JP6168540B2 - Hard lubricant coating and hard lubricant coating tool - Google Patents

Description

  The present invention relates to a hard lubricating coating provided on the surface of a base material and a hard lubricating coating-coated tool coated with the hard lubricating coating, and more particularly to an improvement for improving both hardness and wear resistance.

  Cutting tools such as drills and taps that cut materials such as carbon steel, stainless steel, and mild steel have properties such as wear resistance that can increase the hardness and tool life required to cut the work material. Desired. Therefore, a hard coating is provided on the surface of the base material of the cutting tool so as to improve the wear resistance. As this hard coating for cutting tools, coatings such as TiN, CrN, and TiAlN are widely used, and improvements are made to further improve the performance. For example, the hard laminated film described in patent document 1 and patent document 2 is it.

For example, in Patent Document 1, first made of _{Ti a Cr b Al c Mo 1} -abc nitride or a first coating layer made of _{carbonitride, Ti d Cr e Al 1-} de nitride or carbonitride A hard laminated film composed of a multilayer film in which two or more film layers are alternately laminated, and in Patent Document 2, from Ti _a Cr _b Al _c Mo _1-abc nitride or carbonitride. A hard laminate coating composed of a single layer film is proposed.

JP2012-115924 JP2012-115923A

  However, the base material on which the hard multilayer coating is formed by the conventional technology as described above is still insufficient in lubricity and wear resistance. Therefore, a cutting tool composed of the base material due to chipping or wear has an early life. There was a problem that it might lead to. Accordingly, there has been a demand for the development of a hard laminate film that is hard and wear-resistant.

  The present invention has been made against the background of the above circumstances, and an object of the present invention is to provide a hard lubricant film and a hard lubricant film-coated tool that are hard and wear-resistant.

  While the present inventors have intensively studied against the background of the above situation, the layer A is composed of chromium (Cr), molybdenum (Mo), tungsten (W), vanadium (V) and boron (B) as constituent elements. When a B layer having titanium (Ti) and silicon (Si) as constituent elements is inserted and oxygen is introduced into the A layer, an oxycarbide, oxynitride or oxycarbonitride of Cr, Mo, W and V It has been found that since a fine structure of the crystal is formed, higher lubricity can be obtained while having high hardness. The present invention has been made based on such findings. In the layered structure with the B layer, the crystal of the A layer has a fine crystal structure in which crystal growth is suppressed by the thickness of the layer to increase the hardness of the coating, and the oxycarbide of Cr, Mo, W and V, The crystal of oxynitride or oxycarbonitride has a solid lubricating structure similar to that of molybdenum sulfide or nitride, and thus it is estimated that the lubricity of the coating is improved.

That is, the gist of the first invention is a hard lubricating film coated on the surface of the base material, and (Cr _a Mo _b W _c V _d B _e ) _1-x-yz C _x N _y O _z oxycarbide of the a layer made of oxynitride or oxycarbonitride _{compound, (Ti 1-f Si f} ) 1-g N g is the composed B layer from rigid laminated alternately in two layers or more lubricating The atomic ratio a relating to the A layer is 0.2 ≦ a ≦ 0.7, b is 0.05 ≦ b ≦ 0.6, c is 0 ≦ c ≦ 0.3, d is 0 ≦ d ≦ 0.05, e = 1−a−b−c−d is 0 ≦ e ≦ 0.05, x is 0 ≦ x ≦ 0.6, y is 0 ≦ y ≦ 0.6, and z is 0 < z ≦ 0.2, x + y + z is 0.3 ≦ x + y + z ≦ 0.6, the atomic ratio f related to the B layer is 0 <f ≦ 0.4, and g is 0.4 ≦ g ≦ 0.6. And the thickness of the A layer is 2 nm or more and 50 Hard lubrication film and hard lubrication coated with a hard lubrication film, wherein the thickness of the B layer is in the range of 1 nm to 500 nm and the total film thickness is in the range of 0.1 μm to 10.0 μm In coating tool.

  The gist of the second invention is the hard lubricating film of the first invention, wherein the A layer has a multiphase structure in which a crystalline phase and an amorphous phase are mixed.

As described above, the hard lubricating coating of the first invention is an oxycarbide, oxynitride or oxycarbonitride of (Cr _a Mo _b W _c V _d B _e ) _1-xyz C _x N _y O _z Since the A layer made of a material and the B layer made of (Ti _1-f Si _f ) _1-g N _g are alternately laminated, two or more layers are formed. The hardness of the film is increased by forming a microstructure composed of oxides, oxycarbides, oxynitrides or oxycarbonitrides of Mo, W and V, and oxides, oxycarbides of Mo, W and V Since oxynitride or oxycarbonitride has solid lubricity, the lubricity of the film is enhanced, and therefore, a hard lubricant film and a hard lubricant film-coated tool having hard and wear resistance can be obtained. .

According to the hard lubricating film of the second invention, the A layer has a multiphase structure in which a crystalline phase and an amorphous phase are mixed. Thus, a fine NaCl-structure crystal phase (δ- (Cr, Mo, W, V) N, γ-Mo ₂ N, etc.) made of Mo, W and V oxycarbides, oxynitrides or oxycarbonitrides ) And an amorphous phase are formed, whereby a hard lubricating coating and a hard lubricating coating-coated tool having hard and wear resistance can be obtained.

It is a figure which shows the drill provided with the hard film of this invention, (a) is a front view, (b) is the enlarged bottom view seen from the front end side. FIG. 2 is a conceptual cross-sectional view for explaining a laminated structure of a surface portion of a body in the drill of FIG. 1. It is a process chart for forming the drill of FIG. It is a schematic block diagram explaining the sputtering device used suitably when forming the drill of FIG. It is the graph which showed the abrasion width (mm) obtained by the cutting test of the drill with which the hardness H (GPa) of the film of the hard film and the hard film were coat | covered for every test goods 1-35 and the comparative goods 1-6. . It is a graph which shows transition of the wear width accompanying the increase in the number of processing holes in a cutting test. 2 is a photograph taken by a transmission electron microscope (TEM) of layer A in the hard coating of test product 1. FIG.

  Hereinafter, an embodiment of the hard lubricating coating of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a view showing a drill 12 provided with a hard coating 10 according to the present invention, where (a) is a front view seen from a direction perpendicular to the axis O, and (b) is a tip side provided with a cutting edge 14. It is the enlarged bottom view seen from. The drill 12 is a two-blade twist drill, and is integrally provided with a shank 16 and a body 18 in the axial direction. A pair of grooves 20 twisted clockwise around the axis O is formed in the body 18. . A pair of cutting edges 14 are provided at the tip of the body 18 corresponding to the grooves 20, and a hole is cut by the cutting edges 14 by being driven to rotate clockwise around the axis O as viewed from the shank 16 side. While processing, chips are discharged through the groove 20 to the shank 16 side. The hard coating 10 corresponds to the hard lubricating coating of the present invention, and the drill 12 corresponds to the hard lubricating coating coated tool of the present invention.

FIG. 2 is a conceptual cross-sectional view for explaining the laminated structure of the surface portion of the body 18 in the drill 12 of FIG. As shown in FIG. 2, a hard coating 10 that covers the surface of the tool base material 22 made of cemented carbide, which is the base material of the drill 12, is coated. The hatched portion in FIG. 1 shows a portion of the drill 12 where the hard coating 10 is provided. The hard coating 10 is preferably coated on the surface of the tool base material 22 corresponding to the body 18 in the drill 12. Provided. The tool base material 22 corresponds to the base material of the present invention.

As is apparent from FIG. 2, the hard coating 10 of the present example is a multilayer in which two or more A layers 24 containing oxygen elements and B layers 25 containing titanium (Ti) and silicon (Si) are alternately laminated. It is a film | membrane, Such A layer 24 and B layer 25 are comprised from the material which satisfies the chemical composition shown below. That is, the A layer 24 is an oxycarbide, oxynitride, or oxycarbonitride of (Cr _a Mo _b W _c V _d B _e ) _1-x-yz C _x N _y O _z having an atomic ratio a is 0.2 ≦ a ≦ 0.7, b is 0.05 ≦ b ≦ 0.6, c is 0 ≦ c ≦ 0.3, d is 0 ≦ d ≦ 0.05, e = 1−a−. b-c-d is 0 ≦ e ≦ 0.05, x is 0 ≦ x ≦ 0.6, y is 0 ≦ y ≦ 0.6, z is 0 <z ≦ 0.2, x + y + z is 0.3 ≦ x + y + z ≦ 0.6. In the A layer 24, a microstructure made of oxides, oxycarbides, oxynitrides or oxycarbonitrides of Mo, W and V having a solid lubricating structure similar to molybdenum sulfide or nitride is formed. As the layer 24, for example, (Cr _0.4 Mo _0.6 ) _0.48 N _0.4 O _0.12 is preferably exemplified. Further, the B layer 25 is (Ti _1-f Si _f ) _1-g N _g , and the atomic ratio f is 0 <f ≦ 0.4, and g is 0.4 ≦ g ≦ 0.6. B layer 25 is mostly and having a hard property consists crystalline phase, having good heat resistance and a child silicon (Si) is contained. As the B layer 25 in the hard coating 10, (Ti _0.9 Si _0.1 ) _0.5 N _{0.5 and the} like are preferably exemplified.

  In the hard coating 10, the thickness D1 of the A layer 24 is in the range of 2 nm to 500 nm, the thickness D2 of the B layer 25 is in the range of 1 nm to 500 nm, and the total thickness D of the hard coating 10 is 0. It is set within a range of 1 μm or more and 10.0 μm or less. The number of layers of the A layer 24 and the B layer 25 is appropriately determined as long as it does not deviate from the above numerical range related to the total film thickness D of the hard coating 10 and the film thicknesses D1 and D2 of the coating layers 24 and 25. Since the hardness is higher when it is composed of multiple layers, a multilayer film having at least one A layer 24 and one B layer 25 is provided. Further, the film thicknesses D1 of the plurality of A layers 24 in the hard coating 10 may be all equal or may be different from each other within the above numerical range. Similarly, the film thicknesses D2 of the plurality of B layers 25 in the hard coating 10 may all be equal, or may be different from each other within the above numerical range.

  Further, in the hard coating 10, the stacking order of the A layer 24 and the B layer 25 is preferably B layer 25, A layer 24,..., B layer 25 from the tool base material 22 side as shown in FIG. The surface layer of the hard coating 10 (the uppermost layer of the hard coating 10, that is, the layer coated on the tool base material 22) is the A layer 24. Since the A layer 24 has a smaller coefficient of friction than the B layer 25, the hard coating 10 can be provided with good wear resistance by using the A layer 24 as the surface layer.

  Next, the process of forming the drill 12 in which the part corresponding to the body 18 of the tool base material 22 is coated with the hard coating 10 will be described in detail with reference to FIGS. FIG. 3 is a process chart for forming the drill 12 of FIG. 1, and FIG. 4 is a schematic configuration diagram (schematic diagram) for explaining a sputtering apparatus 26 suitably used for forming the drill 12 of FIG. .

  In the base material grinding step P <b> 1 in FIG. 3, grinding is performed on the cemented carbide which is the base material of the tool base material 22, and the tool base material 22 is obtained. For example, the cemented carbide is first subjected to cylindrical grinding to form a rough shape of the tool base material 22, that is, a cylindrical shape that becomes the shank 16 and the body 18 having an axial center. Next, groove grinding is performed to form a groove 20 or the like twisted clockwise about the axis O on the outer peripheral side surface on one end in the longitudinal direction corresponding to the cylindrical body 18. Finally, blade sharpening is applied to one end in the longitudinal direction so that a cutting edge 14 for cutting the work material is formed. Next, in the cleaning process P <b> 2, the surface of the tool base material 22 is cleaned prior to the coating of the hard coating 10. In the etching process P3, the surface of the tool base material 22 is roughened as a pretreatment by the sputtering apparatus 26. In the film forming step P4 of the coating 10, the drill 12 is formed by coating the hard coating 10 on the body 18 of the tool base material 22 by the sputtering device 26. In the inspection process P5, an inspection is performed to determine whether or not the drill 12 coated with the hard coating 10 satisfies the use standard as a cutting tool.

Next, the etching process P3 and the film forming process P4 performed by the sputtering apparatus 26 will be described in more detail with reference to FIG. The sputtering apparatus 26 includes a chamber 28, a rotating shaft that passes through a substantially central through hole in the bottom surface of the chamber 28, and a disk-shaped base 30 that is fixed to one end of the rotating shaft inside the chamber 28. . First, on the disk-shaped base 30, a plurality of tool base materials 22 obtained in the grinding step P <b> 1 at equal intervals in the circumferential direction on the circumference located at equal intervals from the center of the base 30. It is installed on the base 30 so as to be able to rotate. The tool base material 22 is heated to about 500 ° C. by a heater (not shown), and argon (Ar) gas is introduced into the chamber 28 while the inside of the chamber 28 is maintained at a vacuum level equal to or lower than a predetermined pressure. In this state, a bias voltage of −200 to −500 V, for example, is applied to the tool base material 22 by the bias power source 32, and the surface of the tool base material 22 is etched by Ar ions generated by glow discharge generated in Ar gas. Is called. After the etching process is completed, Ar gas is exhausted from the chamber 28. After the etching process P3 is completed as described above, a film forming process P4 is subsequently performed. That is, a constant cathode voltage (for example, about −100 to −500 V) is applied to the targets 34 and 35 such as Cr, Mo, Ti, and Si constituting the hard coating 10 by the power source 36, and the tool mother is applied by the bias power source 32. By applying a constant negative bias voltage (for example, about −100 V) to the material 22, argon ions Ar + collide with the targets 34 and 35 to strike out ionizing components such as Cr, Mo, Ti, and Si. Let The voltage applied by the power source 36 and the bias power source 32 is controlled by a controller 38. In the chamber 28, a reactive gas such as nitrogen gas (N ₂ ), hydrocarbon gas (CH ₄ , C ₂ H ₂ ) or oxygen gas (O ₂ ) in addition to argon gas is selectively selected at a predetermined flow rate and pressure. The nitrogen atom (N), carbon atom (C), or oxygen atom (O) is introduced and combined with Cr, Mo, Ti, Si or the like knocked out from the targets 34, 35 to form an A layer 24, for example (Cr _An oxynitride such as _0.4 Mo _0.6 ) _0.48 N _0.4 O _0.12 or an oxycarbide such as (Cr _0.25 Mo _0.45 W _0.28 V _0.02 ) _0.63 C _0.2 O _0.17 is formed as the B layer 25, for example (Ti _0.9 Si _0.1 ) _0.5 N _0.5 is formed. And since the tool base material 22 is further rotated with respect to the base 30 on the base 30 rotated with respect to the chamber 28, they are coated on the surface of the tool base 22 as a homogeneous hard coating 10. It is done. Here, the A layer 24 and the B layer 25 are controlled only by controlling the composition ratios related to Cr, Mo, W, V, and B and various reaction gases during film formation, or only by controlling various reaction gases during film formation. A coating of is formed. For example, hydrocarbon gas as a reaction gas in the coating layer B 25 is _{(CH 4, C 2 H 2} ) and oxygen _{(O 2)} for gas is not necessary, a hydrocarbon gas (CH _4, C ₂ H ₂ ) And oxygen (O ₂ ) gas into the chamber 28 are turned off to form the B layer 25. Then, according to the switching of the reaction gas and the selection of the targets 34 and 35, the alternate coating of the tool base material 22 with the A layer 24 and the B layer 25 is repeated, and finally the hard coating 10 is coated. A hard alloy drill 12 is formed.

The hard coating 10 thus coated on the drill 12 is made of (Cr _a Mo _b W _c V _d B _e ) _1-x-yz C _x N _y O _z oxycarbide, oxynitride or oxycarbonitride comprising at which the a layer 24 and the _{(Ti 1-f Si f)} 1-g N g of the B layer 25 is a crystalline layer are laminated alternately ones, i.e. B layer 25 is inserted into the film interface of a layer 24 Therefore, since the particle diameter of the coating particles constituting the A layer 24 and the B layer 25 is further reduced and a fine structure is formed, the wear resistance is excellent, and consequently the tool life of the drill 12 is improved. Result in improvement. In addition, since solid lubricant particles are generated by the self-formation of Mo, W, and V oxides when worn, the wear life is excellent in low wear and welding resistance. As a result, the tool life of the drill 12 can be extended. .

  Next, the drill 12 coated with the hard coating 10, that is, the test conducted by the present inventors in order to verify the effect of the present invention will be described in detail with reference to FIGS. 5 to 7, Table 1 and Table 2. FIG.

  First, the thin film composition of the A layer 24 and the B layer 25 shown in Table 1 and the film having the respective film thicknesses D1 and D2 and the total film thickness D of the A layer 24 and the B layer 25 shown in Table 2, that is, the hard film 10 The coating satisfying the required conditions was coated on a carbide drill with a tool diameter of 6 mmφ through steps P2, P3 and P4 in FIG. 3, and drills 12 of test products 1 to 35 were formed. In addition, for comparison, a coating that does not satisfy the conditions of the hard coating 10 was similarly coated with a carbide drill with a tool diameter of 6 mmφ through the steps P2, P3, and P4, and drills of comparative products 1 to 6 were formed. .

  The hardness H (GPa) of the film in Table 2 was determined as follows. The hardness of each film | membrane was measured according to the nanoindentation method about the test products 1-35 and the comparative products 1-6. That is, a triangular pyramid type indenter having a tip of a diamond tip (Berkovic type) is pressed into the surface of each of the test products 1 to 35 and the comparative products 1 to 6 coated with a hard film with a load P, and a projected area A under the indenter Was calculated. The film hardness H (GPa) is calculated by dividing the load P by the area A. In the nanoindentation method, the hardness is evaluated as soft at 15 to 20 GPa, hard at 30 GPa or more, and brittle at 50 to 60 GPa.

  Further, the wear width (mm) after processing 5000 holes in Table 2 was obtained by conducting a cutting test under the following cutting conditions on the drills 12 of the test products 1 to 35 and the drills of the comparative products 1 to 6.

[Cutting conditions]
-Test product and comparative product: Carbide drill, tool diameter 6 (mmφ)
・ Work material: S50C
・ Cutting method: Hole machining ・ Cutting speed: 100 (m / min)
・ Feeding speed: 955 (mm / min)
・ Processing depth: 30mm stop ・ Cutting oil: Water-soluble

  In the cutting test, the wear width after the 5000 hole processing shown in Table 2 is the outer peripheral portion of the cutting edge 14 in the drills 12 of the test products 1 to 35 and the drills of the comparative products 1 to 6 after the 5000 holes processing under the above cutting conditions. The wear width (mm) in the circumferential direction of the (corner portion). When the wear width was 0.2 mm or less, it was determined to be acceptable, and when the wear width was greater than 0.2 mm, it was determined to be unacceptable. In addition, in the remarks in Table 2, “continuation is possible” refers to the case where the subsequent drilling is possible in the drill after drilling 5000 holes. If the subsequent cutting is impossible, the state of the drill subjected to the cutting test is indicated. evaluated.

FIG. 5 shows the hardness H (GPa) of the film obtained by the nanoindentation method and the wear width after machining 5000 holes obtained by the cutting test (mm) for each of the test products 1 to 35 and the comparative products 1 to 6. It is a graph. That is, FIG. 5 is a graph of the hardness H (GPa) and the wear width (mm) after processing 5000 holes in Table 2. Incidentally, the horizontal axis is the number of specimens 1 to 35 and Comparative products 1 to 6 of FIG. 5, the hardness H (GPa) of the left vertical axis specimens 1 to 35 and Comparative products 1 to 6 film, right the vertical axis represents specimens 1-35 and comparative 1-6 5000 drilling after abrasion width (mm) respectively. As shown in Table 2 and FIG. 5, in all the drills 12 of the test products 1 to 35 coated with the coating satisfying the requirements of the hard coating 10, the hardness H (GPa) of the film is 29.0 GPa or more, The wear width (mm) after processing 5000 holes was 0.198 mm or less, and was evaluated as passing in the cutting test. In addition, all of the test products 1 to 35 were able to continue the subsequent cutting because the wear width was small even after processing 5000 holes.

  FIG. 6 is a graph showing the transition of the wear width associated with an increase in the number of holes processed in the cutting test. The test products 3, 17 and 22, and the comparative products 4 and 5 are the test products 1 to 35 and the comparative products 1 to 1, respectively. Plotted on behalf of 6. As shown in FIG. 6, with the increase in the number of processed holes, the specimens 3, 17 and 22 gradually increased in wear width (mm), and the wear width after processing 5000 holes was about 0.200 mm. .

That is, from the above results, the (Ala layer 24 made of oxycarbide, oxynitride or oxycarbonitride of (Cr _a Mo _b W _c V _d B _e ) _1-xyz C _x N _y O _z and , (Ti _1-f Si _f ) _1-g N _g and B layers 25 are alternately stacked, and the atomic ratio a related to the A layer 24 is 0.2 ≦ a ≦ 0.7, b is 0.05 ≦ b ≦ 0.6, c is 0 ≦ c ≦ 0.3, d is 0 ≦ d ≦ 0.05, e = 1−a−b−c−d is 0 ≦ e ≦ 0.05, x is 0 ≦ x ≦ 0.6, y is 0 ≦ y ≦ 0.6, z is 0 <z ≦ 0.2, x + y + z is 0.3 ≦ x + y + z ≦ 0.6, The atomic ratio f related to the B layer 25 is 0 <f ≦ 0.4, g is 0.4 ≦ g ≦ 0.6, and the film thickness D1 of the A layer 24 is 2 nm to 500 nm. Film thickness D2 is 1 nm to 500 nm The drill 12 of the test products 1 to 35 coated with the hard coating 10 having a total film thickness D in the range of 0.1 μm or more and 10.0 μm or less has a film hardness H of 29.0 GPa or more and The wear width (mm) after processing 5000 holes was 0.198 mm or less, indicating a good value.

On the other hand, the comparative product 1 is a drill in which a single layer film of A layer having a thickness of 6300 nm made of (Ti _0.2 Cr _0.4 Mo _0.4 ) _0.45 C _0.05 N _0.2 O _0.3 is coated, and in the A layer, titanium (Ti) Is contained, and the atomic ratio z of oxygen is 0.3. Therefore, an element titanium (Ti) different from the thin film composition related to the A layer 24 of the hard coating 10 is contained, and oxygen (O) is contained. Since the atomic ratio z deviates from 0 <z ≦ 0.2, and the B layer is not inserted at the thin film interface of the A layer, the A layer 24 and the B layer 25 of the hard coating 10 are alternately laminated. The film thickness of the A layer deviates from the range of 2 nm or more and 500 nm or less of the film thickness D1 of the A layer 24 related to the hard coating 10. Therefore, the hardness H of the film of the drill of the comparative product 1 was 31.0 GPa, but the wear width after processing 5000 holes is 0.428 mm, which is a large value compared with the test product and is judged as rejected. It was. In the cutting test, after 2000 holes were drilled, the wear width of the corner of the drill became too large, and continuous use became impossible. From this result, in particular, the atomic ratio z of oxygen (O) related to the A layer 24 should be 0.2 or less, the film thickness D1 related to the A layer should be 500 nm or less, and the B layer 25 is a thin film of the A layer 24 It was verified that the A layer 24 and the B layer 25 should be laminated alternately by being inserted at the interface, and the significance of the requirements required for the hard coating 10 according to the present invention was confirmed.

Comparative product 2 is a drill coated with a single layer film of 11500 nm in thickness A made of Mo _0.6 N _0.4 , and the A layer does not contain chromium (Cr) and oxygen (O), Since the atomic ratio b of molybdenum (Mo) is 1, 0.2 ≦ a ≦ 0.7 of the atomic ratio a of chromium (Cr) related to the A layer 24 of the hard coating 10, and the atomic ratio b of molybdenum (Mo) 0.05 ≦ b ≦ 0.6 and oxygen (O) atomic ratio z 0 <z ≦ 0.2, respectively, and the B layer is not inserted and formed at the thin film interface of the A layer. Deviating from the requirement that 10 A layers 24 and B layers 25 are alternately stacked, the thickness of the A layer and the total thickness are 2 nm or more and 500 nm or less of the thickness D1 of the A layer 24 related to the hard coating 10. The total film thickness D deviates from the range of 0.1 μm to 10.0 μm. Therefore, the hardness H of the film of the drill of the comparative product 2 is 19.3 GPa, which is small compared to the test product, and the wear width after drilling 5000 holes is 0.765 mm, which is a large value compared to the test product and is not good. It was determined to pass. In the cutting test, after 3100 holes were drilled, the wear width of the corner of the drill became too large, and continuous use became impossible. From this result, in particular, the atomic ratio a of chromium (Cr) in the A layer 24 is 0.2 or more, the atomic ratio b of molybdenum (Mo) is 0.6 or less, and the atomic ratio z of oxygen (O) is less than 0. The film thickness D1 related to the A layer 24 should be 500 nm or less, the total film thickness D should be 10.0 μm or less, and the B layer 25 is formed at the thin film interface of the A layer 24. It was verified that the layers 25 should be alternately stacked, and the significance of the requirements required for the hard coating 10 according to the present invention was confirmed.

Comparative product 3 is a drill in which a single layer film of A layer having a thickness of 8500 nm made of (Ti _0.5 Mo _0.5 ) _0.4 C _0.1 N _0.2 O _0.3 is coated, and titanium (Ti) is contained in the A layer. Since the chromium (Cr) is not contained and the atomic ratio z of oxygen (O) is 0.3, element titanium (Ti) different from the thin film composition related to the A layer 24 of the hard coating 10 is formed. It is contained, and 0.2 ≦ atomic ratio a of chromium (Cr) a ≦ 0.7, departing from the 0 <z ≦ 0.2 in atomic ratio z of oxygen (O), B layer a Since it is not inserted at the thin film interface of the layers, it deviates from the requirement that the A layer 24 and the B layer 25 of the hard coating 10 are alternately laminated, and the A layer has a film thickness of the A The thickness D1 of 24 deviates from the range of 2 nm to 500 nm. Therefore, the hardness H of the film of the drill of the comparative product 3 is 25.3 GPa, which is small compared to the test product, and the wear width after drilling 5000 holes is 0.622 mm. It was determined to pass. In the cutting test, since the corner portion of the drill was broken after 2799 holes were drilled, continuous use was impossible. From this result, in particular, the atomic ratio a of chromium (Cr) related to the A layer 24 is 0.2 or more, the atomic ratio z of oxygen (O) is 0.2 or less, and the film pressure D1 related to the A layer 24 is 500 nm or less. It is verified that the B layer 25 is inserted and formed at the thin film interface of the A layer 24, and the A layer 24 and the B layer 25 should be alternately laminated. The significance of the requirements required for this was confirmed.

Comparative product 4 is a stack of two or more alternating layers of 1 nm thick A layer made of Ti _0.73 C _0.1 N _0.15 O _0.02 and 2 nm thick B layer made of (Ti _0.45 Si _0.55 ) _0.85 N _0.15. Is a drill coated with a multilayer film having a total film thickness of 5.00 μm, which contains titanium (Ti) in the A layer and does not contain chromium (Cr) and molybdenum (Mo). Since the total x + y + z of the atomic ratio of carbon (C), nitrogen (N), and oxygen (O) is 0.27, elemental titanium (Ti) different from the thin film composition related to the A layer 24 of the hard coating 10 is contained. And an atomic ratio a of chromium (Cr) 0.2 ≦ a ≦ 0.7, an atomic ratio b of molybdenum (Mo) 0.05 ≦ b ≦ 0.6, carbon (C) and nitrogen ( N) and the sum of atomic ratios of oxygen (O) x + y + z, 0.3 ≦ x + y + z ≦ 0.6 Since the atomic ratio f of silicon (Si) in the B layer is 0.55 and the atomic ratio g of nitrogen (N) is 0.15, the atomic ratio f of silicon (Si) in the B layer of the hard coating 10 0 <f ≦ 0.4, the atomic ratio g of nitrogen (N) is 0.4 ≦ g ≦ 0.6, and the thickness of the A layer is equal to the thickness D1 of the A layer 24 according to the hard coating 10. It deviates from the range of 2 nm or more and 500 nm or less. Therefore, the hardness H of the film of the drill of the comparative product 4 is 21.0 GPa, which is a small value compared to the test product, and the wear width (mm) after drilling 5000 holes is 0.550 mm, compared with the test product. It was a large value and was judged to be unacceptable. As shown in FIG. 6, the wear width exceeds 0.1 mm after drilling 2000 holes, and then the wear width increases rapidly as the number of drilled holes increases, and the wear width at the corner of the drill after drilling 3619 holes. Became too large for continuous use. From this result, in particular, the atomic ratio a of chromium (Cr) in the A layer 24 is 0.2 or more, the atomic ratio b of molybdenum (Mo) is 0.05 or more, carbon (C), nitrogen (N), and oxygen ( O) The sum of atomic ratios x + y + z is 0.3 or more, the atomic ratio f of silicon (Si) related to the B layer 25 is 0.4 or less, the atomic ratio g of nitrogen is 0.4 or more, and the film related to the A layer 24 It was verified that the thickness D1 should be 2 nm or more, and the significance of the numerical range required for the hard coating 10 according to the present invention was confirmed.

Comparative product 5 is composed of two alternating layers of 800 nm thick A layers composed of (Ti _0.1 Cr _0.5 Mo _0.4 ) _0.55 N _0.45 and 600 nm thick B layers composed of (Ti _0.7 Si _0.3 ) _0.6 N _0.4. It is a drill coated with a multilayer film with a total film thickness of 7.00 μm formed by laminating more than one layer, and contains hard titanium (Ti) and no oxygen (O) in the A layer. An element titanium (Ti) different from the thin film composition related to the A layer 24 of the coating 10 is contained, and the atomic ratio z of oxygen (O) deviates from 0 <z ≦ 0.2. The respective film thicknesses deviate from the range of 2 nm to 500 nm of the film thickness D1 related to the A layer 24 of the hard coating 10 and the film thickness D2 of 1 nm to 500 nm related to the B layer 25. Therefore, although the hardness H of the film of the drill of the comparative product 5 was 36.6 GPa, the wear width (mm) after processing 5000 holes is 0.369 mm, which is a large value compared with the test product and is rejected. It was determined. As shown in FIG. 6, the wear width exceeds 0.1 mm after drilling 2000 holes, and the wear width gradually increases after that, and the corner of the drill breaks after drilling 4571 holes, and continuous use is impossible. became. From this result, in particular, the atomic ratio z of oxygen (O) related to the A layer 24 should be larger than 0, the film thickness D1 related to the A layer 24 should be 500 nm or less, and the film thickness D2 related to the B layer 25 should be 500 nm or less. And the significance of the numerical range required for the hard coating 10 according to the present invention was confirmed.

Comparative product 6 is a 650 nm thick A layer made of (Ti _0.5 Cr _0.15 Mo _0.2 W _0.15 ) _0.25 C _0.1 N _0.2 O _0.45 and a 1 nm thick B layer made of (Ti _0.55 Si _0.45 ) _0.75 N _0.25. Are drills coated with a multilayer film having a total film thickness of 6.52 μm formed by alternately laminating two or more layers, and titanium (Ti) is contained in layer A, and atoms of chromium (Cr) The ratio a is 0.15, the atomic ratio z of oxygen (O) is 0.45, and the sum x + y + z of the atomic ratios of carbon (C), nitrogen (N), and oxygen (O) is 0.75. Therefore, elemental titanium (Ti) different from the thin film composition related to the A layer 24 of the hard coating 10 is contained, the atomic ratio a of chromium (Cr) is 0.2 ≦ a ≦ 0.7, oxygen (O) 0 <z ≦ 0.2 of the atomic ratio z, and the sum of the atomic ratios of carbon (C), nitrogen (N), and oxygen (O) x + + Z of 0.3 ≦ x + y + z ≦ 0.6, and in the B layer, the atomic ratio f of silicon (Si) is 0.45 and the atomic ratio g of nitrogen (N) is 0.25. The film thickness of the A layer deviates from 0 <f ≦ 0.4 of the atomic ratio f of silicon (Si) in the B layer and 0.4 ≦ g ≦ 0.6 of the atomic ratio g of nitrogen (N). However, it deviates from the range of 2 nm or more and 500 nm or less of the film thickness D1 related to the A layer 24 of the hard coating 10. Therefore, the hardness H of the film of the drill of the comparative product 6 was 39.4 GPa, but the wear width (mm) after processing 5000 holes is 0.394 mm, which is a large value compared to the test product and is rejected. It was determined. In the cutting test, the corner portion of the drill broke after 1100 holes were drilled, making continuous use impossible. From this result, in particular, the atomic ratio a of chromium (Cr) in the A layer 24 is 0.2 or more, the atomic ratio z of oxygen (O) is 0.2 or less, carbon (C), nitrogen (N), and oxygen ( The sum x + y + z of the atomic ratio of O) is 0.6 or less, the atomic ratio f of silicon (Si) according to the B layer 25 is 0.4 or less, the atomic ratio g of nitrogen is 0.4 or more, and the film according to the A layer 24 It was verified that the thickness D1 should be 500 nm or less, and the significance of the numerical range according to the present invention was confirmed.

  From the results of the film hardness test and the cutting test, the drills 12 of the specimens 1 to 35 shown in Table 2 have a large value in the film hardness H and a small wear width (mm) after processing 5000 holes. A value was obtained, indicating high hardness and good wear resistance. On the other hand, the drills of the comparative products 1 to 6 that deviate from the ranges of the thin film composition, the atomic ratio of each element, each film thickness, and the total film thickness required for the hard coating 10, Although the hardness was 30 GPa or more, the wear width (mm) after processing 5000 holes was a large value as compared with the test products 1 to 35, and both hardness and wear resistance were not satisfied.

Next, the A layer 24 in each of the hard coatings 10 of the test products 1 to 35 having high hardness and excellent wear resistance was observed with a transmission electron microscope (TEM). FIG. 7 is a photograph of a cross section of the A layer 24 in the hard coating 10 of the test product 1 taken with a transmission electron microscope (TEM). As a result, in the A layer 24, crystal phases (δ- (Cr, Mo, W, V) N, γ-Mo ₂ N, etc.) 40 composed of fine crystal grains, which are regions where lattice fringes in FIG. 7 are observed. When oxygen multiphase structure of the amorphous phase 42 containing (O ₂₎ has been formed which is the other area. Since the drill 12 coated with the hard coating 10 having the A layer 24 has a crystal phase 40 composed of fine crystal grains, the hardness H of the film is as high as 30.0 GPa. 24, since the amorphous phase 42 containing oxygen (O ₂ ) is present, formation of molybdenum (Mo), tungsten (W) and vanadium (V) oxide due to wear is promoted, so that low wear and welding resistance are achieved. As a result, the wear width after drilling 5000 holes is 0.125 mm and has good wear resistance.

As described above, according to the hard coating 10 covered with the drill 12 of the test products 1 to 35 of the present embodiment, the hard coating 10 is provided on the surface of the tool base material 22 (Cr _a Mo _b W _c V _d B _e ). _{1-x-y-z C} x N y O z acids carbides, the a layer 24 made of oxynitride or oxycarbonitride _thereof, B layer 25 made of _{(Ti 1-f Si f)} 1-g N g Are formed by alternately laminating two or more layers, the atomic ratio a relating to the A layer 24 is 0.2 ≦ a ≦ 0.7, b is 0.05 ≦ b ≦ 0.6, c Is 0 ≦ c ≦ 0.3, d is 0 ≦ d ≦ 0.05, e = 1−a−b−c−d is 0 ≦ e ≦ 0.05, x is 0 ≦ x ≦ 0.6, y Is 0 ≦ y ≦ 0.6, z is 0 <z ≦ 0.2, x + y + z is 0.3 ≦ x + y + z ≦ 0.6, and the atomic ratio f related to the B layer 25 is 0 <f ≦ 0.4, g is 0.4 ≦ g ≦ 0.6 The A layer 24 has a thickness D1 of 2 nm to 500 nm, the B layer 25 has a thickness D2 of 1 nm to 500 nm, and the total thickness D is in the range of 0.1 μm to 10.0 μm. Further, the A layer 24 is formed with a microstructure made of oxides of Mo, W and V, oxycarbides, oxynitrides or oxycarbonitrides, so that the hardness of the coating is increased, and Mo, W and V Oxide, oxycarbide, oxynitride, or oxycarbonitride has solid lubricity, so that the lubricity of the film is enhanced, so that hard coating 10 and drill 12 having hardness and wear resistance are obtained. Can do.

In addition, according to the hard coating 10 covered with the drills 12 of the test products 1 to 35 of this example, the A layer 24 has a multiphase structure in which the crystal phase 40 and the amorphous phase 42 are mixed. Thus, a fine NaCl-structure crystal phase (δ- (Cr, Mo, W, V) N, γ-Mo ₂ N, etc.) made of Mo, W and V oxycarbides, oxynitrides or oxycarbonitrides ) By forming a multiphase structure of 40 and the amorphous phase 42, it is possible to obtain the hard coating 10 and the drill 12 that are hard and wear resistant.

  As mentioned above, although this invention was demonstrated in detail with reference to the table | surface and drawing, this invention can be implemented in another aspect, and can be variously changed in the range which does not deviate from the main point.

  For example, in the above-described embodiment, the stacking order of the A layer 24 and the B layer 25 in the hard coating 10 is B layer 25, A layer 24,..., B layer from the tool base material 22 side as shown in FIG. 25 and the A layer 24 in this order. That is, the base layer of the hard coating 10 (the lowermost layer in contact with the tool base material 22) is the B layer 25, and the surface layer (the uppermost layer of the hard coating 10) is the A layer 24. 24 is not necessarily limited to such a configuration, and the base layer may be the A layer 24.

  Further, in the above-described embodiment, the hard coating 10 is coated with the drill 12, but is not limited to this. For example, a cutting tool such as an end mill, a tap, or a die, or a metal such as punching or bending. You may coat | cover with metal processing tools, such as a metal mold | die for a process.

  In the above-described embodiment, the hard coating 10 is coated with the sputtering apparatus 26 when the drill 12 is formed. However, the present invention is not limited to this. For example, other than the arc ion plating method, etc. The physical coating method (PVD method) or chemical vapor deposition method (CVD method) such as plasma CVD method or thermal CVD method may be used to coat the hard coating 10.

10: Hard coating (hard lubricating coating)
12: Drill (hard lubricant coated tool)
24: A layer 25: B layer

Claims (3)

It is a hard lubricating film that is coated on the surface of the base material,
(Cr _a Mo _b W _c V _d B _e ) _1-x-yz C layer of an oxycarbide, oxynitride or oxycarbonitride of C _x N _y O _z , and (Ti _1-f Si _f ) B layer composed of _1-g N _g is a hard lubricating film in which two or more layers are alternately laminated,
The atomic ratio a relating to the A layer is 0.2 ≦ a ≦ 0.7, b is 0.05 ≦ b ≦ 0.6, c is 0 ≦ c ≦ 0.3, and d is 0 ≦ d ≦ 0.05. E = 1−a−b−c−d is 0 ≦ e ≦ 0.05, x is 0 ≦ x ≦ 0.6, y is 0 ≦ y ≦ 0.6, and z is 0 <z ≦ 0.2. , X + y + z is 0.3 ≦ x + y + z ≦ 0.6,
The atomic ratio f related to the B layer is 0 <f ≦ 0.4, g is 0.4 ≦ g ≦ 0.6,
The hard lubrication is characterized in that the A layer has a thickness of 2 nm to 500 nm, the B layer has a thickness of 1 nm to 500 nm, and the total thickness is in the range of 0.1 μm to 10.0 μm. Coating.   The hard lubricant film according to claim 1, wherein the A layer has a multiphase structure in which a crystal phase and an amorphous phase are mixed.   A hard lubricating film-coated tool coated with the hard lubricating film according to claim 1.

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