method thereof

Abstract

The invention discloses a household cutter with an arc ion plating coating and an edging method of the household cutter, and relates to the technical field of household cutters. Hard coatings are deposited on the two sides of the cutting edge of the household cutter through arc ion plating, and part or all of the hard coatings on one side of the cutting edge are removed through grinding, so that single-side sharpening of the cutting edge of the household cutter subjected to film plating is achieved, the sharpness and the sharpness retentivity of the cutting edge of the household cutter subjected to arc ion film plating are improved, and the service life of the household cutter is prolonged. Meanwhile, by removing part or all of the sub-coatings, the physical properties of the two sides of the cutting edge can be different, and the cutting performance of the household cutter is improved.

Description

Technical Field

[0001] The invention relates to the technical field of household knives, and in particular to a household knife with an arc ion plating coating and a sharpening method thereof. Background Art

[0002] Household knives are usually used for cutting food, as opposed to industrial knives which are mainly used for cutting and removing metal. Therefore, higher requirements are placed on their sharpness. In order to reduce or eliminate the difficulty of re-sharpening household knives, arc ion plating can be used to coat the cutting edge with a metal hard film layer for surface strengthening, which can double the sharpness retention of the cutting edge.

[0003] However, due to the ion sheath effect during the arc ion plating process, a larger arc will form at the tip of the blade of the household knife after coating, and its initial sharpness will be lower than before coating. The reduction in the initial sharpness of the blade is an objective law of blade coating, which puts very high demands on the coating process. Maintaining the sharpness of the blade before coating has become the core issue of the arc ion plating process. Solving this problem is difficult and places very high demands on the coating equipment. Summary of the invention

[0004] The present invention provides a method for sharpening a household knife with an arc ion plating coating, wherein both sides of the cutting edge of the household knife are deposited with a hard coating by arc ion plating, and the method comprises the following steps:

[0005] A part or all of the hard coating on one side of the cutting edge is removed by grinding.

[0006] Optionally, the hard coating comprises a bonding layer, a transition layer and a functional layer deposited in sequence on the cutting edge substrate;

[0007] The functional layer and the transition layer are at least one of transition metal nitrides, transition metal carbonitrides and transition metal borides, or at least one of ternary or more multi-component nitrides or carbonitrides composed of transition metals and III A or IV A group elements;

[0008] The bonding layer is at least one of a transition metal, a transition metal nitride, and a transition metal boride, or an alloy of a transition metal and a III A or IV A group element, or a nitride of the alloy;

[0009] The transition group metal is at least one of Group IV B, Group VB and Group VI B elements.

[0010] Optionally, the method specifically comprises the following steps:

[0011] Grinding removes part or all of the functional layer on one side of the cutting edge.

[0012] Optionally, the method specifically comprises the following steps:

[0013] The functional layer and part or all of the transition layer on one side of the cutting edge are removed by grinding.

[0014] Optionally, the method specifically comprises the following steps:

[0015] The functional layer, transition layer and part or all of the bonding layer on one side of the cutting edge are removed by grinding.

[0016] Optionally, the method specifically comprises the following steps:

[0017] The hard coating on one side of the cutting edge and a portion of the cutting edge base are removed by grinding.

[0018] Optionally, the method specifically comprises the following steps:

[0019] Mount household knives on automatic sharpening machines;

[0020] According to the preset edge profiling curve, the edge of the household knife is ground on one side with a grinding wheel, the single-sided edge angle range is 0-20°, the grinding amount of the grinding wheel is 0.00001-0.002mm, the idle running speed of the grinding wheel is 6000-9000 rpm, the X-axis grinding buffer speed is 10-50mm / min, the Y-axis sampling speed is greater than 1000mm / min, and the Z-axis magnification ratio is 1-5 times.

[0021] Based on the above-mentioned method for sharpening a household knife with an arc ion plating coating, the present invention proposes a household knife, on both sides of which a hard coating is deposited by arc ion plating, and the hard coating on one side of the cutting edge is completely or partially removed by the above-mentioned method for sharpening a household knife with an arc ion plating coating.

[0022] Optionally, the hard coating comprises a bonding layer, a transition layer and a functional layer deposited in sequence on the cutting edge substrate;

[0023] The functional layer and the transition layer are at least one of transition metal element nitrides, transition metal element carbonitrides and transition metal element borides, or at least one of ternary or more multi-element nitrides or carbonitrides composed of transition metal elements and III A or IV A group elements;

[0024] The bonding layer is at least one of a transition metal, a transition metal nitride, and a transition metal boride, or an alloy of a transition metal and a III A or IV A group element, or a nitride of the alloy;

[0025] The transition metal element is at least one of Group IV B, Group VB and Group VI B elements.

[0026] Optionally, the functional layer on one side of the cutting edge is completely or partially removed by grinding;

[0027] Alternatively, the functional layer and part or all of the transition layer on one side of the cutting edge are removed by grinding;

[0028] Alternatively, the functional layer, transition layer and part or all of the bonding layer on one side of the cutting edge are removed by grinding;

[0029] Alternatively, the hard coating on one side of the cutting edge and a portion of the cutting edge base are removed by grinding.

[0030] The present invention has the following beneficial effects:

[0031] The present invention is based on the arc ion plating of the blade of household knives. Through subsequent processing steps, one side of the blade is further finely sharpened, so that the sharpness and sharpness retention of the blade of the household knives after arc ion plating are improved. At the same time, by removing part or all of the sub-coating, the physical properties on both sides of the blade can be differentiated to improve the cutting performance of the household knives. The process is simple and easy to implement, and the requirements for coating equipment and coating process are reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0033] Figure 1 Schematic diagram of the cutting edge cross section of household knives after arc ion plating in some embodiments of the present invention;

[0034] Figure 2 Schematic diagram of the cutting edge cross section of a coated household knife after single-side sharpening in some embodiments of the present invention;

[0035] Figure 3 It is a schematic structural diagram of an automatic sharpening machine used in the method for sharpening a household knife with an arc ion plating coating according to the present invention;

[0036] Figure 4 The cutting test data of the coated household knives before single-side sharpening in some embodiments of the present invention;

[0037] Figure 5 These are the cutting test data of the coated household knives after single-side sharpening in some embodiments of the present invention.

[0038] Description of reference numerals:

[0039] 1. Cutting edge base; 2. Bonding layer; 3. Transition layer; 4. Functional layer. DETAILED DESCRIPTION

[0040] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] Household knives are usually used for cutting food, which is different from industrial knives which are mainly used for cutting and removing metal. Therefore, higher requirements are placed on their sharpness. In order to reduce or eliminate the difficulty of re-sharpening household knives, the edge surface can be strengthened to improve the retention of its sharpness. Commonly used methods include carburizing, nitriding, ion plating, laser cladding and thermal cladding at the edge.

[0042] Carburizing and nitriding of the cutting edge of household knives are mostly completed during the heat treatment of the blank in the previous step of the production process. This process does not affect the normal sharpening of the cutting edge, but the processing cost is high and the improvement of the cutting edge sharpness is limited.

[0043] Laser cladding is a type of hot cladding. The most commonly used method of hot cladding is to clad carbide powder on one side of the cutting edge of a household knife, heat and melt the carbide powder on one side of the cutting edge, and then sharpen both sides to obtain a cutting edge with good sharpness. This process ultimately retains a carbide hardened layer on one side of the cutting edge to improve the sharpness retention of the cutting edge. However, due to the large material difference between the hot-clad alloy hardened layer and the tool substrate, the hardness difference is also too large, the internal stress between the alloy hardened layer and the tool substrate is relatively large, and the hot-clad alloy hardened layer is a cast structure of a powder alloy, with a large porosity and poor tissue density, which ultimately leads to limited improvement in the sharpness retention of the hot-clad household knife cutting edge.

[0044] In arc ion plating, ions bombard the tool surface with high energy, forming a strong bond between the coating and the tool substrate. This strong bonding force ensures that the coating is not easy to fall off during the use of the tool, and can stably exert its performance advantages for a long time. Even when the tool is subjected to large cutting and impact forces, the coating can remain intact, providing continuous protection and performance improvement for the tool; and arc ion plating technology can achieve uniform coating on tool edges of complex shapes; through reasonable design of coating equipment and process parameters, it can ensure that the coating has consistent thickness and performance in all parts of the tool edge, avoiding tool performance differences caused by local uneven coating.

[0045] After intensive research, the inventors of the present application discovered that due to the ion sheath effect in the arc ion plating process, a larger arc will form at the tip of the cutting edge of household knives after coating, and their initial sharpness will be lower than that before coating; the reduction in the initial sharpness of the cutting edge is an objective law, which puts very high demands on the coating process. Maintaining the sharpness of the cutting edge before coating has become the core of the process, which is difficult and cannot be achieved by ordinary coating equipment.

[0046] Therefore, the present invention proposes a method for sharpening household knives with arc ion plating coatings. On the basis of arc ion plating of the blade of the household knife, the blade is further finely sharpened on one side through further subsequent processing steps and the cooperation of the previous coating process. The initial sharpness of the blade of the coated household knife that has been sharpened on one side can be further improved, and the sharpness retention of the blade is also further improved. The method is simple and efficient, and avoids the problems of increased cost and complex process caused by high requirements for coating equipment.

[0047] In the embodiment of the present invention, the household knife edge can be made of a stainless steel substrate that has been quenched and strengthened. The edge is sharpened on a dedicated automatic edge sharpening machine (see EN ISO 8442-5 2005, the household knife standard). Figure 3 ) is a substrate that has been finely sharpened for multiple times; the stainless steel substrate has been subjected to arc ion plating edge strengthening treatment, and a hard coating is deposited on the edge substrate.

[0048] In some embodiments, the pre-processing of household knives specifically includes the following steps:

[0049] The stainless steel sheets are stamped into knife blanks, which are then quenched and tempered to achieve the hardness and strength required for use as a base for household knives.

[0050] The surface of the knife blank is then water-ground and grinded with a grinding wheel, and then the cutting edge is further sharpened; the process of sharpening the cutting edge includes two or more passes of fine grinding and edge polishing from coarse to fine, so that the cutting edge meets the standard requirements for cutting food, and the requirement standard is EN ISO 8442-5 2005. In order to further carry out arc ion plating, higher requirements can be put forward on the quality of the base cutting edge, that is, to reach the excellent level under this inspection standard.

[0051] Based on the above pre-processing steps of household knives, in some embodiments, arc ion plating of household knives specifically includes the following steps:

[0052] The household knives that meet the requirements and are ready for coating will be cleaned after the residual magnetism from grinding, and placed in a special ultrasonic cleaning line for multiple cleanings to remove the wax and physically adsorbed impurities on the surface, balance the pH value of the surface, dry the moisture adsorbed on the surface, and hang them on a special rotating rack ready for furnace coating.

[0053] Push the rotating rack into the coating machine cavity, evacuate and heat to the specified temperature, and complete all the coating processes of household knives according to the specific coating process. The cutting edge cross section of the household knives after coating is shown in the table below. Figure 1 .

[0054] In an embodiment of the present invention, a method for sharpening a household knife having an arc ion plating coating comprises the following steps:

[0055] A part or all of the hard coating on one side of the cutting edge is removed by grinding, wherein the cutting edge cross section after all the hard coating on one side of the cutting edge is removed by grinding is referred to as Figure 2 .

[0056] In some embodiments, the step specifically includes:

[0057] Protect the surface of household knives that do not need to be sharpened after arc ion coating, and then install them on a special automatic sharpening machine. The structure of the automatic sharpening machine can be found in Figure 3 .

[0058] Call out the edge profiling curve that has been determined during the front sharpening process of the household knife, adjust the single-side sharpening angle to a certain value between 0-20°, and use a resin diamond grinding wheel or cubic boron nitride grinding wheel with a particle size of more than 1000 mesh to perform single-side sharpening on the edge of the coated household knife.

[0059] The idling speed of the grinding wheel is adjusted to a certain value between 6000 and 9000 rpm, the grinding amount of the grinding wheel is adjusted to a certain value between 0.00001 and 0.00200 mm, the X-axis grinding buffer speed is controlled to a certain value between 10 and 50 mm / min, the Y-axis sampling speed is controlled to be above 1000 mm / min, the Z-axis magnification ratio is controlled to a certain value between 1 and 5 times, and the cutting edge of the household knife after arc ion plating is ground once or several times at the same angle or with gradually increasing angles on one side, so as to achieve secondary single-sided re-sharpening of the coated household knife.

[0060] In addition, the tip of the cutting edge is manually ground with a fine cloth wheel or a leather wheel so that the entire curve of the cutting edge is complete and free of microscopic defects.

[0061] Furthermore, the present invention also conducts a cutting performance test on the household knives with arc ion plating coating prepared in the above embodiment, and the performance test is conducted with reference to the European Union EN ISO 8442-5 2005 standard.

[0062] The working principle of the testing machine is to use a fixed household knife to cut a uniform standard object instead of test paper under the premise of standard cutting force, standard cutting speed and standard cutting test distance, and the accumulation of the thickness of the cut test paper represents the corresponding tool sharpness performance.

[0063] Cutting test data of coated household knives before single-side sharpening Figure 4 , the cutting test data of coated household knives after single-side sharpening can be found in Figure 5 .

[0064] The test results were compared with the test results of similar household knives that had not been sharpened on one side after arc ion plating. It was concluded that the sum of the first three cutting test data of the household knives after coating represents their initial sharpness (ICP), which is 72.4mm, and the sum of the 60 cutting test values ​​represents the sharpness retention (TCC), which is 1344.1mm; while the same knives that were sharpened on one side after coating had an initial sharpness (ICP) of 136.7mm and a sharpness retention (TCC) of 1975.1mm. By comparison, it can be concluded that for household knives after arc ion plating, correct single-side re-sharpening and control of correct process parameters can further improve the initial sharpness and sharpness retention of household knives.

[0065] Therefore, it can be seen from the above embodiments that the present invention will finely grind the edge of the household knife after arc ion plating again, and grind one side of the edge with a slight force. Under the premise of not destroying the integrity of the cutting edge line at the tip of the cutting edge, the coating surface of one side of the cutting edge is repaired, thereby improving the flatness of the cutting edge, reducing the cutting edge arc radius, sharpening the initial sharpness of the cutting edge, and further improving the sharpness retention of the cutting edge after coating. The production process is simple and easy to implement.

[0066] Further, based on the above-mentioned embodiment of the method for sharpening a household knife having an arc ion plating coating, in some specific embodiments, refer to Figure 1 The hard coating includes a bonding layer 2, a transition layer 3 and a functional layer 4 deposited in sequence on a cutting edge substrate 1.

[0067] The functional layer and the transition layer are at least one of transition metal nitrides, transition metal carbonitrides and transition metal borides, or at least one of ternary or more multi-component nitrides or carbonitrides composed of transition metals and III A or IV A elements; the bonding layer is at least one of transition metals, transition metal nitrides and transition metal borides, or an alloy composed of transition metals and III A or IV A elements, or a nitride of the alloy;

[0068] The transition metal is at least one of group IV B, group VB and group VI B elements, such as Ti, Zr, Hf, V, Nb, Ta, Cr, Mo and W.

[0069] The functional layer and transition layer can be made of transition metal nitrides such as TiN and CrN, or transition metal carbonitrides such as TiCN and CrCN, or transition metal borides such as TiB2 and HfB2, or ternary nitrides (such as TiAlN, CrAlN, TiSiN, etc.) or carbonitrides (such as TiAlCN, CrAlCN, TiSiCN, etc.) composed of individual elements of group III A or group IV A (Al, Si, B, etc.), or ternary nitrides (such as TiAlN, CrAlN, TiSiN, etc.) or carbonitrides (such as TiAlCN, CrAlCN, TiSiCN, etc.) composed of individual elements of group III A or group IV A. Quaternary nitrides (such as TiAlBN, TiAlSiN, CrAlBN, CrAlSiN, etc.) or carbonitrides (such as TiAlBCN, TiAlSiCN, CrAlBCN, CrAlSiCN, etc.) composed of individual elements of Group A (Al, Si, B, etc.) and multi-component nitrides (such as TiCrAlBN, TiCrAlSiN, TiAlSiWN, TiAlSiVN, CrAlSiWN, CrAlBWN, etc.) or carbonitrides (such as TiCrAlBCN, TiCrAlSiCN, TiAlSiWCN, TiAlSiVCN, CrAlSiWCN, CrAlBWCN, etc.).

[0070] The bonding layer can be made of transition metals such as Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W or their nitrides (such as TiN, CrN, etc.), or alloys (such as TiAl, AlCr) composed of transition metals and individual elements in group III A or group IV A (such as Al, Si, B, etc.) and their nitrides (such as TiAlN, CrAlN, etc.) and borides (such as TiB2, etc.).

[0071] In these embodiments, in order to form a difference in physical properties between the two sides of the cutting edge to improve the cutting performance of the household knife, the hard coating on one side of the cutting edge can be completely or partially removed by grinding.

[0072] Based on this, in some embodiments, a complete functional layer is retained on one side of the blade of a household knife, and this side has good wear resistance and can keep the blade sharp for a long time; the functional layer is completely removed on the other side of the blade, and only the transition layer and the bonding layer are retained, or the functional layer and the transition layer are completely removed and only the bonding layer is retained, or the hard coating is completely removed to expose the base of the blade; for ordinary kitchen knives, during the cutting process, the side with the functional layer retained is used to efficiently cut vegetable or meat fibers, and the side with the functional layer removed has a lower surface hardness, so when cutting some easy-to-scatter ingredients, such as tofu, this side can better fit the ingredients and reduce the breakage of ingredients; for household knives such as bone chopping knives that have high requirements for strength and toughness, one side retains a functional layer with extremely high hardness to keep the blade from curling, and the side with the functional layer removed can keep the blade from breaking by virtue of its relatively low hardness and certain toughness.

[0073] In some other embodiments, in addition to having high hardness and wear resistance, the functional layer also has a certain hydrophobicity; the functional layer is retained intact on one side of the blade of the household knife, which can cut quickly when cutting food, prevent food from sticking, and the cut slices are easier to separate; the hydrophobic functional layer is removed from the other side of the blade, which has better hydrophilicity, can absorb food with moisture, avoid juice splashing, and avoid slipping during cutting; therefore, the surface hydrophilicity and hydrophobicity of the household knife on both sides of the blade that contact the food can be changed by removing the functional layer on one side of the blade, thereby improving the sharpness retention of the blade while improving the comfort of cutting food.

[0074] In some other embodiments, one side of the cutting edge of the household knife retains a functional layer with high hardness and wear resistance, while the other side is completely removed from all hard coatings to expose the cutting edge base (see Figure 2 ), after household knives become blunt after long-term use, the sharpness of household knives can be maintained by grinding the side without hard coating.

[0075] It should be noted that, based on the actually selected functional layer, transition layer and bonding layer materials and the specific requirements for physical properties such as hardness, wear resistance, hydrophilicity and hydrophobicity on both sides of the cutting edge in actual application scenarios, the functional layer, transition layer and bonding layer on one side of the cutting edge can be selectively removed, and the removal thickness and grinding angle can be specifically designed to meet these requirements.

[0076] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for sharpening a household knife with an arc ion plating coating, wherein both sides of the cutting edge of the household knife are deposited with a hard coating by arc ion plating, characterized in that: The method comprises the following steps: A part or all of the hard coating on one side of the cutting edge is removed by grinding.

2. The method for sharpening a household knife having an arc ion plating coating according to claim 1, characterized in that: The hard coating comprises a bonding layer, a transition layer and a functional layer deposited in sequence on the cutting edge substrate; The functional layer and the transition layer are at least one of transition metal nitrides, transition metal carbonitrides and transition metal borides, or at least one of ternary or more multi-component nitrides or carbonitrides composed of transition metals and III A or IV A group elements; The bonding layer is at least one of a transition metal, a transition metal nitride, and a transition metal boride, or an alloy of a transition metal and a III A or IV A group element, or a nitride of the alloy; The transition group metal is at least one of Group IV B, Group VB and Group VI B elements.

3. The method for sharpening a household knife having an arc ion plating coating according to claim 2, characterized in that: The specific steps include: Grinding removes part or all of the functional layer on one side of the cutting edge.

4. The method for sharpening a household knife having an arc ion plating coating according to claim 2, characterized in that: The specific steps include: The functional layer and part or all of the transition layer on one side of the cutting edge are removed by grinding.

5. The method for sharpening a household knife having an arc ion plating coating according to claim 2, characterized in that: The specific steps include: The functional layer, transition layer and part or all of the bonding layer on one side of the cutting edge are removed by grinding.

6. The method for sharpening a household knife having an arc ion plating coating according to claim 2, characterized in that: The specific steps include: The hard coating on one side of the cutting edge and a portion of the cutting edge base are removed by grinding.

7. The method for sharpening a household knife having an arc ion plating coating according to claim 1, characterized in that: The specific steps include: Mount household knives on automatic sharpening machines; According to the preset edge profiling curve, the edge of the household knife is ground on one side with a grinding wheel, the single-sided edge angle range is 0-20°, the grinding amount of the grinding wheel is 0.00001-0.002mm, the idle running speed of the grinding wheel is 6000-9000 rpm, the X-axis grinding buffer speed is 10-50mm / min, the Y-axis sampling speed is greater than 1000mm / min, and the Z-axis magnification ratio is 1-5 times.

8. A household knife having a hard coating deposited on both sides of its cutting edge by arc ion plating, characterized in that: The hard coating on one side of the cutting edge is completely or partially removed by the sharpening method for household knives with arc ion plating coating according to any one of claims 1 to 7.

9. The household knife according to claim 8, characterized in that: The hard coating comprises a bonding layer, a transition layer and a functional layer deposited in sequence on the cutting edge substrate; The functional layer and the transition layer are at least one of transition metal element nitrides, transition metal element carbonitrides and transition metal element borides, or at least one of ternary or more multi-element nitrides or carbonitrides composed of transition metal elements and III A or IV A group elements; The bonding layer is at least one of a transition metal, a transition metal nitride, and a transition metal boride, or an alloy of a transition metal and a III A or IV A group element, or a nitride of the alloy; The transition metal element is at least one of Group IV B, Group VB and Group VI B elements.

10. The household knife according to claim 9, characterized in that: The functional layer on one side of the cutting edge is completely or partially removed by grinding; Alternatively, the functional layer and part or all of the transition layer on one side of the cutting edge are removed by grinding; Alternatively, the functional layer, transition layer and part or all of the bonding layer on one side of the cutting edge are removed by grinding; Alternatively, the hard coating on one side of the cutting edge and a portion of the cutting edge base are removed by grinding.

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