Insert and cutting tool

Abstract

One deployment (1), showing: a boron nitride sintered body (3) having a first surface (7), a second surface (9) and a cutting edge (13) which is arranged at least on a part of a comb part (11) of the first surface (7) and the second surface (9), wherein the boron nitride sintered body (3) comprises cubic boron nitride and compressed boron nitride, wherein in a transmission X-ray diffraction of a cross-section of the boron nitride sintered body (3) perpendicular to the first surface (7), in a direction perpendicular to the first surface (7) is the X-ray intensity at the tip of a 111 diffraction peak of cubic boron nitride IcBN(111)v and the X-ray intensity at the tip of a 002 diffraction peak of compressed boron nitride IhBN(002)v, in a direction parallel to the first surface (7), the X-ray intensity at the tip of a 111 diffraction peak of cubic boron nitride IcBN(111)h and the X-ray intensity at the tip of a 002 diffraction peak of compressed boron nitride IhBN(002)h, a value for the content of compressed boron nitride, given by (IhBN(002)v+IhBN(002)h) / (IcBN(111)v+IcBN(111)h), is greater than 0.002 and less than 0.01, a cubic orientation value specified by IcBN(111)v / (IcBN(111)v+IcBN(111)h) is greater than 0.5, and an orientation value of the compressed boron nitride specified by IhBN(002)v / (IhBN(002)v+IhBN(002)h) is greater than the cubic orientation value.

Description

TECHNICAL AREA

[0001] The present disclosure relates to an insert and a cutting tool. BACKGROUND

[0002] A boron nitride sintered body has a high hardness. This boron nitride sintered body is used, for example, in inserts for crushing elements and tools, taking advantage of its characteristics. JP 5 929 655 B2 describes a boron nitride sintered body containing cubic boron nitride. JP 5 929 655 B2 also describes a complex polycrystalline substance of cubic boron nitride containing wurtzite-type boron nitride and having an orientation plane less than 0.1 with respect to the ratio I(220) / I(111) of the X-ray diffraction intensity I(220) of a (220) plane of cubic boron nitride to the X-ray diffraction intensity I(111) of a (111) plane of cubic boron nitride. In other words, 1(111) is no less than ten times the orientation plane of I(220) of the complex polycrystalline substance of cubic boron nitride. That is, one can say that the (111) plane is strongly oriented in the orientation planes.The complex polycrystalline substance cubic boron nitride is obtainable by using oriented pBN as a raw material. It is also described that, when using hexagonal boron nitride as a comparison, the wear is high and the performance as a cutting tool is poor, even when the (111) plane in the orientation planes of the cubic boron nitride is highly oriented.

[0003] Further boron nitride sintered body cutting inserts are known from e.g. JP H11 - 246 271 A and JP 2016 - 145 131 A. BRIEF EXPLANATION OF THE TASK TO BE SOLVED BY THE INVENTION

[0004] It is an object of the present invention to increase the wear resistance of an insert. MEANS OF SOLUTION

[0005] The problem is solved by an insert having the features of claim 1. The problem is further solved by a cutting tool having the features of claim 6. Further embodiments of the insert are described in the dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a perspective view showing an embodiment of inserts of the present disclosure, Fig. Figure 2 is a perspective view showing another embodiment of the inserts of the present disclosure, and Fig. Figure 3 is a front view showing an embodiment of cutting tools of the present disclosure. FORM OF EXECUTION

[0006] The boron nitride sintered bodies, inserts, and cutting tools in the present disclosure are described in detail below with reference to the drawings. These drawings, which are referenced below, show in simplified form only the main components necessary for the simplicity of the description. <Einsätze>

[0007] Fig. Figure 1 shows an embodiment of the inserts 1 of the present disclosure. In the embodiment of Fig. 1 is the insert 1 a boron nitride sintered body 3 with a polygonal shape. Fig. Figure 2 shows a further embodiment of the inserts 1 of the present disclosure. The boron nitride sintered body 3 is in the embodiment of Fig.2 is connected to a base body 5 formed from hard metal. The base body 5 and the boron nitride sintered body 1 are connected to each other to form the insert with the polygonal shape. This configuration makes it possible to reduce the proportion of the relatively expensive boron nitride sintered body 3 in the insert 1. Although the boron nitride sintered body 3 in the embodiment of Fig. 2 is arranged on one of the corner parts of the insert 1, the boron nitride sintered body 3 can be arranged on any of the corner parts.

[0008] A connecting material (not shown) containing Ti or Ag can, for example, be arranged between the boron nitride sintered body 3 and the base body 5. The boron nitride sintered body 3 and the base body 5 can be joined together with the connecting material by a conventional, known method.

[0009] In the application 1 of the present disclosure, the boron nitride sintered body 3 has a first surface 7 and a second surface 9. In the embodiments described in the Fig. 1 and Fig. As shown in Figure 2, the upper surface is the first surface 7 and the side surface is the second surface. In these embodiments, the first surface 7 is a rake surface 7 and the second surface 9 is a clearance surface 9. Hereinafter, the first surface 7 will also be referred to as the rake surface 7 and the second surface 9 as the clearance surface 9. The insert 1 has a cutting edge 13 on at least a portion of a ridge line 11 of the first surface 7 and the second surface 9.

[0010] In the insert 1 of the present disclosure, the boron nitride sintered body 3 contains cubic boron nitride and compressed boron nitride. The data are obtained by transmission X-ray diffraction at a cross-section perpendicular to the first surface 7 in the boron nitride sintered body 3. Of the data obtained, in a direction perpendicular to the first surface 7, the X-ray intensity of the 111 diffraction of the cubic boron nitride is IcBN(111)v and the X-ray intensity of the 002 diffraction of the compressed boron nitride is IhBN(002)v, and in a direction parallel to the first surface 7, the X-ray intensity of the 111 diffraction of the cubic boron nitride is IcBN(111)h and the X-ray intensity of the 002 diffraction of the compressed boron nitride is IhBN(002)h.

[0011] The identification of the planes in cubic boron nitride is based on JCPDS chart no. 01-075-6381. The identification of the planes in compressed boron nitride is based on JCPDS chart no. 18-251. The identification of the planes in hexagonal boron nitride is based on JCPDS chart no. 00-045-0893. The identification of the planes in the wurtzite-type boron nitride described later is based on JCPDS chart no. 00-049-1327.

[0012] Transmission X-ray diffraction can be performed, for example, with an arc IP X-ray diffractometer “RINT RAPID2”, manufactured by Rigaku Corporation.

[0013] (IhBN(002)v+IhBN(002)h) / (IcBN(111)v+IcBN(111)h), obtained based on each of the X-ray intensities, is a value for the compressed boron nitride content. The compressed boron nitride content value is an index that relates to the amount of compressed boron nitride contained in boron nitride sinter body 3. A higher index value indicates a higher concentration of compressed boron nitride contained in boron nitride sinter body 3. The compressed boron nitride content value is not the content itself.

[0014] In the boron nitride sintered body 3 in the inset 1 of the present disclosure, the value of the content of compressed boron nitride is greater than 0.002 and less than 0.01. That is, the boron nitride sintered body 3 in the inset 1 of the present disclosure contains the compressed boron nitride to the extent that this condition is met.

[0015] IcBN(111)v / (IcBN(111)v+IcBN(111)h), obtained based on the individual X-ray intensities above, is a cubic orientation value. If the cubic orientation value is 0.5, then one 111-plane of the cubic boron nitride is oriented in a random direction and is in an unoriented state. A larger cubic orientation value results in a greater degree that the 111-plane of the cubic boron nitride contained in the boron nitride sintered body 3 is oriented parallel to the first surface 7.

[0016] The boron nitride sintered body 3 in the insert 1 of the present disclosure has a cubic orientation value greater than 0.5. In other words, the X-ray intensity at the tip of a 111 diffraction peak of the cubic boron nitride in a vertical direction is greater than the X-ray intensity at the tip of a 111 diffraction peak of the cubic boron nitride in a parallel direction. That is to say, one can also say that the 111 plane of the cubic boron nitride is oriented along a normal direction of the first surface 7.

[0017] IhBN(002)v / (IhBN(002)v+IhBN(002)h), obtained based on the individual X-ray intensities mentioned above, is an orientation value of the compressed boron nitride. If the orientation value of the compressed boron nitride is 0.5, then one 002 plane of the compressed boron nitride is oriented in a random direction and is in an unoriented state. A larger orientation value of the compressed boron nitride results in the 002 plane of the compressed boron nitride contained in the boron nitride sintered body 3 being oriented more parallel to the first surface 7.

[0018] In the boron nitride sintered body 3 in application 1 of the present disclosure, the orientation value of the compressed boron nitride is greater than the cubic orientation value. That is, the 002 plane of the compressed boron nitride is oriented to a greater extent parallel to the first surface 7 than the 111 plane of the cubic boron nitride.

[0019] The insert 1 of the present disclosure offers excellent wear resistance due to the above configuration. This effect appears to be due to the fact that the insert 1 of the present disclosure contains a small amount of compressed boron nitride and a large number of the 002 planes of the compressed boron nitride in the first surface, such that a workpiece welded to the first surface is peeled off together with the compressed boron nitride.

[0020] The boron nitride sintered body 3 in the insert 1 of the present disclosure can have a compressed boron nitride content of 0.004–0.008. This configuration results in a high hardness of the insert 1.

[0021] The boron nitride sintered body 3 can have a cubic orientation value of 0.55 or more in the application 1 of the present disclosure. This configuration results in a high hardness of the rake face 7.

[0022] The boron nitride sintered body 3 in the insert 1 of the present disclosure can have a compressive boron nitride density of 0.8 or more. This configuration results in a long service life for the insert 1.

[0023] The boron nitride sintered body 3 can contain wurtzite-type boron nitride in the application 1 of the present disclosure. The boron nitride sintered body 3 with this configuration has a high hardness.

[0024] In the insert 1 of the present disclosure, the mean particle diameter of the cubic boron nitride can be 200 nm or less. This configuration results in high strength of the insert 1. The mean particle diameter of the cubic boron nitride can be 100 nm or less.

[0025] In the application 1 of the present disclosure, a hard coating layer (not shown) can alternatively be arranged on a surface of the boron nitride sintered body 3. <schneidwerkzeuge>

[0026] A cutting tool of the present disclosure is described below with reference to the drawings.

[0027] As in Fig. As shown in Figure 3, the cutting tool 101 of the present disclosure is, for example, a rod-shaped body extending from a first end (an upper end in Fig. 3) to a second end (a lower end in Fig. 3) extends.

[0028] As in Fig. As shown in Figure 3, the cutting tool 101 has a holder 105 extending from the first end (front end) to the second end, with a pocket 103 located on one side of the first end, and the insert 1 located in the pocket 103. The cutting tool 101 has the insert 1 and is therefore capable of performing a continuous cutting operation over a long period of time.

[0029] The pocket 103 is a component that enables the attachment of the insert 1. The pocket 103 has a seating surface that runs parallel to a lower surface of the holder 105, and a lateral retaining surface that runs perpendicular or obliquely to the seating surface. The pocket 103 opens into one side of the first end of the holder 105.

[0030] Insert 1 is arranged in pocket 103. A lower surface of insert 1 can be in direct contact with pocket 103. Alternatively, a plate (not shown) can be held between insert 1 and pocket 103.

[0031] The insert 1 is attached to the holder 105 such that at least part of a ridge line, where the rake face 7 intersects the clearance face 9 and which can be used as a cutting edge 13, projects outwards from the holder 105. In the present embodiment, the insert 1 is attached to the holder 105 by a screw 107. In particular, the insert 1 is attached to the holder 105 such that screw parts are engaged with each other by inserting the screw 107 into a through-hole 55 of the insert 1 and a front end of the screw 107 into a screw hole (not shown) formed in the pocket 103.

[0032] Suitable materials for the holder 105 include steel and cast iron. High-strength steel can be used among these materials.

[0033] The present embodiment shows and describes the cutting tool for use in a so-called turning operation. Examples of turning operations include internal diameter machining, external diameter machining, and grooving. The cutting tool is not limited to one used for turning operations. For example, the inserts 1 of the above embodiments can be used for cutting tools employed in a milling operation. <herstellungsverfahren>

[0034] The following describes a process for producing a boron nitride sintered body using the present disclosure. First, hexagonal boron nitride powder is produced, which is a raw material powder with a flat shape. One of the usual raw materials is used, the mean particle diameter of which is 0.7 µm or greater and the oxygen impurity content of which is less than 0.5% by mass. The mean particle diameter of the hexagonal boron nitride powder is defined as the mean length of the particles along the longitudinal axis of the boron nitride powder, measured using an electron microscope. The hexagonal boron nitride powder can have a mean particle diameter of 0.2–30 µm. The hexagonal boron nitride powder can be of high purity, with a purity of 99% or greater. The hexagonal boron nitride powder can contain a catalyst component used to produce cubic boron nitride powder.Alternatively, a raw material powder with a purity level of less than 99% can be used.

[0035] The cubic orientation and the orientation of the compressed boron nitride after sintering can be controlled by shaping the raw material powder using uniaxial pressing and by controlling the pressure during shaping. The hexagonal boron nitride powder, which is flat, is oriented during uniaxial pressing, and the 002 plane of the hexagonal boron nitride powder is oriented perpendicular to the direction of the pressing axis. A higher orientation of the hexagonal boron nitride powder in a molded part can be achieved by repeatedly subjecting the identical molded part to pressure using uniaxial pressing.

[0036] The boron nitride sintered body of the present disclosure can be obtained by sintering the shaped body produced according to the above method at a temperature of 1800-2200 degrees and a pressure of 8-10 GPa. The proportion of compressed boron nitride in a boron nitride sintered body can be controlled by the temperature and pressure during sintering.

[0037] Although the boron nitride sintered bodies, inserts, and cutting tools have been described above in the present disclosure, there is no intention to be limited to the foregoing embodiments. Various improvements and modifications can be made without deviating from the scope of the present disclosure. EXAMPLES

[0038] Shaped bodies were produced by uniaxial pressing of flat hexagonal boron nitride powders with mean particle diameters of 0.3 µm, 6 µm, and 16 µm, respectively, and an oxygen impurity content of 0.3 wt%. Identical hexagonal boron nitride powders were subjected to uniform pressure for the production of the shaped bodies. These shaped bodies were then sintered under the conditions shown in Table 1.

[0039] The resulting sintered bodies were then cut in a direction perpendicular to the first surface of the sintered bodies, thus producing test specimens, each with a surface intersecting the first surface at a right angle and approximately 0.5 mm thick. Using the Rigaku Corporation RINT RAPID2 arc-type IP X-ray diffractometer, the content of compressed boron nitride, the cubic orientation value, and the orientation value of the compressed boron nitride were determined based on a cross-section perpendicular to the first surface of the test specimens. Table 1 shows the individual values ​​obtained. [Table 1] Sample No. Particle diameter of the hexagonal boron nitride powder (µm) Press molding process Sintering temperature (°C) Pressure (GPa) Content value compressed boron nitride cubic orientation value guideline value of compressed boron nitride 1 0,3 uniform 2100 9 0,0038 0,49 0,50 2 6 uniform 2100 9 0,0040 0,51 0,49 3 16 uniform 2100 9 0,0043 0,52 0,51 4 0,3 uniaxial 2100 9 0,0037 0,54 0,56 5 6 uniaxial 2100 9 0,0041 0,56 0,61 6 16 uniaxial 2100 9 0,0043 0,58 0,68 7 6 uniform 2100 11 0,0000 0,50 - 8 0,3 uniaxial 2100 11 0,0000 0,55 - 9 6 uniaxial 2100 11 0,0000 0,56 - 10 16 uniaxial 2100 11 0,0000 0,59 - 11 6 uniform 1700 11 0,0040 0,51 0,46 12 0,3 uniaxial 1700 11 0,0036 0,60 0,64 13 6 uniaxial 1700 11 0,0035 0,64 0,80 14 16 uniaxial 1700 11 0,0038 0,70 1,00 15 16 uniform 2300 7,7 0,0040 0,51 0,49 16 16 uniaxial 2300 7,7 0,0040 0,54 0,51

[0040] A portion of each of the obtained sintered bodies was cut to produce an insert. A cutting test was performed using one of the insert's surfaces as the rake face. The cutting test conditions were as follows. <schnitttestbedingungen> Workpiece: Ti alloy (Ti-6Al-4V) Cutting conditions: Vc=100 m / min, f=0.1 mm / revolution, ap=0.4 mm, wet. Tool used: CNGA120408

[0041] Each of the samples Nos. 1-3, 7, 11, and 15, obtained from the molded bodies formed under uniform pressure, does not have the configuration of the boron nitride sintered body used in the present disclosure. Even when using the molded body obtained by uniaxial pressing, samples Nos. 8 to 10, with a sintering temperature of 2100°C and a sintering pressure of 11 GPa, did not contain compressed boron nitride. Sample No. 16, which used the molded body obtained by uniaxial pressing with a sintering temperature of 2300°C and a sintering pressure of 7.7 GPa, did contain compressed boron nitride, but the orientation value of the compressed boron nitride was less than the cubic orientation value.

[0042] Of the samples formed by uniaxial pressing, samples Nos. 4 to 6 and 12 to 14 exhibited a compressed boron nitride content greater than 0.002 and a cubic orientation greater than 0.5, with their respective compressed orientation values ​​being higher than their respective cubic orientation values, resulting in a long lifetime. The mean particle diameter of the cubic boron nitride in each of samples Nos. 4 to 6 and 12 to 14 was 200 nm or less. In particular, the mean particle diameter of samples No. 4 and No. 12, both of which used the raw material powder with a small mean particle diameter, was 100 nm or less.

[0043] Samples 5, 6, 12, 13, and 14, each with a cubic orientation value of 0.55 or higher, had a longer lifetime than sample 4, which had a cubic orientation value of less than 0.55. Samples 13 and 14, each with a compressed boron nitride orientation value of 0.8 or higher, had a longer lifetime than sample 12, which had a compressed boron nitride orientation value of less than 0.8.

[0044] Samples that did not meet the configuration requirements of the present disclosure had a shorter lifetime than samples Nos. 4 to 6 and 12 to 14, which each represent the use of the present disclosure. REFERENCE MARK LIST 1 deployment 3 boron nitride sinter bodies 5 basic shapes 7 Chip surface (first surface) 9 Open space (second area) 11 Ridge line 13 Cutting edge 101 Cutting tool 103 bags 105 holders< / schnitttestbedingungen> < / herstellungsverfahren> < / schneidwerkzeuge>

Claims

[1] An inset (1), showing: a boron nitride sintered body (3) having a first surface (7), a second surface (9) and a cutting edge (13) which is arranged at least on a part of a comb part (11) of the first surface (7) and the second surface (9), wherein the boron nitride sintered body (3) comprises cubic boron nitride and compressed boron nitride, wherein in a transmission X-ray diffraction of a cross-section of the boron nitride sintered body (3) perpendicular to the first surface (7), in a direction perpendicular to the first surface (7) is the X-ray intensity at the tip of a 111 diffraction peak of cubic boron nitride IcBN(111)v and the X-ray intensity at the tip of a 002 diffraction peak of compressed boron nitride IhBN(002)v, in a direction parallel to the first surface (7), the X-ray intensity at the tip of a 111 diffraction peak of cubic boron nitride IcBN(111)h and the X-ray intensity at the tip of a 002 diffraction peak of compressed boron nitride IhBN(002)h, a value for the content of compressed boron nitride, given by (IhBN(002)v+IhBN(002)h) / (IcBN(111)v+IcBN(111)h), is greater than 0.002 and less than 0.01, a cubic orientation value specified by IcBN(111)v / (IcBN(111)v+IcBN(111)h) is greater than 0.5, and an orientation value of the compressed boron nitride specified by IhBN(002)v / (IhBN(002)v+IhBN(002)h) is greater than the cubic orientation value. [2] The insert (1) according to claim 1, wherein the cubic orientation value is 0.55 or more. [3] The insert (1) according to claim 1 or 2, wherein the orientation value of the compressed boron nitride is 0.8 or more. [4] The insert (1) according to any one of claims 1 to 3, wherein the boron nitride sintered body (3) contains boron nitride of the wurtzite type. [5] The insert (1) according to any one of claims 1 to 4, wherein the mean particle diameter of the cubic boron nitride in cross-section is 200 nm or less. [6] A cutting tool (101) comprising: a holder (105) which has a length from a first end to a second end and has a pocket (103) on one side of the first end, and the insert (1) according to one of claims 1 to 5, wherein the insert (1) is arranged in the pocket (103).

Images