JP5490158B2 - Surface coating material and cutting tool and machine tool using the same - Google Patents

Description

  The present invention relates to a surface coating material, a cutting tool using the same, and a machine tool.

  In recent years, due to the influence on the environment, so-called dry cutting methods that do not use a cutting fluid when cutting with a machine tool have begun to be used. This dry cutting method is provided with a TiN-based, TiAlN-based, or AlCrN-based metal nitride layer having a low coefficient of friction (about 0.4) and high heat resistance (about 500-1200 ° C.) on the surface. This is a technology that eliminates the need for a cutting fluid by mounting a cutting tool on a machine tool for cutting.

Japanese Patent Laid-Open No. 10-025566 Japanese Patent Laid-Open No. 2003-321764 JP 2007-131927 A JP 2007-283479 A

By the way, in the cutting tool used in the above-described dry cutting method, if it is intended to be used in a further high temperature region exceeding 1200 ° C., the metal nitride reacts with oxygen and oxidizes, so that volume expansion occurs. There has been a problem of cracks and the like. For this reason, for example, by providing a metal oxide layer made of low oxygen-permeable aluminum oxide (Al ₂ O ₃ ) on the surface of the metal nitride, it may be possible to use in a higher temperature region. ing.

  However, since the metal oxide layer made of aluminum oxide tends to have long and narrow crystal grains (aspect ratio: more than 5), it is missing from the surface of the cutting tool when it comes into contact with the workpiece, and the missing Peeling and defects due to welding starting from the location are likely to occur, resulting in difficulty in durability.

  Such a problem is not limited to the cutting tool used in the machine tool as described above, but if it is a surface coating material that requires high impact resistance while suppressing oxidation deterioration in a high temperature region, It can happen as well.

  In view of the above, an object of the present invention is to provide a surface coating material that can exhibit high impact resistance while suppressing oxidative deterioration in a high temperature region, and a cutting tool and a machine tool using the surface coating material.

The surface coating material according to the first aspect of the present invention for solving the above-mentioned problem comprises an oxide of aluminum and at least one of tin and zirconium and at least one of lithium, magnesium and silicon containing lithium. It has a metal oxide layer on its surface.

A surface coating material according to a second aspect of the present invention is the surface coating material according to the first aspect, wherein the metal oxide layer contains at least one oxide of tin and zirconium in a total amount of 0.1 to 15% by weight, lithium, magnesium , Characterized in that it contains a total of 0.1 to 15% by weight of one or more oxides containing at least lithium in silicon, and the balance is made of an oxide of aluminum.

  A surface coating material according to a third invention is characterized in that, in the first or second invention, the aspect ratio of the crystal grains of the metal oxide layer is 5 or less.

  A surface coating material according to a fourth invention is characterized in that, in any one of the first to third inventions, the metal oxide layer is provided on the surface of the metal nitride.

  The surface coating material according to a fifth aspect of the present invention is characterized in that, in the fourth aspect, the metal nitride is made of at least one nitride of aluminum, zirconium, chromium, silicon, and titanium.

  A surface covering material according to a sixth invention is characterized in that, in the fourth or fifth invention, the metal nitride is provided on the surface of the substrate.

  The surface coating material according to a seventh aspect is characterized in that, in the sixth aspect, the base material is made of high-speed tool steel or cemented carbide.

  Further, a cutting tool according to an eighth invention for solving the above-described problems is characterized by comprising the surface coating material according to any one of the first to seventh inventions.

  A machine tool according to a ninth invention for solving the above-mentioned problem is characterized by including a cutting tool made of the surface coating material according to any one of the first to seventh inventions. To do.

  According to the surface coating material according to the present invention, since the metal oxide layer becomes a crystal grain having a small aspect ratio, the metal oxide layer can suppress oxygen permeation into the interior, and at the same time, an impact is applied. Can be remarkably suppressed, and the durability can be greatly improved.

It is structure explanatory drawing of 1st embodiment of the surface coating material which concerns on this invention. It is a schematic block diagram of the manufacturing apparatus of the surface coating material of FIG. It is a phase diagram of an aluminum oxide-tin oxide system. It is a phase diagram of an aluminum oxide-zirconium oxide system. It is structure explanatory drawing of 2nd embodiment of the surface coating material which concerns on this invention.

  Embodiments of a surface coating material, a cutting tool using the surface coating material, and a machine tool according to the present invention will be described below with reference to the drawings, but the present invention is not limited to only the embodiments described below.

[First embodiment]
1st Embodiment of the surface coating material which concerns on this invention, the cutting tool using this, and a machine tool is described based on FIGS. FIG. 1 is an explanatory view of the structure of a surface coating material, FIG. 2 is a schematic configuration diagram of a production apparatus for the surface coating material, FIG. 3 is a phase diagram of an aluminum oxide-tin oxide system, and FIG. It is a state diagram of the system.

  As shown in FIG. 1, a surface coating material 10 according to this embodiment includes a base material 11 made of high-speed tool steel or cemented carbide, and aluminum (Al), zirconium (Zr) provided on the surface of the base material 11. ), Chromium (Cr), silicon (Si), titanium (Ti), a metal nitride layer 12 made of at least one nitride (N), and tin (Sn) provided on the surface of the metal nitride layer 12. ) And zirconium (Zr) and a metal oxide layer 13 made of an oxide (O) of aluminum (Al).

  Such a surface coating material 10 is formed by applying the metal nitride layer 12 made of the above-described composition to the base material 11 by a physical vapor deposition method (PVD) such as a sputtering vapor deposition method or an ion plating method. In addition, the metal oxide layer 13 can be provided in order and can be manufactured easily.

  Specifically, for example, the surface coating material 10 can be manufactured by using an apparatus (arc ion plating apparatus) as shown in FIG.

  As shown in FIG. 2, a table-like holder 102 that supports the base material 11 is disposed below the inside of the casing 101 that is airtight and airtight. The holder 102 is supported on the upper end of a rotating shaft 103 that is rotatably supported with respect to the casing 101. A motor 104 is connected to the lower end of the rotating shaft 103. On the other hand, a target 100 of various raw materials is disposed above the inside of the casing 101.

  The target 100 is connected to the + side of the DC power source 105, and the holder 102 is connected to the − side of the DC power source 105. A vacuum pump 106, an argon gas supply source 107, a nitrogen gas supply source 108, and an oxygen gas supply source 109 are connected to the casing 101 via control valves 106a to 109a, respectively.

  In such an apparatus, first, the base material 11 made of high-speed tool steel or cemented carbide is placed on the holder 102, and aluminum (Al), zirconium (Zr), chromium (Cr), silicon (Si) ), And a target 100 containing at least one of titanium (Ti). Next, by operating the vacuum pump 106 and opening the control valves 106a and 107a, argon gas (Ar) is supplied into the casing 101 while evacuating the inside of the casing 101. Argon atmosphere.

Subsequently, when the motor 104 is operated to rotate the holder 102 and the control valves 106a and 107a are closed, a DC voltage is applied between the target 100 and the holder 102 by the DC power source 105, whereby the target 100 and the holder 102 are rotated. An argon plasma is generated between the casing 101 and the inside of the casing 101 to raise the temperature. When the inside of the casing 101 reaches a predetermined temperature, the control valve 108a is opened, and nitrogen gas (N ₂ ) is supplied from the nitrogen gas supply source 108 to the inside of the casing 101 to cause arc discharge. The metal nitride layer 12 is formed on the surface of 11.

When the metal nitride layer 12 is formed on the base material 11 with a predetermined thickness, the control valve 108a is closed and the control valve 109a is opened to move the oxygen gas supply source 109 into the casing 101. By supplying oxygen gas (O ₂ ) and switching the target 100 to a target 100 containing at least one of tin (Sn) and zirconium (Zr) and aluminum (Al), the metal nitride layer 12 is formed. The metal oxide layer 13 is formed on the surface. Thereby, the said surface coating material 10 which consists of a composition as mentioned above can be manufactured easily.

In such a surface coating material 10, as can be seen from FIGS. 3 and 4, tin oxide (SnO ₂ ), zirconium oxide (ZrO ₂ ), and aluminum oxide (Al ₂ O ₃ ) are not dissolved at all. Since crystal grains of oxides of tin, zirconium and aluminum interfere with each other, the aspect ratio of the crystal grains of the metal oxide layer 13 is reduced (5 or less).

  For this reason, in the surface coating material 10, the metal oxide layer 13 can suppress oxygen permeation into the inside, and at the same time, can be remarkably suppressed from being lost even when an impact is applied. , Durability can be greatly improved.

  Therefore, when the surface coating material 10 is mounted on a machine tool using a cutting tool and dry cutting is performed, when the cutting tool comes into contact with a workpiece, the metal is removed from the surface of the cutting tool. Since the loss of the oxide layer 13 can be remarkably suppressed, it is possible to prevent the metal oxide layer 13 from being peeled off by the welding starting from the missing portion, the occurrence of defects, and the like. The durability of the oxide layer 13 can be greatly improved.

  Therefore, in the cutting tool and machine tool for the dry cutting method using the surface coating material 10, the volume expansion due to the oxidation of the metal nitride layer 12 even when used in a further high temperature region exceeding 1200 ° C. It is possible to prevent the occurrence of cracks and the like associated with a long-term, and the durability can be greatly improved.

  The metal oxide layer 13 preferably has a total content of at least one oxide of tin and zirconium of 0.1 to 15% by weight (particularly 0.1 to 1.5% by weight). This is because when the total content of at least one oxide of tin and zirconium exceeds 15% by weight, an amorphous phase is likely to be formed and the hardness tends to be low, which is not preferable. If the total content of one oxide is less than 0.1% by weight, the aspect ratio tends to exceed 5, which is not preferable.

  In addition, the cutting tool is not particularly limited as long as it is a tool for cutting, but it is very suitable if it is a gear cutting tool such as a hob or pinion cutter, or a broach, The machine tool is not particularly limited as long as it is capable of cutting, but a gear cutter such as a hobbing machine or a gear shaper or a broaching machine is very suitable. is there.

[Second Embodiment]
A second embodiment of the surface coating material and the cutting tool and machine tool using the same according to the present invention will be described with reference to FIG. FIG. 5 is an explanatory diagram of the structure of the surface coating material. In addition, about the part similar to the case of 1st embodiment mentioned above, by using the code | symbol similar to the code | symbol used in description of 1st embodiment mentioned above, 1st embodiment mentioned above is used. The description overlapping with the description in is omitted.

  As shown in FIG. 5, the surface coating material 20 according to the present embodiment is provided on the surface of the substrate 11, the metal nitride layer 12, and the metal nitride layer 12, and includes tin (Sn) and zirconium (Zr). And at least one of lithium (Li), magnesium (Mg), and silicon (Si) and a metal oxide layer 23 made of an oxide of aluminum (Al).

  Such a surface coating material 20 is applied to the substrate 11 by physical vapor deposition (PVD) such as sputter vapor deposition or ion plating as in the case of the first embodiment described above. Thus, the metal nitride layer 12 and the metal oxide layer 23 made of the above-described composition can be provided in order and can be easily manufactured.

  In the surface coating material 20 as described above, as described in the first embodiment, the aspect ratio of the crystal grains of the metal oxide layer 23 is small (5 or less), and aluminum, lithium, Magnesium and silicon have different valences, and oxides thereof are likely to be in solid solution with each other. Therefore, it is possible to improve the adhesion of the metal oxide layer 23 and reduce the friction coefficient.

  For this reason, in the surface coating material 20, as in the case of the first embodiment described above, the metal oxide layer 23 can suppress oxygen permeation to the inside and at the same time an impact is applied. However, it is possible to remarkably suppress the loss of the metal nitride layer 12 as well as to further reliably prevent the metal nitride layer 12 from being peeled off, so that the durability can be further improved.

  Therefore, in this embodiment, the same effect as in the case of the first embodiment described above can be obtained, and the durability can be further improved as compared with the case of the first embodiment described above. it can.

  Further, when the metal oxide layer 23 contains an oxide of lithium, the friction coefficient of the surface can be lowered. Therefore, when the metal oxide layer 23 contains at least a lithium oxide of lithium, magnesium, and silicon, More preferred.

  The metal oxide layer 23 has a total content of at least one of tin and zirconium of 0.1 to 15% by weight (particularly 0.1 to 1.5% by weight), and is composed of lithium, magnesium, The total content of at least one oxide of silicon is preferably 0.1 to 15% by weight (particularly 0.1 to 1.5% by weight). This is because if the total content of at least one oxide of lithium, magnesium and silicon exceeds 15% by weight, the hardness tends to be low, which is not preferable, and at least of lithium, magnesium and silicon. This is because if the total content of one kind of oxide is less than 0.1% by weight, it is difficult to improve adhesion and lower the friction coefficient, which is not preferable.

[Other Embodiments]
In the above-described embodiment, the case of the surface coating materials 10 and 20 in which the metal oxide layers 13 and 23 are provided on the metal nitride layer 12 on the substrate 11 has been described. It is also possible to omit 12 and provide a metal oxide layer directly on the substrate 11.

  In the above-described embodiment, the case of the surface coating materials 10 and 20 to which the base material 11 made of high-speed tool steel or cemented carbide is applied has been described. However, other metal materials (for example, various special steels and It is also possible to apply a base material made of alloy steel or the like.

  Since the surface coating material and the cutting tool and machine tool using the same according to the present invention can greatly improve durability, they can be used extremely beneficially in various industries such as machining. .

DESCRIPTION OF SYMBOLS 10 Surface coating material 11 Base material 12 Metal nitride layer 13 Metal oxide layer 20 Surface coating material 23 Metal oxide layer 100 Target 101 Casing 102 Holder 103 Rotating shaft 104 Motor 106 Vacuum pump 106a Control valve 107 Argon gas supply source 107a Control Valve 108 Nitrogen gas supply source 108a Control valve 109 Oxygen gas supply source 109a Control valve

Claims (9)

A surface coating material comprising a metal oxide layer formed of an oxide of at least one of tin and zirconium and at least one of lithium, magnesium, and silicon containing at least lithium and aluminum. The surface covering material according to claim 1,
The metal oxide layer is
Containing a total of 0.1 to 15% by weight of at least one oxide of tin and zirconium,
A total of 0.1 to 15% by weight of one or more oxides containing at least lithium among lithium, magnesium and silicon,
A surface coating material characterized in that the balance is made of aluminum oxide. The surface coating material according to claim 1 or 2,
The aspect ratio of crystal grains of the metal oxide layer is 5 or less. In the surface coating material according to any one of claims 1 to 3,
The surface coating material, wherein the metal oxide layer is provided on the surface of the metal nitride. The surface coating material according to claim 4,
The surface coating material, wherein the metal nitride is made of at least one nitride of aluminum, zirconium, chromium, silicon, and titanium. In the surface coating material according to claim 4 or 5,
The surface coating material, wherein the metal nitride is provided on a surface of a base material. The surface covering material according to claim 6,
The substrate is made of high-speed tool steel or cemented carbide. It consists of the surface coating material as described in any one of Claims 1-7. The cutting tool characterized by the above-mentioned. A machine tool comprising a cutting tool made of the surface coating material according to any one of claims 1 to 7.

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