IL226024A

IL226024A - Hard film coated member and method for producing the same

Info

Publication number: IL226024A
Application number: IL226024A
Authority: IL
Original assignee: Kobe Steel Ltd
Priority date: 2010-10-29
Filing date: 2013-04-28
Publication date: 2017-07-31
Also published as: CN103168113A; IL226024A0; WO2012057000A1; CN103168113B

Abstract

The present invention provides a first hard film coated member wherein: layers A having a composition that satisfies TiaCrbAlcSidYe(BuCvNw) (wherein a, b, c, d, e, u, v and w respectively represent specific atomic ratios) and layers B having a composition that satisfies TifCrgAlh(BxCyNz) (wherein f, g, h, x, y and z respectively represent specific atomic ratios) are alternately laminated on a substrate; and when a lamination structure composed of a pair of the layer A and the layer B is considered as one unit, the thickness of the one unit is 10-50 nm and the film thickness of the hard coating film is 1-5 µm. The present invention also provides a second hard film coated member wherein: the layer A is laminated on the layer B with an intermediate layer interposed therebetween and having a thickness of 0.5 µm or less or without an intermediate layer; and the layer A has a thickness of 0.5-5.0 µm and the layer B has a thickness of 0.05-3.0 µm. [WO2012057000A1]

Description

226,024/2 HARD FILM COATED MEMBER AND METHOD FOR PRODUCING THE SAME Technical Field

[0001] The present invention relates to: a hard film coated member formed by coating the surface of a cutting tool, a slide member, a molding die, or the like with a hard film; and a method for forming the hard film.

Background Art

[0002] Cutting tools such as a tip, a drill, and an end mill and tools such as a press, a forging mold, and a punch, each of which uses a cemented carbide alloy, a cermet, a high-speed tool steel, or the like as a substrate, have heretofore been coated with hard films comprising TiN, TiC, TiCN, TiAIN, TiAlCrN, TiAlCrCN, TiAlCrSiBCN, TiCrAlSiBN, CrAlSiBYN, AlCrN, etc. with the aim of improving wear resistance.

[0003] A hard film for a cutting tool comprising TiAlCrCN and specifying the atomic ratio of each element is disclosed in Patent Literature 1 for example. Further, a hard film for a cutting tool comprising TiAlCrSiBCN and specifying the atomic ratio of each element is disclosed in Patent Literature 2. Furthermore, a technology of depositing a film by an arc ion plating method is disclosed in the literatures.

[0004] Further, a hard film comprising (M)CrAlSiBYZ (here, M represents at least one element selected from the group consisting of the 4A group elements, the 5A group elements, and the 6A group elements (excluding Cr) in the periodic law table and Z represents any one of N, CN, NO, and CNO) or CrAlSiBYZ (here, Z represents any one of N, CN, NO, and CNO) and specifying the atomic ratios of M, Cr, Al, Si, B, and Y is disclosed in Patent Literature 3. Furthermore, a hard film formed by alternately laminating hard films having compositions different from each other and specifying the thickness of each layer is disclosed. In addition, a technology of depositing a film by an arc ion plating method is disclosed.

[0005] Then a workpiece having a hard material layer (hard film) comprising AlCrX (here, X represents any one of N, C, B, CN, BN, CBN, NO, CO, BO, CNO, BNO, and CBNO) and specifying the atomic ratios of Al and Cr is disclosed in Patent Literature 4. United States Patent Application 20020168552 describes a hard film for cutting tools and processes for preparing and using same, wherein the hard film is composed of Ti, Al. Cr, Si, and B and has a relative density higher than 95%. Japanese Patent Number JP2003340606 describes a surface-covered cemented carbide made cutting tool having a hard coating layer composed of a complex nitride composed of Al, Ti and Cr formed on the surface of a cemented carbide substrate or carbonitride titanium-based cermet substrate in the layer thickness direction. 226,024/2 Citation List Patent Literature

[0006] Patent Literature 1: JP-A No. 2003-71610 Patent Literature 2: JP-A No. 2003-71611 Patent Literature 3: JP-A No. 2008-7835 Patent Literature 4: Japanese Translation of PCT International Application Publication JP-T No. 2006-524748 Disclosure of the Invention Problem to be solved by the invention

[0007] In such a hard film comprising a monolayer or a multilayer, the oxidation resistance of the film is improved by specifying the atomic ratio of a specific element. Meanwhile, it is desired to further improve the performance including wear resistance of a member in order to use the member coated with a hard film in an environment where a higher oxidation resistance is required when the member is applied to a cutting tool for dry processing for example. Further, a hard film having a wear resistance improved further than an existing hard film is desired in accordance with the recent trends of the higher hardness of a work material and the increase of cutting speed.

[0008] The present invention has been established in view of the above situation and a challenge of the present invention is to provide a hard film coated member excellent in wear resistance and a method for forming a hard film.

Means for solving the problem

[0009] The present inventors, as a result of earnest studies, have found that it is possible to improve the wear resistance of a hard film (hereunder referred to as a film occasionally) by combining A layers having a prescribed component composition and B layers having a prescribed component composition and thus forming a laminated film and specifying the thickness of one unit (namely, the lamination period) of a lamination structure comprising the A layer and the B layer.

That is, wear resistance neither improves sufficiently only by specifying the atomic ratio of a specific element in each of the A layers and the B layers nor improves sufficiently only by specifying the thickness of one unit. The present inventors have found that wear resistance improves however by controlling the component composition of a film and the thickness of one unit simultaneously.

[0010] That is, a first hard film coated member according to the present invention is a hard film coated member having a hard film on a substrate, wherein: the hard film has A layers having a composition represented by TiaCrbAlcSidYe(BuCvNw) and, when a, b, c, d, e, u, v, and w in the composition represent atomic ratios, satisfying the expressions 0.05 < a, 0.05 < b, 0.2 < a+b < 0.55, 0.4 < c < 0.7, 0.02 < d < 0.2, 0 < e < 0.1, 0 < u < 0.1 , 0 < v < 0.3, a+b+c+d+e = 1, and u+v+w = 1, and B layers having a composition represented by TifCrgAlh(BxCyNz) and, when f, g, h, x, y, and z in the composition represent atomic ratios, satisfying the expressions 0 < f, 0.05 < g, 0.25 < f+g £ 0.6, 0.4 < h < 0.75, 0 < x < 0.1, 0 < y < 0.3, f+g+h = 1, and x+y+z = 1 ; when the A layers and the B layers are alternately laminated and a lamination structure comprising a pair of the A layer and the B layer is considered as one unit, the thickness of the one unit is 10 to 50 nm; and the film thickness of the hard film is 1 to 5 mhi.

[0011] By specifying the component composition of each of the A layers and the B layers in such a configuration, the A layers come to be a film having a high oxidation resistance and a high hardness and being excellent in wear resistance and the B layers come to be a film having a high toughness and being excellent in oxidation resistance. Further, by specifying the thickness of the one unit of the lamination structure comprising the A layer and the B layer, the hardness of the film is enhanced and the wear resistance improves. Furthermore, by specifying the thickness of the whole film, a film excellent in wear resistance and hardly separable from a substrate is obtained.

[0012] Further, in a first hard film coated member according to the present invention, the integrated intensity I (200) of a diffraction peak from a (200) plane is preferably not less than twice the integrated intensity I (111) of a diffraction peak from a (111) plane when the hard film is measured through X-ray diffraction by a Q-2Q method. Furthermore, the full width at half maximum (FWHM) of a diffraction peak from a (200) plane is preferably not less than 0.7° when the hard film is measured through X-ray diffraction by a Q-2Q method.

By such a configuration, the wear resistance of the film improves further.

[0013] A method for forming a hard film in a first hard film coated member according to the present invention is characterized by depositing the hard film by an arc ion plating method or a sputtering method. Further, in the case of specifying the relationship of the integrated intensities of the diffraction peaks and controlling the FWHM to a prescribed value as stated above, a bias voltage applied to the substrate is set at a negative voltage of 130 V or more in absolute value when the hard film is deposited by an arc ion plating method or a sputtering method.

[0014] By depositing a film by an arc ion plating method or a sputtering method, it is possible to accurately control the composition of the film. Further, by setting a bias voltage applied to a substrate at a negative voltage of 130 V or more in absolute value, the integrated intensity I (200) of a diffraction peak from a (200) plane comes to be not less than twice the integrated intensity I (111) of a diffraction peak from a (111) plane when the film is measured through X-ray diffraction by a Q-2Q method and the FWHM of a diffraction peak from a (200) plane comes to be not less than 0.7° when the film is measured through X-ray diffraction by a Q-2Q method.

[0015] Further, the present inventors, as a result of earnest studies, have found that the A layer is a film having a high oxidation resistance and a high hardness and being excellent in wear resistance and the property further improves by controlling a crystal structure, the preferred orientation of a crystal, and a crystal grain size in addition to a component composition. With regard to a crystal structure, although it is already known that the hardness of a film lowers and the oxidation resistance also deteriorates when the crystal structure of the A layer comprises a mixed layer of a cubic crystal structure and a hexagonal crystal structure, by forming a cubic crystal monolayer structure, a film having a high hardness and being excellent in oxidation resistance is obtained and the wear resistance improves. With regard to the improvement in the wear resistance of the A layer, in addition to the forming of a cubic crystal monolayer structure, the hardness is enhanced and the wear resistance further improves as the crystal grain size reduces. Further, the present inventors have found that, although a cubic crystal structure is generally likely to be oriented preferentially to the (111) plane, by orienting the cubic crystal structure preferentially to the (200) plane, the cutting performance improves further. Although the A layer formed by controlling the crystal structure, the crystal grain size, and the crystal orientation in addition to the component composition is a film having a high oxidation resistance and a high hardness and being further excellent in wear resistance, when the A layer is used as a monolayer, the adhesiveness to a substrate is poor, hence exfoliation is caused, and a resultant problem is that the wear resistance deteriorates.

[0016] Meanwhile, the B layer is a film that is excellent in oxidation resistance and toughness, can easily form a cubic crystal monolayer structure, and can easily change crystal orientation by a substrate bias. A problem however is that the wear resistance is inferior to the A layer when it is used alone. The present invention solves the problem and can improve wear resistance by specifying components of the A layer and the B layer and forming a double-layered film by forming the A layer having a prescribed thickness on the B layer having a prescribed thickness. That is, by using the B layer as an underlayer, adhesion strength with a substrate can be improved and cutting performance can be improved dramatically in comparison with a monolayer film of only the A layer or the B layer. Moreover, by using the B layer having a cubic crystal structure, which is the same crystal structure as the A layer, as the underlayer and controlling the crystal orientation of the B layer to the (200) orientation, it is possible to: use the consistency at the interface between the B layer and the A layer; and form the A layer in the state of maintaining the crystal orientation of the B layer.

[0017] That is, a second hard film coated member according to the present invention is a hard film coated member having a hard film on a substrate, wherein: the hard film has an A layer having a composition represented by TiaCrbAlcSidYe(BuCvNw) and, when a, b, c, d, e, u, v, and w in the composition represent atomic ratios, satisfying the expressions 0.05 < a, 0.05 < b, 0.2 < a+b < 0.55, 0.4 < c < 0.7, 0.02 < d < 0.2, 0 < e < 0.1, 0 < u < 0.1 , 0 < v < 0.3, a+b+c+d+e = 1 , and u+v+w = 1, and a B layer having a composition represented by TifCrgAlh(BxCyNz) and, when f, g, h, x, y, and z in the composition represent atomic ratios, satisfying the expressions 0 < f, 0.05 < g, 0.25 < f+g £ 0.6, 0.4 < h < 0.75, 0 < x < 0.1, 0 < y < 0.3, f+g+h = 1, and x+y+z = 1 ; and, the A layer is laminated on the B layer with an intermediate layer not more than 0.5 mih in thickness interposed therebetween or without an intermediate layer, the thickness of the A layer is 0.5 to 5.0 mih, and the thickness of the B layer is 0.05 to 3.0 mih.

[0018] By specifying the component composition of each of the A layer and the B layer in such a configuration, the A layer comes to be a film having a high oxidation resistance and a high hardness and being excellent in wear resistance and the B layer comes to be a film having a high toughness and being excellent in oxidation resistance. Further, by forming the A layer having a prescribed thickness on the B layer having a prescribed thickness, the hardness of the film is enhanced and the wear resistance improves.

Furthermore, when an intermediate layer having a thickness of not more than 0.5 mih is formed, the crystal consistency of a hard film improves, the adhesiveness between the A layer and the B layer improves, and the wear resistance improves further.

[0019] Further, in a second hard film coated member according to the present invention, it is preferable that: the hard film has an intermediate layer not more than 0.5 mih in thickness between the A layer and the B layer; and the intermediate layer is formed by alternately laminating layers having the same composition as the A layer and layers having the same composition as the B layer.

[0020] By such a configuration, when an intermediate layer not more than 0.5 mih in thickness is formed, the intermediate layer can be formed easily by using two kinds of layers having the same compositions as the A layer and the B layer.

[0021] Further, in a second hard film coated member according to the present invention, it is preferable that the integrated intensity I (200) of a diffraction peak from a (200) plane is not less than twice the integrated intensity I (111) of a diffraction peak from a (111) plane when the hard film is measured through X-ray diffraction by a Q-2Q method. Furthermore, it is preferable that the FWHM of a diffraction peak from a (200) plane is not less than 1 ° when the hard film is measured through X-ray diffraction by a Q-2Q method.

By such a configuration, the wear resistance of the film improves further.

[0022] A method for forming a hard film in a second hard film coated member according to the present invention is characterized by depositing the hard film by an arc ion plating method or a sputtering method. Further in the case of specifying the relationship of the integrated intensities of the diffraction peaks as stated above, the bias voltage applied to the substrate is set at a negative voltage of 70 V or more in absolute value when the A layer and the B layer are deposited by an arc ion plating method or a sputtering method or when the A layer, the B layer, and the intermediate layer are deposited by an arc ion plating method or a sputtering method in the case of forming the intermediate layer. Further, in the case of specifying the FWHM to a prescribed value, the bias voltage applied to the substrate is set at a negative voltage of 130 V or more in absolute value when the A layer is deposited by an arc ion plating method or a sputtering method.

[0023] By depositing a film by an arc ion plating method or a sputtering method, it is possible to control the structure of the film accurately. Further in the case of forming the A layer, the B layer, and the intermediate layer, by setting the bias voltage applied to the substrate at a negative voltage of 70 V or more in absolute value when the intermediate layer is formed, the integrated intensity I (200) of a diffraction peak from a (200) plane comes to be not less than twice the integrated intensity I (111) of a diffraction peak from a (111) plane when the film is measured through X-ray diffraction by a Q-2Q method. Furthermore, by setting the bias voltage applied to the substrate at a negative voltage of 130 V or more in absolute value when the A layer is formed, the FWHM of a diffraction peak from a (200) plane comes to be not less than 1° when the film is measured through X-ray diffraction by a Q-2Q method.

Effect of the invention

[0024] Each of first and second hard film coated members according to the present invention has a hard film of specific composition and structure and hence has a high hardness and is excellent in wear resistance.

Further, by a method for forming a hard film in a first or second hard film coated member, it is possible to form a hard film having a high hardness and being excellent in wear resistance on a substrate.

Brief Description of the Drawings

[0025] Fig. 1 is a sectional view showing a first hard film coated member according to the present invention.

Fig. 2 is an X-ray diffraction (XRD) graph obtained by measuring a hard film in a first hard film coated member shown in Fig. 1 through X-ray diffraction by a Q-2Q method.

Fig. 3 is a schematic view of a composite film forming device for forming a film.

Figs. 4A and 4B are sectional views showing second hard film coated members according to the present invention.

Fig. 5 is an X-ray diffraction (XRD) graph obtained by measuring a hard film in a second hard film coated member through X-ray diffraction by a Q-2Q method.

Best Mode for Carrying Out the Invention

[0026] A hard film coated member and a method for forming a hard film according to the present invention are hereunder explained in detail with reference to drawings.

[0027] «First hard film coated member» As shown in Fig. 1, a first hard film coated member 10 according to the present invention has a hard film (hereunder referred to as a film occasionally) 4 on a substrate 1. The film 4 has A layers 2 containing prescribed elements by prescribed quantities and B layers 3 containing prescribed elements by prescribed quantities. Then the A layers 2 and the B layers 3 are laminated alternately, the thickness of one unit (a lamination period) is 10 to 50 nm when a lamination structure comprising a pair of the A layer 2 and the B layer 3 is regarded as the one unit, and the film thickness of the film 4 is 1 to 5 qm. In the present embodiment, one B layer 3 is formed firstly on the substrate 1 , one A layer 2 is formed on the B layer 3, and a plurality of units are formed. Further, an underlayer (not shown in the figure) may be formed between the B layer 3 of the hard film 4 and the substrate 1. Here, “on the substrate 1” represents on one side, both sides, or the whole surface of the substrate 1 and the coated part varies in accordance with the type of a tool.

Explanations are hereunder made specifically.

[0028] As the substrate 1 , a cemented carbide alloy, an iron-base alloy having metal carbide, a cermet, a high-speed tool steel, and the like are named. The substrate 1 is not limited to the materials however and any material can be used as long as the material can be applied to a member for cutting tools such as a tip, a drill, and an end mill and tools such as a press, a forging mold, a molding die, and a punch.

[0029] The A layer 2 is a layer having a composition represented by TiaCrbAlcSidYe(BuCvNw) and, when a, b, c, d, e, u, v, and w in the composition represent atomic ratios, satisfying the expressions “0.05 < a” (in metal elements, the same shall apply hereinafter), “0.05 < b”, “0.2 < a+b < 0.55”, “0.4 < c < 0.7”, “0.02 < d < 0.2”, “0 < e < 0.1”, “0 < u < 0.1”, “0 < v < 0.3”, “a+b+c+d+e = 1”, and “u+v+w = 1”. The A layer 2 is a film having a high oxidation resistance and a high hardness and being excellent in wear resistance.

[0030] [Ti: a (0.05 < a, 0.2 < a+b < 0.55, a+b+c+d+e = 1)] [Cr: b (0.05 < b, 0.2 < a+b < 0.55, a+b+c+d+e = 1)] Ti and Cr are elements added for keeping the crystal structure of the A layer 2 to a high hardness phase. It is necessary to add Ti and Cr by not less than 0.2 in atomic ratio in total in order to exhibit the effect. On the other hand, the total of Ti and Cr must be not more than 0.55 in order to secure the addition quantities of Al, Si, and Y. Further, hardness increases by combining nitrides having different lattice constants (for example, TiN: 0.424 nm, CrN: 0.414 nm, and AIN: 0.412 nm) and the quantities of Ti and Cr must be not less than 0.05 in atomic ratio respectively in order to exhibit the effect. Consequently, the atomic ratio a of Ti and the atomic ratio b of Cr are specified in the ranges of 0.05 < a, 0.05 < b, and 0.2 < a+b < 0.55. A yet preferable range is 0.2 < a+b < 0.5.

[0031] [Al: c (0.4 < c < 0.7, a+b+c+d+e = 1)] Al is an element to improve the oxidation resistance of the A layer 2. Al must be added by not less than 0.4 in atomic ratio in order to give a high oxidation resistance to the A layer 2. On the other hand, if Al exceeds 0.7, the A layer 2 softens and the wear resistance lowers. Consequently, the atomic ratio c of Al is specified in the range of 0.4 < c < 0.7. A yet preferable range is 0.45 < c < 0.6.

[0032] [Si: d (0.02 < d < 0.2, a+b+c+d+e = 1) Si is an element to improve the oxidation resistance of the A layer 2. Si must be added by not less than 0.02 in atomic ratio in order to give a high oxidation resistance to the A layer 2. On the other hand, if Si exceeds 0.2, the A layer 2 softens and the wear resistance lowers. Consequently, the atomic ratio d of Si is specified in the range of 0.02 < d < 0.2. A yet preferable range is 0.05 < d < 0.15.

[0033] [Y: e (0 < e < 0.1, a+b+c+d+e = 1) Y is an element added when oxidation resistance is further enhanced. If Y exceeds 0.1 in atomic ratio however, the A layer 2 softens and the wear resistance lowers. Consequently, the atomic ratio e of Y is specified in the range of 0 < e < 0.1. A yet preferable range is 0.02 < e < 0.05.

[0034] [B: u, C: v, N: w (0 < u < 0.1, 0 < v < 0.3, u+v+w = 1)] B and C can harden the A layer 2 by being added. If B exceeds 0.1 in atomic ratio however, the A layer 2 comes to be amorphous and the hardness lowers. Meanwhile, if C exceeds 0.3 in atomic ratio, free C is generated in the A layer 2, the A layer 2 softens, and the oxidation resistance lowers. Consequently, B and C may be added by not more than 0.1 and not more than 0.3 in atomic ratio respectively. N plays the role of forming nitrides acting as the backbone of the film 4 in the present invention by combining with metal elements and hence must be not less than 0.6.

[0035] Since Ti, Cr, Al, Si, and N are essential components and Y, B, and C are optional components as stated above, as the composition of the A layer 2, TiCrAlSiY(BCN), TiCrAlSi(BCN), TiCrAlSiY(CN), TiCrAlSiY(BN), TiCrAlSi(CN), TiCrAlSi(BN), TiCrAlSiYN, TiCrAlSiN, etc. are named.

[0036] The B layer 3 is a layer having a composition represented by TifCrgAlh(BxCyNz) and, when f, g, h, x, y, and z in the composition represent atomic ratios, satisfying the expressions “0 < f”, “0.05 < g”, “0.25 < f+g < 0.6”, “0.4 < h < 0.75”, “0 < x < 0.1”, “0 < y < 0.3”, “f+g+h = 1”, and “x+y+z = 1”. The B layer 3 is a film having a high toughness and being excellent in oxidation resistance.

[0037] [Ti: f (0 < f, 0.25 < f+g < 0.6, f+g+h = 1)] Ti is an element added together with Cr in order to secure the toughness of the B layer 3. It is necessary to add Ti and Cr by 0.25 or more in atomic ratio in total in order to exhibit the effect. On the other hand, if they exceed 0.6 in total, Al reduces relatively and the oxidation resistance lowers. Consequently, the expression 0.25 < f+g £ 0.6 should be satisfied. A yet preferable range is 0.3 < f+g < 0.5. Here, the B layer 3 is not necessarily so hardened as the A layer 2 and hence Ti may be 0.

When only Cr is added without the addition of Ti, namely when the B layer is CrgAlh(BxCyNz), since the hardness does not change from the case of containing Ti but Cr improves the oxidation resistance more than Ti, the wear resistance improves in dry high-speed cutting.

[0038] [Cr: g (0.05 < g, 0.25 < f+g < 0.6, f+g+h = 1)] Cr is an element added in order to secure the oxygen resistance and toughness of the B layer 3. Cr must be added by not less than 0.05 in atomic ratio in order to exhibit the effect of securing the oxidation resistance. Further, it is necessary to add Ti and Cr by 0.25 or more in atomic ratio in total in order to exhibit the effect of securing the toughness. On the other hand, if they exceed 0.6 in total, A1 reduces relatively and the oxidation resistance lowers. Consequently, the atomic ratio g of Cr is specified in the ranges of 0.05 < g and 0.25 < f+g < 0.6. A yet preferable range is 0.3 < f+g < 0.5.

[0039] [Al: h (0.4 < h < 0.75, f+g+h = 1)] With regard to the B layer 3 too, Al must be added by not less than 0.4 in atomic ratio in order to give a certain degree of oxidation resistance. On the other hand, if Al exceeds 0.75, the B layer 3 softens and the wear resistance lowers. Consequently, the atomic ratio h of Al is specified in the range of 0.4 < h < 0.75. A yet preferable range is 0.5 < h < 0.7.

[0040] [B: x, C: y, N: z (0 < x < 0.1, 0 < y < 0.3, x+y+z = 1)] B and C can harden the B layer 3 by being added. If B exceeds 0.1 in atomic ratio however, the B layer 3 comes to be amorphous and the hardness lowers. Meanwhile, if C exceeds 0.3 in atomic ratio, free C is generated in the B layer 3, the B layer 3 softens, and the oxidation resistance lowers. Consequently, B and C may be added by not more than 0.1 and 0.3 in atomic ratio respectively. N plays the role of forming nitrides acting as the backbone of the film 4 in the present invention by combining with metal elements and hence must be not less than 0.6.

[0041] Since Cr, Al, and N are essential components and Ti, B, and C are optional components as stated above, as the composition of the B layer 3, TiCrAl(BCN), CrAl(BCN), TiCrAl(CN), TiCrAl(BN), CrAl(CN), CrAl(BN), TiCrAIN, CrAIN, etc. are named.

[0042] Lamination structuro [Thickness of one unit: 10 to 50 nm] When the thickness of one unit (namely, the lamination period) of a lamination structure comprising one A layer 2 and one B layer 3 is in the range of 10 to 50 nm, the hardness of the film 4 increases and the wear resistance improves. As stated above, even in the case of specifying the compositions of the A layer 2 and the B layer 3, if the thickness of one unit is less than 10 nm or exceeds 50 nm, the wear resistance of the film 4 does not improve. Consequently, the thickness of one unit is set at 10 to 50 nm and yet preferably 20 to 40 nm. Here, one unit (a lamination period) means for example not only a pair of one A layer 2 and one B layer 3 formed tightly on the A layer 2 but also a pair of one A layer 2 and one B layer 3 formed tightly under the A layer 2. Consequently, the thickness of one unit is set at 10 to 50 nm in the combination of one A layer 2 and one B layer 3 either on or under the A layer 2.

[0043] [Thickness of film: 1 to 5 qm] With regard to the thickness of the film 4 (namely the total thickness), the effect of improving the wear resistance is small when the thickness is less than 1 qm. On the other hand, if the thickness exceeds 5 qm, the film 4 peels off the substrate 1 by residual compression stress intrinsic to a film deposited by a PVD (Physical Vapor Deposition) method. Consequently, the thickness of the film 4 is set at 1 to 5 qm.

[0044] [Others] The thickness ratio of one A layer 2 and one B layer 3 is about 1 : 1 as a guide but the performance such as hardness and wear resistance is scarcely affected even when the ratio varies in the range of about 1 : 5 to 5 : 1. If the ratio exceeds the range of 1 : 5 to 5 : 1 however, the performance is likely to lower. Consequently, the thickness ratio of one A layer 2 and one B layer 3 is preferably in the range of 1 : 5 to 5 : 1. A yet preferable range is 1 : 3 to 3 : 1. Although the first layer on the substrate 1, namely the layer sticking to the substrate 1, is one B layer 3 and one A layer 2 is laminated on the B layer 3 here, the sequence of the lamination of one A layer 2 and one B layer 3 is not particularly specified. Nevertheless, it is preferable that the first layer on the substrate 1 is one B layer 3 excellent in toughness and adhesiveness. Here, the numbers of the A layers 2 and the B layers 3 may be either identical or different from each other.

[0045] In a first hard film coated member 10, it is preferable that the integrated intensity I (200) of a diffraction peak from a (200) plane is not less than twice the integrated intensity I (111) of a diffraction peak from a (111) plane (namely I (111) x 2 < I (200)) when the hard film 4 is measured through X-ray diffraction by a Q-2Q method. Further, in the first hard film coated member 10, it is preferable that the FWHM of a diffraction peak from a (200) plane is not less than 0.7° when the hard film 4 is measured through X-ray diffraction by a Q-2Q method.

[0046] The control can be carried out by setting a bias voltage applied to the substrate 1 at a negative voltage of 130 V or more in absolute value when the film 4 is formed as it will be described later. That is, by setting the bias voltage at - 130 V or less, the integrated intensities of the diffraction peaks when the film 4 is measured through X-ray diffraction by a Q-2Q method can take the aforementioned relationship and the FWHM of the diffraction peak can take the aforementioned value.

[0047] [Preferred orientation (relationship of integrated intensities): I (111) x 2 < I (200)] The intensity ratio of diffraction peaks, namely preferred orientation, depends on a bias voltage applied to the substrate 1 when a film is formed. The (200) orientation comes to be predominant as the bias voltage increases and in particular the (200) plane is excellent in wear resistance. Then in the intensity ratio acting as the index, when the intensity of (200) is not less than twice of the intensity of (111), the wear resistance improves. Yet preferably, the intensity of (200) is not less than three times of the intensity of (111) .

[0048] [FWHM: not less than 0.7°] Not only orientation but also the crystalline state of the film 4 varies in accordance with the value of bias voltage applied to the substrate 1. More precisely, the crystal grain size of the film 4 varies and the FWHM of a (200) plane diffraction peak observed more strongly can be used as the index. When the FWHM of a diffraction peak is not less than 0.7°, the wear resistance improves further. Yet preferably, the FWHM of a diffraction peak is not less than 0.9°. The FWHM of a diffraction peak tends to increase in the region where a bias voltage is not more than -130 V but the increment is saturated in the vicinity of 2°.

[0049] Measurement through X-ray diffraction can be carried out under the following conditions for example; used apparatus: RINT-ULTIMA PC made by Rigaku Corporation, measuring method: Q-2Q, X-ray source: Cuka (graphite monochromator used), excitation voltage-current: 40 kV - 40 mA, divergence slit: 1 °, divergence longitudinal restriction slit: 10.00 mm, scattering slit: 1°, light-receiving slit: 0.15 mm, and monochrome light-receiving slit: not used.

[0050] When a multilayer film (15 nm each, the thickness of one unit being 30 nm, and the total thickness being 3 mih) comprising A layers 2 of (Ti0.2Cr0.2A10.55Si0.03 Y0.02)N and B layers 3 of (Ti0.25Cr0. 1 A10.65)N is formed by setting the bias voltage applied to a substrate 1 at - 150 V, an X-ray diffraction (XRD) graph shown in Fig. 2 is obtained. The integrated intensity and FWHM of each diffraction peak can be computed from the XRD graph (raw data) by using spreadsheet software IgorPro for example. More specifically, each value is computed by using Multi-peak fit package of the software and by carrying out fitting with a Voigt function as the peak shape. Since the diffraction peak of a substrate is also detected in the raw data during fitting, the diffraction components of the substrate and the film are also separated from each other (the substrate component is shown by a thick line (the part shown with the symbol M) in the figure).

[0051] «Method for forming hard film in first hard film coated member» A hard film 4 is deposited by an arc ion plating method or a sputtering method.

[0052] As a method for depositing a film, an arc ion plating (AIP) method or a sputtering method, which makes use of a solid evaporation source, is suitable for accurately controlling the compositions of layers, such as an A layer 2 and a B layer 3, containing many elements. Of those, the AIP method is particularly recommendable because the ionization rate is high during the evaporation of target atoms and a den se film can be formed by bias voltage applied to a substrate.

[0053] Here, in the case of obtaining the preferred orientation of a film and the FWHM of a diffraction peak satisfying the above conditions, the bias voltage applied to a substrate has to be a negative voltage of not less than 130 V in absolute value (the bias voltage is not more than - 130 V) when the film is deposited by an arc ion plating method or a sputtering method. By depositing a film with a bias voltage of not more than - 130 V, the integrated intensity ratio satisfies the expression I (111) x 2 < I (200) and the FWHM is 0.7° or more when the film is measured through X-ray diffraction by a Q-2Q method as stated above. Yet preferably, the bias voltage is - 140 V or lower. Here, if the bias voltage reduces to an excessively low negative value, the heating of the substrate during film forming and the deterioration of a film forming rate are caused and hence a preferable lower limit is -250 V.

[0054] That is, in order to produce a first hard film coated member 10 by forming a film 4 on a substrate 1, firstly the substrate 1 of a prescribed size is prepared if necessary by applying ultrasonic degreasing (substrate preparation process). Successively, after the substrate 1 is introduced into a film forming device, the substrate 1 is maintained at a prescribed temperature of 500°C to 550°C (substrate heating process) and the film 4 is deposited on the substrate by an arc ion plating or sputtering method (film forming process). In this way, a first hard film coated member 10 having prescribed composition and structure can be produced.

[0055] Explanations are made hereunder in reference to Fig. 3 in the case of using a composite film forming device as an example of a method for forming a film on a substrate 1 but the film forming method is not limited to the case.

As shown in Fig. 3, a composite film forming device 100 has : a chamber 13 including an exhaust port 11 for evacuation and gas supply ports 12 to supply a film forming gas and a rare gas; arc power supplies 15 coupled to arc evaporation sources 14; sputter power supplies 17 coupled to sputter evaporation sources 16; support tables 19 on a substrate stage 18 to support a processed material (not shown in the figure) to be coated with a film; and a bias power supply 20 to apply a negative bias voltage to the processed material through the support tables 19 between the support tables 19 and the chamber 13. Further, the composite film forming device 100 has heaters 21, a DC power supply 42 for discharge, an AC power supply 23 for filament heating, etc.

Here, arc ion plating (AIP) evaporation can be carried out by using the arc evaporation sources 14 and unbalanced magnetron sputtering (UBM) evaporation can be carried out by using the sputter evaporation sources 16.

[0056] Firstly, a target (not shown in the figure) of an alloy or a metal is attached to a cathode (not shown in the figure) of the composite film forming device 100, further a substrate 1 is attached as a processed material (not shown in the figure) onto a support table 19 on the rotating substrate stage 18, and the interior of the chamber 13 is vacuated (air is exhausted to 5x10 Pa or less) into a vacuum state. Successively, the processed material is heated to a temperature of about 500°C with the heaters 21 in the chamber 13 and etching by Ar ions is applied for 5 minutes with an ion source through thermal electron emission from a filament. Successively, arc ion plating is applied by the arc evaporation sources 14 with a target of 100 ihihf at an arc current of 150 A in an N2 atmosphere of a total pressure of 4 Pa or in an atmosphere where a gas containing carbon is added to an N2 gas when carbon is contained. A target containing B (boron) is used when B is contained.

[0057] Further, it is possible to form a laminated film by attaching targets having different compositions to a plurality of evaporation sources, mounting a processed material on a rotating support table 19, and rotating them during film forming. The processed material on the support table 19 passes through alternately in front of the evaporation sources to which the targets having different compositions are attached in accordance with the rotation of the substrate stage 18 and it is possible to form a laminated film by alternately forming films corresponding to the target compositions of the respective evaporation sources on that occasion. Furthermore, the thicknesses of an A layer 2 and a B layer 3, the thickness of one unit of the lamination structure, and the number of the units are controlled through electric powers (the quantities of evaporation) loaded to the evaporation sources and the speed and the number of rotation of the support table 19. Here, as the rotation speed of a support table 19 increases, the thickness of a layer decreases and the thickness of one unit also decreases (namely the lamination period decreases).

[0058] «Second hard film coated member» As shown in Fig. 4A, a second hard film coated member 10a according to the present invention has a hard film (hereunder referred to as a film occasionally) 4a on a substrate l a. The film 4a has an A layer 2a containing prescribed elements by prescribed quantities and a B layer 3a containing prescribed elements by prescribed quantities. Then the A layer 2a is laminated on the B layer 3a, the thickness of the A layer 2a is 0.5 to 5.0 qm, and the thickness of the B layer 3a is 0.05 to 3.0 qm. Meanwhile, as shown in Fig. 4B, a hard film coated member 10a’ having an intermediate layer 5 between the A layer 2a and the B layer 3a may be formed.

Further, an underlayer (not shown in the figure) may be formed between the B layer 3a of a hard film 4a’ and the substrate la. Here, “on the substrate l a” represents one side, both sides, or the whole surface of the substrate la and the coated part varies in accordance with the type of a tool.

Explanations are hereunder made specifically.

[0059] The substrate la, the A layer 2a, and the B layer 3a are the same as the substrate 1, the A layer 2, and the B layer 3 respectively in the first hard film coated member 10.

[0060] Lamination structuro [A layer is laminated on B layer] The B layer 3a excellent in toughness and adhesiveness is formed as the first layer on the substrate la and the A layer 2a having a high hardness and being excellent in wear resistance is formed as the outermost layer. Further, by using the B layer 3a having a cubic crystal structure, which is the same crystal structure as the A layer 2a, as the underlayer and controlling the crystal orientation of the B layer 3a to the (200) orientation, it is possible to : use the consistency at the interface between the B layer 3a and the A layer 2a; and form the A layer 2a in the state of maintaining the crystal orientation of the B layer 3a. In this way, the cutting property improves further.

[0061] [Thickness of A layer: 0.5 to 5.0 qm] With regard to the A layer 2a that is a cutting surface, the cutting service life shortens when the thickness is less than 0.5 qm and hence the thickness is set at 0.5 qm or more. A preferable thickness is 0.75 qm or more. On the other hand, if the thickness of the A layer 2a exceeds 5.0 qm, the internal stress of the A layer 2a increases and breakage (chipping) of the A layer 2a is caused, and hence the thickness is set at 5.0 qm or less. A preferable thickness is 3.0 qm or less.

[0062] [Thickness of B layer: 0.05 to 3.0 qm] With regard to the B layer 3a used as the underlayer, if the thickness is less than 0.05 mih, the adhesiveness with the substrate la is hardly secured and the orientation is hardly controlled. In addition, chipping is caused in the film. Consequently, the thickness is set at 0.05 qm or more. A preferable thickness is 0.1 qm or more. On the other hand, if the thickness of the B layer 3a exceeds 3.0 qm, the preferred orientation of the crystal shifts from (200) to more stable (111) and hence the thickness is set at 3.0 mih or less. A preferable thickness is 2.5 mih or less.

[0063] [Intermediate layer] As shown in Fig. 4B, a hard film coated member 10a’ may have an intermediate layer 5 having a thickness of 0.5 mih or less between the A layer 2a and the B layer 3a. The double-layered film can sufficiently improve wear resistance during cutting even when the intermediate layer 5 is not formed but, by forming an intermediate layer 5 having a thickness of 0.5 mih or less at the interface between the A layer 2a and the B layer 3a, the crystal consistency of the hard film 4a’ improves, the adhesiveness between the A layer 2a and the B layer 3a can improve, and resultantly the wear resistance during cutting improves further. Here, since the hardness of the intermediate layer 5 is lower than that of the A layer 2a, if the thickness of the intermediate layer 5 exceeds 0.5 mih, the intermediate layer 5 acts as the basing point of cracking and resultantly chipping is caused. Consequently, when the intermediate layer 5 is formed, the thickness of the intermediate layer 5 is set at 0.5 qm or less. The thickness is preferably 0.4 qm or less and yet preferably 0.3 qm or less. On the other hand, when the intermediate layer 5 is too thin, the effect of the intermediate layer 5 is not obtained and hence the thickness is preferably 0.05 qm or more and yet preferably 0.07 qm or more.

[0064] The intermediate layer 5 may either a monolayer or a film comprising two or more layers. Further, as shown in Fig. 4B, it is preferable that the intermediate layer 5 is formed by alternately laminating Aa layers 22 having the same composition as the A layer 2a and Bb layers 33 having the same composition as the B layer 3a. The composition of each of the layers in the intermediate layer 5 may be different from the composition of the A layer 2a or the B layer 3a but it is preferable to use layers having the same compositions from the viewpoint of the consistency of a crystal grain size and cutting the need of exchanging a target during film forming. Moreover, when two kinds of layers having different compositions are laminated alternately and a lamination structure comprising a pair of the layers is regarded as one unit, it is preferable that the thickness of the one unit is 0.005 to 0.04 qm and the intermediate layer 5 is a film comprising two or more units. By configuring the intermediate layer 5 as stated above, the wear resistance of the film 4a’ improves further. Further, by laminating two or more units, the adhesiveness between the A layer 2a and the B layer 3a improves further.

[0065] Here, although an Aa layer 22 is firstly formed on the B layer 3a, it is also possible to form a Bb layer 33 firstly on the B layer 3a. Further, the number of the Aa layers 22 and the number of the Bb layers 33 may be either identical or different. Furthermore, one unit (a lamination period) means not only a pair of an Aa layer 22 and a Bb layer 33 tightly formed on the Aa layer 22 but also a pair of an Aa layer 22 and a Bb layer 33 tightly formed under the Aa layer 22, for example. Consequently, it is preferable to set the thickness of one unit at 0.005 to 0.04 qm in the combination of an Aa layer 22 and a Bb layer 33 either on or under the Aa layer 22. Further, with regard to the film thickness ratio of the Aa layers 22 and the Bb layers 33 constituting the intermediate layer 5, the thickness of an Aa layer 22 and the thickness of a Bb layer 33 may be identical but it is possible to further improve the adhesiveness by providing a structure wherein the thickness of an Aa layer 22 comes to be larger than the thickness of a Bb layer 33 as it comes closer to the A layer 2a. Furthermore, the intermediate layer 5 may otherwise be a monolayer film having a gradient composition that approaches the composition of the A layer 2a from the side of the B layer 3a toward the side of the A layer 2a.

[0066] In a second hard film coated member 10a (10a’), it is preferable that the integrated intensity I (200) of a diffraction peak from a (200) plane is not less than twice the integrated intensity I (111) of a diffraction peak from a (111) plane (namely I (111) x 2 < I (200)) when a hard film 4a (4a’) is measured through X-ray diffraction by a0-20 method. Further, in a second hard film coated member 10a (10a’), it is preferable that the FWHM) of a diffraction peak from a (200) plane is not less than 1° when a hard film 4a (4a’) is measured through X-ray diffraction by a Q-2Q method.

[0067] The preferred orientation of the film 4a (4a’) is attained by setting a bias voltage applied to the substrate la at a negative voltage of 70 V or more in absolute value when the A layer 2a, the B layer 3a, and the intermediate layer 5 are formed as it will be described later. Further, the FWHM of a diffraction peak is attained by setting a bias voltage applied when the A layer 2a is formed at a negative voltage of 130 V or more in negative value. That is, by setting the bias voltage at -70 V or less, the integrated intensities of the diffraction peaks can take the aforementioned relationship when the hard film 4a (4a’) is measured through X-ray diffraction by a Q-2Q method. Further, by setting the bias voltage at - 130 V or less, the FWHM of the diffraction peak can take the aforementioned value when the hard film 4a (4a’) is measured through X-ray diffraction by a Q-2Q method.

[0068] [Preferred orientation (relationship of integrated intensities): I (111) x 2 < I (200)] Cutting property improves by obtaining (200) plane orientation as the preferred orientation of a cubic crystal. The preferred orientation of the A layer 2a that is the surface layer can be controlled by the preferred orientation of the B layer 3a that is the underlayer and the preferred orientation of the B layer 3a can be not (111) orientation that is intrinsically stable but (200) orientation of a cubic crystal monolayer structure by the combination of the composition of the B layer 3a and the bias voltage applied to the substrate la when the B layer 3a is formed. Orientation can be controlled by bias voltage applied to the substrate la when the B layer 3a is formed. The proportion of (200) plane orientation to (111) plane orientation increases as the absolute value of the negative bias voltage (hereunder referred to as negative bias occasionally) increases. Further, with regard to the film thickness of the B layer 3a, if the film thickness increases, stable (111) orientation is likely to be obtained and hence it is also important to control the thickness to 3.0 mih or less. Meanwhile, with regard to the A layer 2a, the A layer 2a has to be not a mixed layer comprising a hexagonal crystal structure and a cubic crystal structure but a structure comprising a cubic crystal alone in order to obtain consistency with the B layer 3a.

The change of the structure can be controlled by the bias voltage applied to the substrate la during film forming. Here, a mixed layer is formed undesirably when the absolute value of the negative bias is low. Further, the crystal orientation of the A layer 2a can be controlled by controlling the crystal orientation of the B layer 3a and the wear resistance improves when the integrated intensity of the (200) diffraction peak is not less than twice of the integrated intensity of the (111) diffraction peak as a result of the X-ray diffraction of a double-layered film as the evaluation of the (200) orientation of the double-layered film. A yet preferable ratio is two and a half times.

[0069] [FWHM: not less than 1°] With regard to the A layer 2a, the wear resistance improves as a cubic crystal monolayer structure is formed and the crystal grain size reduces. The crystal grain size of the A layer 2a can be controlled by the value of bias applied to the substrate la. The crystal grains come to be finer as the absolute value of the negative bias increases. As a specific index of the crystal grain size of a film, a FWHM of a (200) plane diffraction peak observed as a result of X-ray diffraction can be used. When the FWHM of a diffraction peak is 1.0° or more, the miniaturization of the crystal grains advances and resultantly the wear resistance improves. A yet preferable FWHM is 1.2° or more. The FWHM of a diffraction peak tends to increase in the region where the bias voltage is - 130 V or less but the increment is saturated in the vicinity of 2.5°.

[0070] Here, the measurement by X-ray diffraction can be carried out in the same manner as the X-ray diffraction in the case of the first hard film coated member 10.

[0071] Then when a double-layered film (1.5 mhi each) comprising an A layer 2a having the composition of (Ti0.2Cr0.2A10.55Si0.05)N and being formed by setting the bias voltage applied to a substrate la at - 150 V when the A layer 2a is formed and a B layer 3a having the composition of (Ti0.2Cr0.2A10.6)N and being formed by setting the bias voltage applied to the substrate la at - 100 V when the B layer 3a is formed is formed, the X-ray diffraction (XRD) graph shown in Fig. 5 is obtained. The integrated intensity and FWHM of each diffraction peak can be computed from the XRD graph (raw data) by using spreadsheet software IgorPro for example. More specifically, each value is computed by using Multi-peak fit package of the software and by carrying out fitting with a Voigt function as the peak shape. Since the diffraction peak of a substrate is also detected in the raw data during fitting, the diffraction components of the substrate and the film are also separated from each other (the substrate component is shown by a thick line (the part shown with the symbol M) in the figure).

[0072] «Method for forming hard film in second hard film coated member» A hard film 4a (4a’) can be formed in the same manner as the hard film 4 in the first hard film coated member 10.

[0073] Here with regard to the preferred orientation of the film 4a (4a’), it is necessary to set the bias voltage applied to a substrate at a negative voltage of 70 V or more in absolute value (to set the bias voltage at -70 V or less) when an intermediate layer 5 is formed in the case of forming the A layer 2a, the B layer 3a, and the intermediate layer 5 in order to control both the orientation of the B layer 3a and the crystal structure of the A layer 2a to desired conditions. By depositing a film with a bias voltage of not more than -70 V, the integrated intensity ratio satisfies the expression I (111) x 2 < I (200) when the film 4 is measured through X-ray diffraction by a Q-2Q method as stated above. A yet preferable bias voltage is -90 V or less.

Here, if the bias voltage is an excessively negative value, the substrate la is heated and the film forming rate lowers during film forming and hence a preferable lower limit is -300 V.

[0074] With regard to the FWHM of a diffraction peak, it is necessary to set the bias voltage applied to the substrate la at a negative voltage of 130 V or more in absolute value (to set the bias voltage at - 130 V or less) when an intermediate layer 5 is formed in the case of forming the A layer 2a. By forming a film at a bias voltage of - 130 V or less, a FWHM of 1.0° or more is obtained when the film 4a is measured through X-ray diffraction by a Q-2Q method as stated above. A yet preferable bias voltage is - 140 V or less. Here, if the bias voltage is an excessively negative value, the substrate la is heated and the film forming rate lowers during film forming and hence a preferable lower limit is -300 V.

[0075] That is, in order to produce a second hard film coated member 10a (10a’) by forming a film 4a on a substrate la, firstly the substrate la of a prescribed size is prepared if necessary by applying ultrasonic degreasing (substrate preparation process). Successively, after the substrate la is introduced into a film forming device, the substrate la is maintained at a prescribed temperature of 500°C to 550°C (substrate heating process) and the film 4a (4a’) is deposited on the substrate by an arc ion plating or sputtering method (film forming process). In this way, a second hard film coated member 10a (10a’) having prescribed composition and structure can be produced.

[0076] Here, the same device as used in the production of a first film coated member can be used as the film forming device and the similar operations are applied. The thicknesses of the A layer 2a, the B layer 3a, the intermediate layer 5, and the layers 22 and 33 constituting the intermediate layer 5, the thickness of one unit of the lamination structure of the intermediate layer 5, and the number of units are controlled through electric powers loaded to the evaporation sources (the quantity of evaporation) and the speed and number of rotation of the support table 19.

[0077] As explained above, in a first hard film coated member 10, it is possible to improve the wear resistance of a hard film 4 by forming a lamination structure comprising A layers 2 and B layers 3 having prescribed component compositions respectively and controlling the thickness of one unit in a prescribed range. Further, in a second hard film coated member 10a (10a’), it is possible to improve the wear resistance of a hard film 4a (4a’) by forming an A layer 2a having a prescribed component composition on a B layer 3a having a prescribed component composition and controlling the thicknesses of the A layer 2a and the B layer 3a in prescribed ranges. Furthermore, it is possible to further improve the wear resistance of a hard film 4a (4a’) by forming an intermediate layer 5 having a prescribed thickness between the A layer 2a and the B layer 3a.

[0078] As examples of a first or second hard film coated member coated with a hard film excellent in wear resistance, cutting tools such as a tip, a drill, and an end mill and tools such as a press, a forging mold, a molding die, and a punch are named. In particular, the member is suitable for a tool used for dry cutting.

Examples

[0079] Examples according to the present invention are explained hereunder. The present invention is not limited to the following examples.

In the examples, films are formed with a composite film forming device shown in Fig. 3.

[0080] «Example A: first hard film coated member» [First example] In the first example, the bias voltage during film forming is fixed to - 150 V, A layers and B layers having different compositions are formed so that the thickness of one unit (the lamination period) of a lamination structure may be 30 nm, and the influence of the film compositions on hardness and cutting property is investigated.

[0081] Firstly targets comprising alloys or metals are attached to cathodes in a composite film forming device and a cutting tool (double-blade carbide end mill, 10 ihihf) and a mirror-finished carbide test piece for hardness survey (13 mm in height, 13 mm in width, and 5 mm in thickness), those being subjected to ultrasonic degreasing in ethanol, are attached to support tables on a substrate stage. Then the interior of a chamber is vacuated (air is exhausted to 5x10 Pa or less) into a vacuum state. Successively, the processed materials are heated to a temperature of 500°C with heaters and then etching by Ar ions is applied for 5 minutes with ion sources through thermal electron emission from filaments. Successively, a film having a prescribed thickness is formed by introducing a nitrogen gas or a mixed gas produced by adding a gas containing carbon to a nitrogen gas if necessary, setting the total pressure at 4 Pa, and operating arc evaporation sources (target diameter: 100 ihihf) at a discharge current of 150 A.

[0082] Here, with regard to the forming of a laminated film, a B layer having a prescribed thickness is formed by attaching targets having the compositions of the A layers and the B layers to respective evaporation sources, rotating a substrate stage on which the substrates are mounted in the device, firstly discharging only the target for the B layer in a prescribed atmosphere of an nitrogen gas or the like independently, and applying a bias voltage of - 150 V to the substrates. Successively, a film (multilayer film) having a lamination structure formed by laminating the B layers and the A layers in this sequence is formed on the substrates so that the total thickness may be 3 qm by discharging the target for the A layers, discharging the targets for the A layers and the B layers simultaneously, and rotating the substrate stage while a bias voltage of - 150 V is applied to the substrates. The thicknesses of an A layer, a B layer, and one unit are set at about 15 nm, about 15 nm, and 30 nm, respectively.

The thicknesses of the A layer, the B layer, and one unit of the lamination structure and the number of the units are controlled by the speed and number of rotation of the support tables.

[0083] After finishing the film forming, the component compositions of the films are measured and the hardness and wear resistance of the films are evaluated. The component compositions of the metal elements in the A layers and the B layers are measured with an EPMA (Electron Probe Micro Analyzer).

[0084] The hardness of a film is evaluated by investigating the Vickers hardness of the film on a carbide end mill with a micro-Vickers hardness tester under the conditions of a load of 20 mN and a retention time of 15 seconds. A film having a hardness of 25 GPa or more is rated as good and a film having a hardness of less than 25 GPa is rated as poor.

[0085]

[0086] [Cutting test conditions] Work material: SKD61 (HRC 57) Cutting speed: 400 m/min.

Slit in depth: 5 mm Slit in radial direction: 0.6 mm Feeding: 0.06 mm/blade Evaluation condition: flank wear (at boundary) after 100 m cutting The results are shown in Tables 1 and 2. Here, in the tables, the cases not satisfying the specifications of the present invention are shown by underlining the compositions of the layers. Note that the cases not containing an essential component are not shown by underlining.

H o o > * : No Si is added to A iayer in No. 29A, no Cr is added to 8 layer in Nos. 41 A and 42A.

[0089] As shown in Tables 1 and 2, in Nos. 1A to 26A, the compositions of the films (the A layers and the B layers) fall within the ranges of the present invention and hence the hardness and the wear resistance are good.

On the other hand, in Nos. 27A to 49A, the specifications of the present invention are not satisfied and hence the hardness and the wear resistance are poor. Here, in No. 50A, the film peels off the substrate during cutting. Details are given below.

[0090] In No. 27A, the A1 quantity is lower than the lower limit in the A layer. In No. 28A, the total quantity of Ti and Cr is lower than the lower limit and the A1 quantity exceeds the upper limit in the A layer. In No. 29A, Si is not contained in the A layer. In No. 30A, the Si quantity exceeds the upper limit in the A layer. In No. 31 A, Ti and Cr are not contained and the A1 quantity exceeds the upper limit in the A layer. In No. 32A, Cr is not contained and the A1 quantity exceeds the upper limit in the A layer. In No. 33A, Ti is not contained and the A1 quantity exceeds the upper limit in the A layer.

[0091] In No. 34A, the total quantity of Ti and Cr is lower than the lower limit in the A layer. In No. 35A, the total quantity of Ti and Cr exceeds the upper limit and the A1 quantity is lower than the lower limit in the A layer. In No. 36A, the Y quantity exceeds the upper limit in the A layer. In No. 37A, the B quantity exceeds the upper limit in the A layer. In No. 38A, the C quantity exceeds the upper limit in the A layer. In No. 39A, the total quantity of Ti and Cr exceeds the upper limit and the A1 quantity is lower than the lower limit in the B layer. In 40A, the total quantity of Ti and Cr is lower than the lower limit and the A1 quantity exceeds the upper limit in the B layer. In Nos. 41A and 42A, Cr is not contained in the B layers.

[0092] In No. 43A, the total quantity of Ti and Cr exceeds the upper limit and Cr and A1 are not contained in the A layer. In No. 44A, the total quantity of Ti and Cr exceeds the upper limit and Cr and A1 are not contained in the B layer. In No. 45A, the total quantity of Ti and Cr exceeds the upper limit and A1 is not contained in the B layer. In No. 46A, Cr is not contained and the A1 quantity exceeds the upper limit in the A layer and the total quantity of Ti and Cr exceeds the upper limit and Cr and A1 are not contained in the B layer. In No. 47A, Ti is not contained and the A1 quantity exceeds the upper limit in the A layer and the total quantity of Ti and Cr exceeds the upper limit and A1 is not contained in the B layer. In No. 48A, the B quantity exceeds the upper limit in the B layer. In No. 49A, the C quantity exceeds the upper limit in the B layer. In No. 50A, Si is contained in the B layer. For the reason, the adhesiveness lowers.

[0093] [Second example] In the second example, the film compositions are not varied, the films having the thicknesses of one unit different from each other are formed, and the influence of the thickness of one unit on hardness and cutting property is investigated.

The films are formed by the same method as the first example (the conditions other than the thickness are the same as those in the first example). On this occasion, the thickness of one unit is varied for each sample.

[0094] After finishing the film forming, the component compositions of the films are measured and the hardness and wear resistance of the films are evaluated. The method for measuring component compositions and the methods for evaluating the hardness and the wear resistance are the same as those in the first example. Here, the component compositions in the films are “(Ti0.2Cr0. 15A10.55Si0. 1)N” in the A layer and “Ti0.2Cr0.2A10.6)N” in the B layer.

The results are shown in Table 3. Here, in the table, the cases of not falling within the ranges of the present invention are shown by underlining the numerals.

[0095] [Table 3] * Component composition of film A layer: (Ti0.2Cr0.15AI0.55Si0.1 )N, B layer: (Ti0.2Cr0.2AIG.6)N

[0096] As shown in Table 3, in each of Nos. 51A to 55A, the thickness of one unit of the lamination structure comprising the A layer and the B layer falls within the range of the present invention and hence the hardness and the wear resistance are good.

On the other hand, in No. 56A, the thickness of one unit is less than the lower limit and hence the hardness and the wear resistance are poor. In each of Nos. 57A and 58A, the thickness of one unit exceeds the upper limit and hence the hardness and the wear resistance are poor.

[0097] [Third example] In the third example, the film compositions and the thickness of one unit are not varied, the bias voltage during film forming is varied, and the influence of the preferred orientation of a film and the FWHM of a diffraction peak measured through X-ray diffraction on the hardness and the cutting property is investigated.

The films are formed by the same method as the first example. On this occasion, the bias voltage is varied for each sample. The thickness of one unit is set at 30 nm, the ratio of the thicknesses of the A layer and the B layer is set at 1 : 1 , and the total film thickness is set at 3 mih.

[0098] After finishing the film forming, the component compositions of the films are measured and the preferred orientation of each film and the FWHM of each diffraction peak measured through X-ray diffraction are investigated. Further, the hardness and the wear resistance of the films are evaluated. The method for measuring component compositions and the methods for evaluating the hardness and the wear resistance are the same as those in the first example. Here, the component compositions are “(Ti0.2Cr0. 15A10.55 Si0. 1)N” in the A layer and “Ti0.2Cr0.2A10.6)N” in the B layer.

[0099] With regard to the preferred orientation of each film and the FWHM of each diffraction peak, the integrated intensity ratio (described as (200)/( 111) in the table) of the diffraction peaks from a (111) plane and a (200) plane when a film is measured through X-ray diffraction by a Q-2Q method and the FWHM of the diffraction peak from a (200) plane when a film is measured through X-ray diffraction by a Q-2Q method are investigated.

The conditions of the X-ray diffraction are shown below.

[X-ray diffractometer] Used apparatus: RINT-ULTIMA PC made by Rigaku Corporation Measuring method: Q-2Q X-ray source: Cuka (graphite monochromator used) Excitation voltage-current: 40 kV - 40 mA Divergence slit: 1 ° Divergence longitudinal restriction slit: 10.00 mm Scattering slit: 1 ° Light-receiving slit: 0.15 mm Monochrome light-receiving slit: not used

[0100] Then, the integrated intensity of each diffraction peak is obtained from the XRD graph (raw data) of each sample after fitting is applied to the diffraction peak as raw data by using spreadsheet software IgorPro. More specifically, each value is computed by using Multi-peak fit package of the software and by carrying out fitting with a Voigt function as the peak shape.

The results are shown in Table 4. Here, in the table, the cases of not falling within the preferable ranges of the present invention are shown by underlining the numerals.

[0101] [Table 4] * Component composition of film A layer: (Ti02Cr0.15AI0.55SI0.1)N, B layer: (TI0.2Cr0.2AI0.6)N * Thickness of one unit: 30 nm * Ratio of thicknesses of A layer and B layer: 1 : 1 * Total film thickness: 3pm

[0102] As shown in Table 4, in each of Nos. 61A to 63A, the bias voltage is not more than - 130 V that is the preferable upper limit of the present invention and hence the effects of improving the hardness and the wear resistance are good.

On the other hand, in each of Nos. 59A and 60A, although the effects of improving the hardness and the wear resistance are good, the bias voltage exceeds -130 V that is the preferable upper limit of the present invention and hence Nos. 59A and 60A are somewhat inferior to Nos. 61A to 63A.

[0103] «Example B: second hard film coated member» [First example] In the first example, after a B layer of 1.5 pm is formed, an intermediate layer of 0.2 pm is formed by laminating two kinds of layers having the same compositions as an A layer and the B layer so that the thickness of one unit (the lamination period) of the lamination structure may be 20 nm and an A layer of 1.5 pm is formed thereon. The bias voltage at film forming is fixed to - 150 V when the A layer and the intermediate layer are formed and to - 100 V when the B layer is formed. In this way, the A and B layers having different compositions are formed and the influence of film compositions on hardness and cutting performance is investigated. Here, the intermediate layer is formed by laminating layers having the composition identical to the A layer and layers having the composition identical to the B layer in this sequence so that the thickness of each layer may be 10 nm.

[0104] Firstly targets comprising alloys or metals are attached to cathodes in a composite film forming device and a cutting tool (double-blade carbide end mill, 10 hihif) and a mirror-finished carbide test piece for hardness survey (13 mm in height, 13 mm in width, and 5 mm in thickness), those being subjected to ultrasonic degreasing in ethanol, are attached to support tables on a substrate stage. Then the interior of a chamber is vacuated (air is exhausted to 5x10 Pa or less) into a vacuum state. Successively, the processed materials are heated to a temperature of 500°C with heaters and then etching by Ar ions is applied for 5 minutes with ion sources through thermal electron emission from filaments. Successively, a film having a prescribed thickness is formed by introducing a nitrogen gas or a mixed gas produced by adding a gas containing carbon if necessary to a nitrogen gas, setting the total pressure at 4 Pa, operating arc evaporation sources (target diameter: 100 hihif) at a discharge current of 150 A, and setting the rotation speed of the substrate s at 3 rpm.

[0105] Here, with regard to the forming of a laminated film, a B layer having a prescribed thickness is formed by attaching targets having the compositions of the A layers and the B layers to respective evaporation sources, rotating a substrate stage on which the substrates are mounted in the device, firstly discharging only the target for the B layer in a prescribed atmosphere of an nitrogen gas or the like independently, and applying a bias voltage of - 100 V to the substrates. Successively, an intermediate layer of a lamination structure having a prescribed thickness comprising layers of the same composition as the A layers and layers of the same composition as the B layers is formed by discharging the target for the A layers, discharging the targets for the A layers and the B layers simultaneously in a prescribed atmosphere, and rotating the substrate stage while a bias voltage of - 150 V is applied to the substrates. Successively, an A layer having a prescribed thickness is formed on the intermediate layer by discharging only the target for the A layers independently in a prescribed atmosphere and applying a bias voltage of - 150 V to the substrates. The thicknesses of the A layer, the B layer, and one unit of the lamination structure of the intermediate layer and the number of the units are controlled by the speed and number of rotation of the support tables.

[0106] After finishing the film forming, the component compositions of the films are measured and the hardness and wear resistance of the films are evaluated.

The film compositions, the hardness, the wear resistance, and the cutting test conditions are the same as those in the first example of Example A.

The results are shown in Tables 5 and 6. Here, in the tables, the cases of not satisfying the specifications of the present invention are shown by underlining the compositions of the layers. Note that the cases of not containing an essential component are not shown by underlining.

[0107] [Table 5] because of the occurrence of chipping. Details are given below.

[0110] In No. 27B, the A1 quantity is lower than the lower limit in the A layer. In No. 28B, the total quantity of Ti and Cr is lower than the lower limit and the A1 quantity exceeds the upper limit in the A layer. In No. 29B, Si is not contained in the A layer. In No. 30B, the Si quantity exceeds the upper limit in the A layer. In No. 3 IB, Ti and Cr are not contained and the A1 quantity exceeds the upper limit in the A layer. In No. 32B, Cr is not contained and the A1 quantity exceeds the upper limit in the A layer. In No. 33B, Ti is not contained and the A1 quantity exceeds the upper limit in the A layer.

[0111] In No. 34B, the total quantity of Ti and Cr is lower than the lower limit in the A layer. In No. 35B, the total quantity of Ti and Cr exceeds the upper limit and the A1 quantity is lower than the lower limit in the A layer. In No. 36B, the Y quantity exceeds the upper limit in the A layer. In No. 37B, the B quantity exceeds the upper limit in the A layer. In No. 38B, the C quantity exceeds the upper limit in the A layer. In No. 39B, the total quantity of Ti and Cr exceeds the upper limit and the A1 quantity is lower than the lower limit in the B layer. In 40B, the total quantity of Ti and Cr is lower than the lower limit and the A1 quantity exceeds the upper limit in the B layer.

In Nos. 41B and 42B, Cr is not contained in the B layers.

[0112] In No. 43B, the total quantity of Ti and Cr exceeds the upper limit and Cr and A1 are not contained in the A layer. In No. 44B, the total quantity of Ti and Cr exceeds the upper limit and Cr and A1 are not contained in the B layer. In No. 45B, the total quantity of Ti and Cr exceeds the upper limit and A1 is not contained in the B layer. In No. 46B, Cr is not contained and the A1 quantity exceeds the upper limit in the A layer and the total quantity of Ti and Cr exceeds the upper limit and Cr and A1 are not contained in the B layer. In No. 47B, Ti is not contained and the A1 quantity exceeds the upper limit in the A layer and the total quantity of Ti and Cr exceeds the upper limit and A1 is not contained in the B layer. In No. 48B, the B quantity exceeds the upper limit in the B layer. In No. 49B, the C quantity exceeds the upper limit in the B layer. In No. 50B, Si is contained in the B layer. For the reason, chipping is caused.

[0113] [Second example] The film compositions are not varied, the thicknesses of the A layer and the B layer are fixed to 1.5 qm respectively, the thickness of the intermediate layer is varied, and the influence of the thickness of the intermediate layer on hardness and cutting property is investigated.

The films are formed by the same method as the first example (the conditions other than the intermediate layers are the same as those in the first example). Here, an intermediate layer is formed by laminating layers having the same composition as the A layer and layers having the same composition as the B layer in this sequence. Then the ratio of the thicknesses of the layers in the intermediate layer is set at 1 : 1 and the thickness of one unit is fixed to 20 nm. Note that no intermediate layer is formed in No. 51B.

[0114] After finishing the film forming, the component compositions of the films are measured and the hardness and wear resistance of the films are evaluated. The method for measuring component compositions and the methods for evaluating the hardness and the wear resistance are the same as those in the first example. Here, the component compositions in the films are “(Ti0.2Cr0. 15A10.55Si0. 1)N” in the A layer and “Ti0.2Cr0.2A10.6)N” in the B layer.

The results are shown in Table 7. Here, in the table, the case of not falling within the range of the present invention is shown by underlining the numeral.

[0115] [Table 7] * : Flank wear amount is not measurable because of the occurrence of chipping in No 56B.

* Component composition of film A layer: {Ti0.2Cr0.15AI0.55Si0.1)N, B layer: (Ti0.2Cr0.2AI0.6)N

[0116] As shown in Table 7, in Nos. 51B to 55B, the thicknesses of the intermediate layers fall within the range of the present invention and hence the hardness and the wear resistance are good. On the other hand, in No. 56B, the thickness of the intermediate layer exceeds the upper limit and hence the flank wear amount cannot be measured because of the occurrence of chipping.

[0117] [Third example] In the third example, the film compositions are not varied, the film comprising the A layer and the B layer having different thicknesses is formed for each sample, and the influence of the thicknesses of the A layer and the B layer on hardness and cutting property is investigated. Further, the preferred orientations of the films measured through X-ray diffraction are also investigated. The intermediate layers are formed here.

The films are formed by the same method as the first example (the conditions other than the film thicknesses are the same as those in the first example). On this occasion, the thicknesses of the A layer and the B layer are varied for each sample. Here, a monolayer film comprising the A layer and a monolayer film comprising the B layer are also formed as comparative examples.

[0118] After finishing the film forming, the component compositions of the films are measured and the preferred orientations of the films measured through X-ray diffraction are investigated. Further, the hardness and wear resistance of the films are evaluated. The method for measuring component compositions and the methods for evaluating the hardness and the wear resistance are the same as those in the first example. Here, the component compositions in the films are “(Ti0.2Cr0. 15A10.55 Si0. 1)N” in the A layer and “Ti0.2Cr0.2A10.6)N” in the B layer.

[0119] With regard to the preferred orientation of a film, the integrated intensity ratio (described as (200)/( 111) in the table) of the diffraction peaks from a (111) plane and a (200) plane when the film is measured through X-ray diffraction by a Q-2Q method is investigated.

Here, the conditions of X-ray diffraction and the data processing method are the same as those in the third example of Example A.

The results are shown in Table 8. Here, in the table, the cases of not falling within the ranges of the present invention and the cases of the integrated intensity ratios not falling within the preferable range of the present invention are shown by underlining the numerals.

[0120] [Table 8] * ; Rank wear amount is not measurable because of the occurrence of chipping in Nos. 67B, 69B, 70B, and 72B.

* Component composition of film A layer: (Ti0.2Cr0.15AI0.55Si0.1)N, B layer. (Ti0.2Cr0.2AIQ.6)N

[0121] As shown in Table 8, in Nos. 57B to 66B, the thicknesses of the A layers and the B layers fall within the ranges of the present invention and hence the hardness and the wear resistance are good. Further, the integrated intensity ratios fall within the preferable range of the present invention. On the other hand, no B layer is formed in No. 67B and the thickness of the B layer is lower than the lower limit in No. 69B and hence chipping is caused and the flank wear amount cannot be measured. The thickness of the B layer in No. 70B and the thickness of the A layer in No. 72B exceed the respective upper limits and hence chipping is caused and the flank wear amount cannot be measured. No A layer is formed in No. 68B and the thickness of the A layer is lower than the lower limit in No. 71 B and hence the wear resistance is poor. In Nos. 69B and 70B, the integrated intensity ratios are lower than the preferable lower limit of the present invention.

[0122] [Fourth example] In the fourth example, the film compositions and the thicknesses of the A layers and the B layers are not varied, the bias voltage is varied during film forming, and the influence of the preferred orientation of a film and the FWHM of a diffraction peak measured through X-ray diffraction on hardness and cutting performance is investigated.

The films are formed by the same method as the first example. No intermediate layer is formed however and the bias voltage is varied when the A layers are formed. That is, a B layer of 1.5 mih is formed at a bias voltage of - 100 V and then an A layer of 1.5 mih is formed thereon. On this occasion, for each sample, the bias voltage is varied when the A layer is formed.

[0123] After finishing the film forming, the component compositions of the films are measured and the preferred orientations of the films and the FWHMs of the diffraction peaks measured through X-ray diffraction are investigated. Further, the hardness and wear resistance of the films are evaluated. The method for measuring component compositions and the methods for evaluating the hardness and the wear resistance are the same as those in the first example. Here, the component compositions are “(Ti0.2Cr0. 15 A10.55 SiO. 1)N” in the A layer and “Ti0.2Cr0.2A10.6)N” in the B layer.

[0124] With regard to the preferred orientation of a film and the FWHM of a diffraction peak, the integrated intensity ratio (described as (200)/( 111) in the table) of the diffraction peaks from a (111) plane and a (200) plane when the film is measured through X-ray diffraction by a Q-2Q method and the FWHM of a diffraction peak from a (200) plane when the film is measured through X-ray diffraction by a Q-2Q method are investigated.

The conditions of X-ray diffraction are the same as those in the third example.

[0125] Then, the integrated intensity and the FWHM of each diffraction peak are obtained from the XRD graph (raw data) of each sample after fitting is applied to the diffraction peak as raw data by using spreadsheet software IgorPro. More specifically, each value is computed by using Multi-peak fit package of the software and by carrying out fitting with a Voigt function as the peak shape.

The results are shown in Table 9. Here, in the table, the cases of not falling within the preferable ranges of the present invention are shown by underlining the numerals. 226,024/2

Claims

1. [Claim 1] A hard film coated member having a hard film on a substrate, wherein : the hard film comprises A layers having a composition represented by TiaCrbAlcSidYe(B uC Nw) and, when a, b, c, d, e, u, v, and w in the composition represent atomic ratios, satisfying the expressions 0.05 < a, 0.05 < b, 0.2 < a + b < 0.55, 0.4 < c < 0.7, 0.02 < d < 0.2, 0.01 < e < 0.1, 0 < u < 0.1, 0 < v < 0.3, a+b+c+d+e = 1, and u + v + w = 1, and B layers having a composition represented by TifCrgAlh(B xCyNz) and, when f, g, h, x, y, and z in the composition represent atomic ratios, satisfying the expressions 0 < f, 0.05 < g, 0.25 < f+g < 0.6, 0.4 < h < 0.75, 0 < x < 0.1, 0 < y < 0.3, f+g + h = 1 , and x + y + z = 1 ; when the A layers and the B layers are alternately laminated and a lamination structure comprising a pair of the A layer and the B layer is considered as one unit, the thickness of the one unit is 10 to 50 nm; and the film thickness of the hard film is 1 to 5 mih.

2. [Claim 2] The hard film coated member according to Claim 1, wherein the integrated intensity I (200) of a diffraction peak from a (200) plane is 39 226,024/2 not less than twice the integrated intensity I (111) of a diffraction peak from a (111) plane when the hard film is measured through X-ray diffraction by a -2 method.

3. [Claim 3] The hard film coated member according to Claim 1 or 2, wherein the full width at half maximum (FWHM) of a diffraction peak from a (200) plane is not less than 0.7° when the hard film is measured through X-ray diffraction by a -2 method.

4. [Claim 4] A hard film coated member having a hard film on a substrate, wherein : the hard film comprises an A layer having a composition represented by TiaCrbAlcSidYe(B uC Nw) and, when a, b, c, d, e, u, v, and w in the composition represent atomic ratios, satisfying the expressions 0.05 < a, 0.05 < b, 0.2 < a + b < 0.55, 0.4 < c < 0.7, 0.02 < d < 0.2, 0 < e < 0.1, 0 < u < 0.1, 0 < v < 0.3, a+b+c+d+e = 1, and u + v + w = 1, and a B layer having a composition represented by TifCrgAlh(BxCyNz) and, when f, g, h, x, y, and z in the composition represent atomic ratios, satisfying the expressions 0 < f, 0.05 < g, 0.25 < f+g < 0.6, 0.4 < h < 0.75, 0 < x < 0.1, 0 < y < 0.3, f+g + h = 1 , and x+y+z = 1 ; and, 40 226,024/2 the A layer is laminated on the B layer with an intermediate layer not more than 0.5 mhi in thickness interposed therebetween the thickness of the A layer is 0.5 to 5.0 mhi, and the thickness of the B layer is 0.05 to 3.0 mhi.

5. [Claim 5] The hard film coated member according to Claim 4, wherein: the hard film has an intermediate layer not more than 0.5 mhi in thickness between the A layer and the B layer; and the intermediate layer is formed by alternately laminating a layer having the same composition as the A layer and a layer having the same composition as the B layer.

6. [Claim 6] The hard film coated member according to Claim 4, wherein the integrated intensity I (200) of a diffraction peak from a (200) plane is not less than twice the integrated intensity I (111) of a diffraction peak from a (111) plane when the hard film is measured through X-ray diffraction by a -2 method.

7. [Claim 7] The hard film coated member according to Claim 5, wherein the integrated intensity I (200) of a diffraction peak from a (200) plane is not less than twice the integrated intensity I (111) of a diffraction peak from a (111) plane when the hard film is measured through X-ray diffraction by a -2 method.

8. [Claim 8] The hard film coated member according to any one of Claims 4 to 7, wherein the FWHM of a diffraction peak from a (200) plane is not less than 1° when the hard film is measured through X-ray diffraction by a 2 method.

9. [Claim 9] A method for forming a hard film to produce the hard film coated member according to Claim 1, wherein the hard film is deposited by an arc ion plating method or a sputtering method.

10. [Claim 10] 41