Sintered body with excellent impact resistance

Abstract

In response to an impact exceeding the fracture resistance of the sintered body, plastic deformation occurs prior to the onset of brittle fracture. A sintered body with improved impact resistance due to absorption, and a method for manufacturing the same, They will provide either one [Solution] It contains zirconia containing a stabilizer, and when an impact force is applied, an impact mark is formed. A sintered body characterized by having a region that is formed.

Description

Technical Field

[0001] The present disclosure relates to a sintered body having excellent impact resistance, and particularly to a sintered body having excellent impact resistance and mainly composed of zirconia.

Background Art

[0002] Compared with metal materials, ceramics have high mechanical properties and chemical stability, but are brittle materials. Therefore, when a dynamic impact at room temperature, such as dropping, is applied, a sintered body such as a zirconia ceramic mixture is liable to undergo fracture due to the generation and propagation of cracks, so-called brittle fracture. In order to prevent fracture due to such brittle fracture, improvement of fracture toughness has been studied.

[0003] For example, Patent Document 1 reports that the fracture toughness is improved by dispersing SrAlO in 4 mol% yttria-containing zirconia. Further, Patent Document 2 reports that the fracture toughness is improved and the drop resistance is improved by dispersing cubic SrNbO3 in zirconia. , O 19 x

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

[0006] In contrast, this disclosure describes how, in response to an impact exceeding the fracture resistance of the sintered body, brittle fracture occurs before the onset of brittle fracture. A sintered body with improved impact resistance due to impact absorption caused by plastic deformation. The objective is to provide at least one of the following: a product and a method for manufacturing the same. [Means for solving the problem]

[0007] The inventors investigated how to improve the impact resistance of ceramics. As a result, fracture toughness We discovered that impact resistance can be improved through a mechanism different from that of the previous method.

[0008] In other words, the present invention is as described in the claims, and the gist of this disclosure is It is as follows: [1] Contains zirconia containing a stabilizer, and when an impact force is applied, A sintered body characterized by having a region in which an impact mark is formed. [2] The sintered body according to [1] above, wherein the impact mark is a recess. [3] Stabilizer content is 3 mol% or more and 10 mol% or less, as described in [1] or [2] above. The sintered body described in [ ]. [4] The stabilizer is selected from the group consisting of yttria, calcia, magnesia and ceria. A sintered body according to any one of the above [1] to [3], wherein the number of elements is 2 or more. [5] Any of the above [1] to [4] wherein the stabilizer is yttria and ceria A sintered body as described in one of the following. [6] Any of the above [1] to [5], having an yttria content of less than 1.5 mol% A sintered body as described in any one of the following. [7] Ceria content is 2 mol% or more and 7.5 mol% or less, as described in [1] to [ A sintered body as described in any one of [6]. [8] A sintered body according to any one of [1] to [7] above, comprising alumina. [9] The intensity of the powder X-ray diffraction peak of the (220) plane of the tetragonal crystal is compared with the (004) plane of the tetragonal crystal. The above [ has a region in which the ratio of the intensity of the powder X-ray diffraction peaks on the plane is greater than 0 and less than or equal to 1.0 A sintered body as described in any one of [1] to [8].

[10] When an impact force is applied, the intensity of the powder X-ray diffraction peaks of the (220) plane of the tetragonal crystal is For each degree, the intensity of the powder X-ray diffraction peak of the (004) plane of the tetragonal crystal is greater than 1.0 and less than or equal to 10. A sintered body according to any one of the above [1] to [9], having a region which is [1].

[11] Any of the above [1] to

[10] which have a Vickers hardness of 12 GPa or less A sintered body as described above.

[12] A component comprising the sintered body described in any one of [1] to

[11] above. [Effects of the Invention]

[0009] This disclosure describes how, in the event of an impact exceeding the fracture resistance of a sintered body, plasticity occurs prior to the occurrence of brittle fracture. A sintered body with improved impact resistance due to shock absorption caused by deformation, and its manufacturing process We can provide at least one of the manufacturing methods. [Brief explanation of the drawing]

[0010] [Figure 1] A schematic diagram showing a ball drop test using a DuPont ball drop test machine. [Figure 2] A schematic diagram showing an example of the impact point (formation of a recess) after a ball drop test. [Figure 3] A schematic diagram showing an example of the area near the impact point of a high-hardness sintered body after a ball drop test. [Figure 4] A schematic diagram showing an example of the arrangement of measurement samples in a ball-fall test. [Figure 5] A schematic diagram showing a method for measuring the depth of impact marks. [Figure 6] A schematic diagram showing an example of the type of failure observed in a ball drop test: (a) state where failure has occurred, (b) state where failure has not occurred. [Figure 7] Appearance of the sintered body of Example 1 after the drop test [Figure 8] Appearance of impact marks formed on the sintered body of Example 1 after the drop test (magnified: 20x) [Figure 9] Appearance of the sintered body of Comparative Example 3 after the drop test (magnification: 20x) [Modes for carrying out the invention]

[0011] The sintered body of this disclosure will be described below with reference to an example of an embodiment.

[0012] The sintered body of this embodiment contains zirconia containing a stabilizer, and is also marked with an impact force. A sintered body characterized by having a region in which an impact mark is formed when applied.

[0013] The sintered body of this embodiment comprises zirconia containing a stabilizer, preferably containing a stabilizer. It is a so-called zirconia sintered body, with zirconia as the matrix (main phase). This is preferable. Because it contains a stabilizer, the sintered body of this embodiment is a partially stabilized zirconia sintered body. It can also be considered a constituent element.

[0014] The sintered body of this embodiment has a region in which an impact mark is formed when an impact force is applied. The reason why the impact resistance of the sintered body in this embodiment is improved, that is, the reason why the impact resistance is improved, In particular, the region where an impact mark is formed (hereinafter also called the "plastic deformation region") is applied. It is conceivable that the material exhibits a function of absorbing and dispersing the energy transmitted by the impact force. This ensures that, when an impact force is applied, at least plastic deformation occurs prior to the occurrence of brittle fracture. It is thought that a shape is formed, and as a result, the occurrence of brittle fracture is suppressed, and impact resistance is improved. .

[0015] The sintered body of this embodiment only needs to have a plastic deformation region in at least a part of the sintered body. In other words, any sintered body having a plastic deformation region is sufficient, but mainly from the plastic deformation region It may be a sintered body consisting of a plastic deformation region.

[0016] "Impact force" is a force that transmits energy to a sintered body, and is particularly a dynamic external force, preferably An external force exceeding the fracture resistance of the sintered body, more preferably a dynamic external force exceeding the fracture resistance of the sintered body, Furthermore, it is a dynamic external force that exerts elastic energy on the sintered body.

[0017] "When an impact force is applied" means that energy is applied to at least a part of the sintered body. This is a state in which, for example, the sintered body may come into contact with the ground due to falling, or the falling object may come into contact with the sintered body. Energy is dynamically applied to the sintered body when it comes into contact with an object. The condition can be cited as one example.

[0018] An "impact mark" is a mark left on a sintered body where an impact force has been applied, preferably by the application of an impact force. These are traces formed in a sintered body. In other words, impact marks are traces of plastic deformation that occurred in a sintered body. These are traces of plastic deformation that occurred prior to the fracture. Specifically, the nature of the impact marks is as follows: In the core (described later), recesses and uneven areas, and furthermore, along the direction in which the impact force is applied An example of a recessed area can be given.

[0019] In this embodiment, whether or not the sintered body has a plastic deformation region is determined by any method of the sintered body By applying an impact force (for example, a dynamic external force that causes the sintered body to fracture), this This can be confirmed by applying an impact force to the sintered body, and then observing the presence of depressions or indentations in the sintered body after the force has been applied. Impact as evidence of plastic deformation, such as protrusions (especially evidence of deformation that occurred prior to fracture). The presence of traces confirms that the sintered body has a region of plastic deformation. In the sintered body of this embodiment, impact marks are formed due to plastic deformation, but thereafter ( It may contain defects such as cracks that occur after the impact mark is formed. On the other hand, after the impact force is applied In cases where only defects such as cracks are present (i.e., the formation of impact marks due to plastic deformation) (When only defects are found without accompanying deformation) or when only deformation originating from the destruction is observed, such as in Hertz fracture. If so (i.e., only the deformation formed by the progression of the initial crack or other fracture) If confirmed (see dashed circle in Figure 9), it can be determined that there is no plastic deformation region. .

[0020] A preferred method for confirming the existence of a plastic deformation region is described in JIS K 5600 5-3. Using a compliant DuPont drop ball tester, a 300g weight was dropped at room temperature from a height of 35°C. One example is the drop test, in which a ball is dropped from 0 mm (hereinafter also simply referred to as the "drop test").

[0021] Figure 1 is a schematic diagram showing a ball drop test using a DuPont ball drop test machine. In the ball drop test, the measurement sample (101) had protective tape (107) attached to its back, and the circle It is placed on the sample stand (106) of the cylindrical ball drop test machine, and fixing tape (105) is attached to its side. It is fixed to the sample stage by being attached. The drop weight consists of a weight (104) and a punching mold (pong). Punch: Consists of 102, and the punching die (102) is placed on the surface of the measurement sample (101). It is placed there. The ball drop test is performed from the hitting mold to a height equivalent to the drop height (in Figure 1, the part indicated by the double arrows). This can be done by dropping a weight (104) from a corresponding height (350mm). (102) has a cylindrical shape with a spherical (hemispherical) tip. The material can be subjected to the same impact force as when a rigid ball of the same size as the spherical surface is dropped from a certain height. The weight (104) is dropped along the guides (103a, 103b) of the DuPont ball drop test machine. By doing so, a desired impact force is applied to the measurement sample (101) via the striking die (102). This can be done. Note that if a mold is not used, the spherical part (hemispherical part) of the mold is the same. A rigid ball with a diameter of 300g and a mass is dropped onto the sample from a height equivalent to the drop height. That's fine.

[0022] Figure 2 is a schematic diagram showing the appearance of the sintered body of this embodiment after the ball drop test. In this embodiment, the sintered body is subjected to an impact force by a falling weight (striking mold) in a ball drop test. It can be confirmed that an impact mark was formed in the affected area (hereinafter also referred to as the "impact point"). Figure 2 shows The impact mark indicates that a recess has been formed near the point of impact, and that it has a region of plastic deformation. This can be visually confirmed. Although not shown in the diagram, there are defects such as cracks near the recess. It is acceptable to do so. In contrast, Figure 3 is a schematic diagram showing the appearance of a conventional sintered body after a ball drop test. Yes. As shown in Figure 3, in conventional sintered bodies, the formation of impact marks at the impact point was not observed, and cracks were not found. Only defects such as these are occurring.

[0023] The presence or absence of a plastic deformation region can be determined by at least one of the following: visual observation and observation with an optical microscope, and furthermore, Visual inspection is sufficient. For observation with an optical microscope, the magnification should be 1-10 Examples include 0 times, preferably 10 to 30 times.

[0024] Although not shown in the diagram, conventional sintered bodies with high fracture toughness (for example, by the SEPB method) The measured fracture toughness value is 7 MPa·m 0.5 Sintered bodies exceeding a certain size (such as those exceeding a certain size) are tested before and after the ball drop test. There is no change in appearance, and the firing pin cannot be seen. In this case, the firing pin can be seen. Drop tests were conducted with increased drop heights, and impact tests were conducted to confirm the formation of recesses at the point of impact. By observing the formation of marks and the occurrence of defects, it is also possible to confirm the existence or non-existence of a plastic deformation region. However, in the sintered body of this embodiment, the ball drop test at a ball drop height of 350 mm The presence or absence of a plastic deformation region can be confirmed by this method.

[0025] In this embodiment, the ball drop test is performed using the DuPont method in accordance with JIS K 5600 5-3. The test can be conducted at room temperature (20-30°C) using a ball drop test machine. The conditions for the ball drop test are as follows: The following conditions can be cited. Dropping weight: (Shape) A rigid spherical ball with a diameter of 6.35 mm, or a ball with a diameter of 6.35 mm A cylindrical striking mold with a spherical tip of m. (mass) 300g Drop height: 350mm Measurement sample: A plate-like object measuring 40mm in length, 30mm in width, and 2mm in thickness, with both surfaces being... Sintered body with surface roughness Ra ≤ 0.02 μm

[0026] To prevent the sample fragments from scattering, the sample is placed on the sample stand of the ball-falling test machine and on one surface of the sample. Secure the (40mm x 30mm) surface with double-sided tape and place the sample to be measured. Apply fixing tape (protective tape) along the longitudinal direction of the main surface opposite to the surface on which the measurement sample is fixed. Attach and fix the sample to be measured (Figure 4). If you perform a ball drop test on the fixed sample to be measured, good.

[0027] The depth of the impact mark formed by the ball drop test can be defined as, for example, the thickness of the sintered body (Figure 2:203). The deepest point of the impact mark against (Figure 2:204) is greater than 0 and less than or equal to 3.5, and furthermore... One example is that it must be between 0.5 and 3. Note that the depth of the impact mark (indentation) is shown in Figure 2. (204) emphasizes the depth.

[0028] In this embodiment, the depth of the impact mark is measured using a general laser microscope (e.g., VK-95). Measurements can be taken using the 00 / VK-9510 (manufactured by Keyence Corporation). Observation magnification and The magnification is 10 to 50 times, and even 20 times, and the laser wavelength is 408 nm. This can be illustrated by the following example.

[0029] Figure 5 shows a schematic diagram illustrating the method for measuring the depth of the impact mark. The measurement is taken by passing through the center of the impact mark. A line profile (503A) is created, and the length of the deepest part (L1) is measured in the Z-axis direction. Measure. Similarly, measure a similar line profile so as to be orthogonal to the line profile. Perform (503B) and measure the length (L2) of the deepest part in the Z-axis direction. The lengths are averaged (=(L1+L2) / 2), and the resulting length is used to determine the depth of the impact mark (504 ) is the appropriate measurement condition for measuring the length of the deepest part, for example, is 0.5 μm / step. Yes, it is possible. Prior to measurement, a standard sample provided with the instrument with a known pattern length (for example, You can measure the patterned Si substrate (or similar) and adjust the accuracy of the analysis.

[0030] Analysis such as line profiling and measurement of the deepest point in the Z-axis direction is performed using a laser microscope. Analysis software included with the microscope (for example, software name: VK-H1A9VK ANALYZ) This can be done using image analysis with ER Version 3.0.1.0.

[0031] The zirconia contained in the sintered body of this embodiment contains a stabilizer. The stabilizer is zirconia It is sufficient to include elements that have the function of stabilizing nia, such as yttria (Y2O3) and ka. Two or more selected from the group consisting of lucia (CaO), magnesia (MgO), and ceria (CeO2) Preferably, it is above, more preferably containing at least yttria, calcia, It is preferable that one or more species are selected from the Magnesia and Celia groups, and that Yttria is also included. Furthermore, it is even more preferable that the material be yttria and ceria.

[0032] The stabilizer content is calculated based on the total amount of zirconia and the oxide-equivalent stabilizer, relative to the oxide equivalent. This is the total percentage (mol%) of stabilizers calculated. The stabilizer content is partially determined by the zirconia. Any amount that can be stabilized is acceptable, for example, zirconia containing yttria and ceria. The stabilizer content in sintered bodies (yttria and ceria-stabilized zirconia sintered bodies) is {( Let Y2O3 + CeO2 / (Y2O3 + CeO2 + ZrO2) be 100 (mol%). This can be determined. The stabilizer content is preferably 3 mol% to 10 mol%. It is more preferably 4 mol% to 7.5 mol%, and more preferably 4.2 mol% to 6 It is more preferably 0.2 mol% or less, and 4.5 mol% to 6.0 mol%. It is even more preferable that it be 4.6 mol% or more and 5.5 mol% or less More preferable.

[0033] If yttria is included as a stabilizer, the yttria content is less than 1.5 mol%. It is preferable that the concentration be 1.3 mol% or less, and more preferably 1.2 mol% or less. When ceria coexists with yttria, a sintered body can be obtained by simple methods such as atmospheric pressure sintering. To make it easier to obtain, the yttria content should be greater than 0 mol% and at least 0.5 mol%. Preferably, 0.6 mol% or more, more preferably 0.9 mol% or more, and even more preferably 0.9 mol% or more. It is particularly preferable that the amount be 1.0 mol% or more.

[0034] The sintered body of this embodiment only needs to satisfy the above-mentioned stabilizer content, but the stabilizer is The amount of ceria included is arbitrary. For example, the amount of ceria is 2mg. 1% to 7.5 mol%, furthermore 2.5 mol% to 6 mol%, and furthermore 3 The concentration is typically between 5 mol% and 5 mol%. In cases where calcia is included as a stabilizer... In total, the calcium content should be between 2 mol% and 7.5 mol%, and more specifically, 2.5 mol% Examples include cases where the concentration is 6 mol% or less, and also cases where magnesia is included as a stabilizer. The magnesia content should be between 2 mol% and 7.5 mol%, and more specifically, above 2 mol%. For example, it can be said that the concentration is 6 mol% or less.

[0035] The sintered body of this embodiment preferably contains ceria and yttria as stabilizing agents. In this case, the ceria content is 2 mol% or more, 3 mol% or more, or 3.5 mol It is % or more, and 6 mol% or less, 5.5 mol% or less, or 4.5 mol% or less, Furthermore, the yttria content must be 0.1 mol% or more, 0.5 mol% or more, or 0.9 mol% or less. Furthermore, the concentration must be less than 1.5 mol%, 1.3 mol% or less, or 1.15 mol% or less. This is preferable.

[0036] The content of each stabilizer is calculated based on the total amount of zirconia and the oxide-equivalent stabilizers, relative to the oxidation This represents the percentage (mol%) of each stabilizer converted to a physical equivalent. For example, yttria-stabilized zirconia. The yttria content in this case is the ratio of yttria to the total of zirconia and yttria. This is a percentage (mol%), and is calculated as {(Y2O3 / (Y2O3+ZrO2))×100(mol%) It can be determined from ). Also, the ceria content in ceria-stabilized zirconia is zi This is the percentage (mol%) of ceria relative to the total of luconia and ceria, {(CeO2 / It can be calculated from (CeO2 + ZrO2) × 100 (mol%). The yttria content in ria and ceria-stabilized zirconia sintered bodies is {Y2O3 / (Y2 It can be calculated as (O3 + CeO2 + ZrO2) × 100 (mol%). In this embodiment, ceria is preferably composed of tetravalent cerium, and more preferably trivalent cerium. It is preferable not to include it.

[0037] Because impact marks due to plastic deformation tend to occur more easily, the sintered body of this embodiment The ratio (molar ratio) of stabilizing elements other than yttrium to yttrium (Y) (hereinafter referred to as "S") Also called the "Y ratio," if the stabilizer other than yttrium is cerium (Ce), then... It is preferable that the ratio (also called the "Ce / Y ratio") is between 1.2 and 5.0. It is more preferable that it be between 1.4 and 4.5, and even more preferable that it be between 1.5 and 2.3. Preferably, it is 1.6 or more and 2.0 or less.

[0038] The sintered body of this embodiment may contain alumina (Al2O3). This allows the machine Mechanical properties, such as static strength, tend to be higher. The resulting material does not need to contain alumina, therefore the alumina content is 0% by mass or more. If mina is included, the alumina content is greater than 0% by mass and less than 30% by mass, preferably 0% by mass. It is greater than 20% by mass or less, more preferably 0.005% by mass or more and 10% by mass or less. Furthermore, the alumina content is 0% by mass or more, greater than 0% by mass, 0.5% by mass or more, or 1% by mass or more. Yes, and moreover, 20% by mass or less, 17% by mass or less, 12% by mass or less, 10% by mass or less The content should be 8% by mass or less. The alumina content is calculated as zirconia and the stabilizer oxide. , and the total amount of aluminum converted to Al2O3, It can be determined as the mass percentage of um. For example, if zirconia is used as a stabilizer... If tria and ceria are present, the alumina content is {Al2O3 / (ZrO2+Y2O It can be calculated as (3 + CeO2 + Al2O3) × 100 (mass%).

[0039] Alumina (Al2O3) has a significant impact on the mechanical properties of sintered bodies, and zirconia is attached to it. It has almost no coloring effect. Therefore, in this embodiment, alumina, i.e., a metallic element Aluminum that does not form a composite oxide with other materials is not included in the pigment.

[0040] The sintered body of this embodiment comprises zirconia containing a stabilizer, and contains a zirconia containing a stabilizer. A so-called zirconia sintered body, or partially stabilized zirconia, with zirconia as the matrix (main phase). A zirconia sintered body is preferred. A zirconia matrix containing a stabilizer is preferred. (Main phase) When this is used, the mass ratio of zirconia containing the stabilizer in the sintered body (hereinafter, Also called "zirconia content." ) is 70% by mass or more, preferably 80% by mass or more Preferably, it exceeds 90% by mass. The sintered body has a zirconia content of 100% by mass or less. If it consists only of zirconia containing a stabilizer, the mass percentage of zirconia is 100% by mass. The zirconia content is calculated as the amount of zirconia and oxide relative to the mass of the sintered body. This can be determined as the percentage of the total mass of the stabilizer when converted to oxides. For example, a sintered body. However, zirconia contains alumina, with the remainder containing yttria and ceria as stabilizers. If so, the content of zirconia containing a stabilizer is {(ZrO2+Y2O3+CeO 2) / (ZrO2+Y2O3+CeO2+Al2O3)} × 100 (mass%) It is possible.

[0041] The sintered body of this embodiment may contain unavoidable impurities such as hafnia (HfO2), however Preferably, it contains nothing other than stabilizers, zirconia, alumina, and unavoidable impurities. In this embodiment, the calculation of values ​​affected by the composition, such as the content and density of each component, is performed using Hafnia. These values ​​can be calculated by considering (HfO2) as equivalent to zirconia (ZrO2).

[0042] The sintered body of this embodiment preferably has a high density, more preferably a density corresponding to 98% or more in relative density. Particularly, when the alumina content increases, the density tends to decrease. For example, when the alumina content is 0 mass% or more and 10 mass% or less, the measured density has a lower limit of 5.85 g / cm or more or 5.90 g / cm 3 or more, and an upper limit of 6.20 3 g / cm or less, more preferably 6.10 g / cm 3 or less, even more preferably 6.00 g / cm 3 or less. 3 This can be cited as an example. Also, when the alumina content exceeds 10 mass% and is 20 mass% or less, the measured density is 5.30 g / cm or more and less than 5.85 g / cm 3 3 This can be cited as an example. When the alumina content exceeds 20 mass% and is less than 30 mass%, the measured density is 5.20 g / cm 3 or more and less than 5.30 g / cm 3 This can be cited as an example.

[0043] In this embodiment, the measured density can be obtained by the Archimedes method, and it is a value obtained as the mass obtained by mass measurement with respect to the volume obtained by the Archimedes method.

[0044] The crystal phase of zirconia in the sintered body of this embodiment preferably contains at least tetragonal phase, and may be composed of tetragonal phase and at least one of cubic phase and monoclinic phase.

[0045] The sintered body of this embodiment has a ratio of the intensity of the powder X-ray diffraction peak of the (004) plane of the tetragonal phase to the intensity of the powder X-ray diffraction peak of the (220) plane of the tetragonal phase (hereinafter, "I (004) / (22 0) ​This is also called the "random orientation region." It is preferable that it has ( ), and more preferably that it consists of a random orientation region. Square Crystal's (220) plane (hereinafter, "T 220 It is also called ". ) and the (004) plane of the tetragonal crystal (hereinafter, "T 004 It is also called ). ) are crystal planes that are perpendicular to each other. Such I (004) / (220) Having a region such that plastic deformation occurs when an impact force is applied. This is considered a sufficient condition for the random orientation region. (004) / (220) teeth Preferably, it is 0.1 or more and 0.7 or less, and more preferably 0.2 or more and 0.6 or less. preferable.

[0046] When the sintered body of this embodiment absorbs or disperses energy due to the application of impact force, plasticity Changes in crystal orientation can occur in the deformation region. For example, when an impact force is applied... After the application of impact force, the orientation of the crystals in the plastic deformation region increases, and furthermore, the impact force If T is applied, 220 T 004 Powder X The region where the intensity of the linear diffraction peak is greater than 1.0 and less than or equal to 10 (hereinafter also referred to as the "highly oriented region") .) is one example of having I in the highly oriented region. (004) / (220) 1. It is preferable that it be between 5 and 8.0, and more preferably between 3.0 and 5.0. stomach.

[0047] In this embodiment, the powder X-ray diffraction pattern (X-ray diffraction pattern) of the sintered body is generally Crystalline analysis X-ray diffractometer (e.g., instrument name: X'pert PRO MPD, Spect It can be measured using a device manufactured by Riss.

[0048] The following conditions can be used as measurement conditions. Radiation source: CuKα radiation (λ=1.5405Å) Tube voltage: 45kV Tube current: 40mA High-speed detector: X'Celerator + Ni filter Micro-optical system: Monocapillary, 0.1mm diameter Measurement angle: 70~80° Goniometer: Radius 240mm

[0049] In the above measurement, T 004 The diffraction intensity has a peak top at 2θ = 72.5 ± 1°. The diffraction intensity (area intensity) of the XRD peak is T 220 The diffraction intensity is 2θ = 74 ± 1° The diffraction intensity (area intensity) of the XRD peak having the peak top was confirmed as follows: It can be done.

[0050] The shape of the sintered body in this embodiment may be, for example, spherical, substantially spherical, elliptical, disc-shaped, cylindrical, or cubic. At least one of the following is selected from the group consisting of solid, rectangular, polyhedral, and nearly polyhedral shapes. Furthermore, it can be any shape that achieves the intended purpose, such as for various uses.

[0051] The sintered body of this embodiment preferably has a ball drop strength of 1 J or more, more preferably 1.5 J or more. It seems so. Ball drop strength is one indicator of impact resistance, and the higher this value, the higher the impact resistance. The drop strength of the sintered body is, for example, 10J or less, 5J or less, or 4J or less. The combination can be used as an example.

[0052] In this embodiment, the drop strength is determined by dropping a weight onto the sintered body from a predetermined drop height, and This is the energy imparted to the sintered body by the falling weight when the sintered body fractures. The falling ball strength is... It can be calculated using the formula below, and preferably the value at a sample thickness of 2 mm.

[0053] Falling ball force (J) = Mass of falling weight (g) × Falling height (mm) × Gravitational acceleration (m / s²) 2 ) The acceleration due to gravity is 9.8 m / s². 2 You can use this.

[0054] The drop strength is the same as the drop test described above, except that the drop height is set to any height shown below. It can be measured by various methods. Falling ball height: 50-500mm

[0055] Fracture is determined when the sample being measured is divided into two or more parts. This is possible (Figure 6(a)). On the other hand, if a crack occurs that does not extend from one end to the other ( Figure 6(b)) can be assumed to show no damage. Ball drop test at a specific drop height. If no damage occurs, the drop height will be increased in 50mm increments up to 500mm until damage occurs. The ball drop test can then be repeated by raising the height and performing the same visual observation. Therefore, for measurement samples that did not show fracture in the drop test from a height of 500 mm, Therefore, the drop force should be set to >5J (greater than 5J).

[0056] The sintered body of this embodiment does not improve impact resistance due to increased hardness, but rather due to plastic deformation. It is preferable to demonstrate improved impact resistance due to the tendency for plastic deformation to occur more easily. The Vickers hardness (Hv) of the sintered body in this embodiment is preferably 12 GPa or less, and 11 GPa. a or less is more preferable, and 10 GPa or less is even more preferable.

[0057] In this embodiment, Vickers hardness is determined by a method in accordance with JIS R1610:2003. It can be measured by the following. The following conditions are examples of conditions for measuring Vickers hardness. Cut. Measurement sample: (Sample thickness) 1.5±0.5mm (Measured surface roughness) Ra ≤ 0.02 μm Measured load: 10 kgf

[0058] The measurement is performed using a standard Vickers tester equipped with a diamond square pyramidal indenter (for example) This can be done using an MV-1 (manufactured by Matsuzawa Co., Ltd.). The measurement is performed by statically measuring the indenter. The object is pressed into the surface of the sample, and the diagonal length of the indentation formed on the sample surface is measured visually. Using the diagonal lengths, the Vickers hardness can be calculated from the following formula. Hv=F / {d 2 / 2sin(α / 2)}

[0059] In the above formula, Hv is the Vickers hardness (GPa), F is the measured load (10 kgf), and d is the diagonal length of the indentation mark (mm), and α is the angle of the indenter facing the other side (136°).

[0060] In this embodiment, fracture toughness can be exemplified as an indicator of the fracture resistance of the sintered body. The breakdown value is measured by a method conforming to the SEPB method specified in JIS R 1607. Fracture toughness value (MPa·m) 0.5 ) The fracture toughness value was measured with a support distance of 30 mm. The procedure was performed using a columnar sintered body sample with a width of 4 mm and a thickness of 3 mm, and the average value of 10 measurements was taken. This can be used as the fracture toughness value of the sintered body in this embodiment. Note that JIS R 1607 states that Two methods for measuring fracture toughness are specified: the IF method and the SEPB method. The IF method is a simpler method. Because it is a fixed method, there is a large variation in the measured values ​​from one measurement to the next. Therefore, the breakdown in this embodiment The absolute values ​​of fracture toughness and fracture toughness measured by the IF method cannot be directly compared.

[0061] The color tone of the sintered body in this embodiment is arbitrary, but CIE1976(L * a * b * ) in the color space Brightness L * Examples can be given of the values ​​being 80 or higher, even 85 or higher, and even 90 or higher. Furthermore, brightness L * The upper limit is 100 or less.

[0062] Lightness L * This is done in accordance with JIS Z8722, using a general spectrophotometer (e.g., CM It can be measured using a -700d (manufactured by Konica Minolta). Brightness L * Measurement conditions The following conditions apply: The measurement is performed using a black board as the background (so-called It is preferable to use a black background for measurement. Light source: F2 light source Viewing angle: 10° Measurement method: SCI

[0063] A disc-shaped sintered body with a diameter of 20 mm and a thickness of 2.7 mm was used as the measurement sample for evaluation. The surface should be mirror-polished (Ra ≤ 0.02 μm) and its color tone evaluated. A diameter of 10 mm is considered to be the effective area.

[0064] The sintered body of this embodiment, in particular, a sintered body that does not contain pigment, has the above-mentioned brightness L * Having Preferably, in this case, saturation a * and b * It tends to become smaller. For example, in this embodiment Saturation a of sintered body * and b* These are -6≦a * ≤ -2, and 10 ≤ b * ≤30 One example is...

[0065] The sintered body of this embodiment is a sintered body, particularly a sintered body of a structural material, optical material, dental material, etc. Applicable to conia sintered body applications, but not for decorative items, watch and casing covers, or other accessory uses. In addition, components that require relatively high impact resistance, such as exterior components for mobile phones and other portable electronic devices. It can be used as such.

[0066] Further preferred embodiments include the following: (1) One or more stabilizers selected from the group consisting of calcia, magnesia and ceria, and ( It contains zirconia, with the remainder being zirconia, and the stabilizer content is 2 mol% or more. 7.5 mol% or less, the yttria content is greater than 0 mol% and less than 1.5 mol%, and Furthermore, the intensity of the powder X-ray diffraction peak of the (220) plane of the tetragonal crystal, and the (004) plane of the tetragonal crystal A sintered body having a region where the intensity of the powder X-ray diffraction peak on the surface is greater than 0 and less than or equal to 1.0. (2) The sintered body according to (1) above, wherein the stabilizer is ceria. (3) The total amount of stabilizer and yttria is 4 mol% or more and 7.5 mol. A sintered body according to (1) or (2), wherein the content is 1% or less. (4) The sintered body has a positive relationship with respect to the intensity of the powder X-ray diffraction peak of the (220) plane of the tetragonal crystal. From the region where the intensity of the powder X-ray diffraction peak of the (004) plane of the gonal crystal is greater than 0 and less than or equal to 1.0. A sintered body as described in any of (1) to (3) above. <Other Embodiments> Other embodiments of the present disclosure have a region in which an impact mark is formed when an impact force is applied. This is a sintered body characterized by the following features.

[0067] Other embodiments of the present disclosure are characterized in that an impact mark is formed when an impact force is applied. It is a sintered body.

[0068] Other embodiments of this disclosure are based on the DuPont Fall Ball Test in accordance with JIS K 5600 5-3. Using the test equipment, a 300g drop weight is dropped from a height of 350mm at room temperature in a drop test. This is a sintered body characterized by the formation of recesses through experimentation.

[0069] Other embodiments of the present disclosure relate to the intensity of powder X-ray diffraction peaks of the (220) plane of a tetragonal crystal. , a region where the intensity of the powder X-ray diffraction peak of the (004) plane of the tetragonal crystal is greater than 0 and less than or equal to 1.0. The intensity of the powder X-ray diffraction peaks of the (220) plane of the tetragonal crystal is compared to the intensity of the powder X-ray diffraction peaks after an impact force is applied. The intensity of the powder X-ray diffraction peak of the (004) plane of the tetragonal crystal is greater than 1.0 and less than or equal to 10. It is a sintered body having a region.

[0070] In these embodiments, the sintered body is preferably a zirconia sintered body, and partial axle It is more preferable that the sintered body is stabilized zirconia, and that yttria and ceria stabilized zirconia It is even more preferable that the body be a sintered body, and that the yttria content is 1.0 mg. It is a yttria and ceria-stabilized zirconia sintered body containing 1% or more and less than 1.5 mol%. It would be even more preferable.

[0071] The following describes the method for manufacturing the sintered body according to this embodiment.

[0072] The sintered body of this embodiment can be manufactured in any way that satisfies the above requirements. Yes. As an example of the manufacturing method of the sintered body of this embodiment, two or more stabilizing agent sources and zirconia are used. An example of a manufacturing method is one that includes a step of sintering a molded body containing the material.

[0073] The molded body subjected to the above process (hereinafter also referred to as the "sintering process") is provided with two or more stabilizing agent sources. It is a molded body (compacted powder) containing zirconia.

[0074] The stabilizer source only needs to contain elements that act as stabilizers through sintering, such as yttria and ka. Lucia, magnesia and ceria, or their precursor yttrium (Y), One or more selected from the group of calcium (Ca), magnesium (Mg), and cerium (Ce) Any compound containing the above elements will suffice (hereinafter, stabilizers when yttria is the stabilizer) The source is also called the "yttria source," etc. The stabilizer source is yttria and ceria, or , chemical compounds containing at least one of the elements yttrium and cerium, which are precursors to these compounds Preferably a compound, containing at least one compound including yttria and yttrium. It is preferable that it be either one of the compounds containing ceria and cerium, or at least one of the compounds containing ceria and cerium. It seems so.

[0075] The yttria source is at least yttria and yttria compounds that are precursors to it. Any of the following is acceptable, selected from the group consisting of yttrium chloride, yttria, and yttrium carbonate. One or more of the following are listed, and it is preferable that they be yttria.

[0076] The ceria source is at least one of ceria and its precursor cerium compounds. For example, one or more selected from the group consisting of cerium chloride, ceria, and cerium carbonate, and salt It is preferable that it be cerium oxide.

[0077] The calcia source is at least one of calcia and calcium compounds that are precursors thereto. The group of calcium chloride, calcia, calcium carbonate, and calcium bicarbonate is acceptable. One or more are selected from the list, and it is preferable that one is calcia.

[0078] The magnesia source is at least one magnesium compound that is a precursor to magnesia. Any of the following will suffice: magnesium chloride, magnesia, magnesium carbonate, and magnesium bicarbonate. One or more elements selected from the group of magnesium are listed, and it is preferable that the element is magnesia.

[0079] The content of the stabilizer source in the molded body is equivalent to the content of the stabilizer in the target sintered body. That's all you need to do.

[0080] When a sintered body containing alumina is used, the molded body may contain an alumina source. The lumina source contains alumina (Al2O3) and its precursor, aluminum (Al). At least one of the compounds, including aluminum chloride, aluminum sulfate, and aluminum nitrate. One or more selected from the group consisting of nium, aluminum hydroxide, and alumina, and alumina It is preferable that this be the case.

[0081] The alumina source content in the molded body is equivalent to the alumina content of the target sintered body. That's all you need to do.

[0082] To improve shape stability, the molded body may contain a binder. The binder may be a ceramic. Any organic binder used in molding can be used, for example, acrylic resin, polyolefin One or more selected from the group consisting of resins, waxes, and plasticizers. The binder content and For example, the proportion of the binder to the volume of the molded article can be 25 to 65% by volume.

[0083] The shape of the molded body can be any shape appropriate to the purpose, taking into account shrinkage due to sintering. For example, spherical, nearly spherical, elliptical, disc-shaped, cylindrical, cubic, rectangular, polyhedral, and nearly polyhedral. At least one of the facet-shaped groups can be selected.

[0084] The method for manufacturing the molded body is arbitrary and may include zirconia, a stabilizing agent source, and, if necessary, aluminum. This includes mixing and molding the na source in any way. Also, zirconia and stabilizers. Alternatively, in addition to the source, or in addition to zirconia and stabilizer sources, stabilizer-containing zirconia can be used. That's fine.

[0085] When using zirconia containing a stabilizer, the stabilizer is added to the zirconia. The method of inclusion is arbitrary. For example, hydrated zirconia sol and the inclusion of the desired stabilizer. This may involve mixing it with a stabilizer source of equivalent quantity, followed by drying, calcination, and washing with water.

[0086] The mixing method is arbitrary, preferably at least one of dry mixing or wet mixing. Preferably, wet mixing is performed, and more preferably, wet mixing using a ball mill.

[0087] The molding method can be any known molding method, preferably uniaxial compression molding, isotropic compression molding, or injection molding. It is at least one selected from the group consisting of casting, extrusion, rolling granulation, and slip casting. Preferably, at least one of uniaxial compression molding and isotropic compression molding, and more preferably cold molding. It involves at least one of the following: hydrostatic pressing or uniaxial pressure molding (powder press molding).

[0088] The sintering process involves sintering the molded body to obtain a sintered body. The sintering method is arbitrary and can be atmospheric pressure sintering or pressurized sintering. Examples of known sintering methods include sintering and vacuum sintering. A preferred sintering method is atmospheric pressure sintering. Because it is simple, the sintering method is preferably atmospheric pressure sintering only. The sintered body of the embodiment can be obtained as a so-called atmospheric pressure sintered body. Atmospheric pressure sintering refers to sintering. Sometimes, sintering occurs simply by heating the molded body (or calcined body) without applying any external force. This is the method.

[0089] The conditions for atmospheric pressure sintering are a sintering temperature of 1250°C to 1600°C, preferably 13 Examples include temperatures between 00°C and 1580°C, and between 1300°C and 1560°C. The atmosphere may be at least one of an atmospheric atmosphere and an oxygen atmosphere, and the atmospheric atmosphere This is preferable. As a result, when ceria is included as a stabilizer, the ceria is tetravalent. Cerium (Ce 4+ ) consists of. [Examples]

[0090] The embodiment will be described in detail below with reference to examples. However, this embodiment is This is not limited to the examples provided. (Confirmation of the plastic deformation region) DuPont type ball drop tester conforming to JIS K 5600 5-3 (device name: H-50) The presence or absence of a plastic deformation region in the sintered body sample was confirmed by a ball drop test using a device manufactured by Toyo Seiki Co., Ltd. The test conditions are as follows. Dropping weight: (Shape) A spherical rigid ball with a diameter of 6.35 mm, i.e., a diameter of 6.35 m A cylindrical die with a spherical tip measuring m and a height of 10 mm. (Weight) 300g, made of stainless steel, 80mm wide x 20mm thick A rectangular prism-shaped weight measuring m x 30 mm in height, with a mass of 300 g. Drop height: 350mm Measurement sample: A sintered body in the shape of a plate measuring 40 mm (length) x 30 mm (width) x 2 mm (thickness), with a surface roughness of Ra ≤ 0.02 μm on both surfaces (the 40 mm x 30 mm surface; the main surface). To prevent the sample fragments from scattering, the sample is placed on the sample stand of the ball-falling test machine and on one surface of the sample. The surface (40mm x 30mm) was fixed with double-sided tape, and the sample to be measured was placed on it. Tape is applied along the longitudinal direction of the surface opposite to the fixed surface of the measurement sample, and the measurement sample is fixed in place. (Done). The mold was positioned so that the falling weight would land near the center of the fixed measurement sample, and the falling ball... The test was conducted.

[0091] (Measurement of ball drop strength) Aside from changing the height of the dropped ball, the method was the same as the dropped ball test used to confirm the plastic deformation region. The intensity of the falling ball was measured. That is, the condition of the sample to be measured was visually confirmed after the falling weight was dropped, and then measured. The drop strength at the drop height where fracture occurred in the sample was determined using the following formula. Ball impact force (J) = Mass of falling weight (g) × Height of fall (mm) × Gravitational acceleration (9.8m / ) s 2 )

[0092] Fracture is determined when the sample being measured is divided into two or more pieces. Furthermore, extremely small fragments, similar to chipping, were generated, and the measurement sample maintained its plate-like shape. The condition was not considered to be broken. No breakage occurred in the ball drop test at a specific drop height. In this case, the drop test is conducted by increasing the drop height in 50mm increments up to 500mm until destruction occurs. I repeated this. For the sample that did not show any damage in the drop test from a height of 500 mm, For convenience, the drop force was defined as >5J (greater than 5J). (Depth of impact marks) The depth of the impact mark was measured using a standard laser microscope (device name: VK-9500 / VK-9510). Measurements were taken using a KEYENCE (manufactured by Keyence Corporation) at a magnification of 20x. The measurement was taken so that the impact mark would pass through the center of the impact mark. A line profile is created, and the length of the deepest part (L1) is measured in the Z-axis direction at 0.5 μm / step. After measuring the line profile, the line profile is then measured in a similar manner so as to be orthogonal to the line profile. The file was processed and the length of the deepest point (L2) in the Z-axis direction was measured. The obtained lengths of both deepest points were then used. The average length (=(L1+L2) / 2) was used as the depth of the impact mark. (Vickers hardness) Vickers hardness is measured using a standard Vickers test with a diamond square pyramidal indenter. The procedure was performed using a machine (device name: MV-1, manufactured by Matsuzawa Corporation).

[0093] The indenter is statically pressed into the surface of the sample to be measured, and the diagonal length of the indentation formed on the surface of the sample to be measured is... The diagonal length obtained by visual measurement is used to calculate the Vickers hardness (GPa) from the above formula. They sought it. (density) The measured density of the sintered body sample was determined by the Archimedes method relative to the mass measured by mass dating. The ratio of volume (g / cm³) 3 ) was calculated as follows. (I (004) / (220) ) Crystalline phase of sintered body sample, T 004 and T 220 The diffraction intensity is measured using micro-XRD (instrument name: X Measurements were taken using 'pert PRO MPD (manufactured by Spectris).' The measurement conditions are as follows: To write down. Radiation source: CuKα radiation (λ=1.5405Å) Tube voltage: 45kV Tube current: 40mA High-speed detector: X'Celerator + Ni filter Micro-optical system: Monocapillary, 0.1mm diameter Measurement angle: 70~80° Goniometer: Radius 240mm

[0094] Regarding the impact point and areas other than the impact point in the measurement sample before testing and after confirmation of the plastic deformation region Micro-area XRD measurements were then performed. (004) / (220) The calculation was performed according to the following formula. . I (004) / (220) =(T 004 (Diffraction intensity of) / (T 220 Diffraction strength (degrees)

[0095] (Color measurement) The color tone of the sintered body sample was measured according to the method compliant with JIS Z8722. A spectrophotometer (device name: CM-700d, manufactured by Konica Minolta) was used, with a black plate on the back. Measurements were taken using a black background. The measurement conditions were as follows: Light source: F2 light source Viewing angle: 10° Measurement method: SCI

[0096] A sintered body sample with a diameter of 20 mm and a thickness of 2.7 mm was used. One surface is mirror-polished (Ra ≤ 0.02 μm), and this surface is used as the evaluation surface for color tone. The evaluation was conducted. The effective area for color evaluation was set at a diameter of 10 mm.

[0097] Example 1 A hydrolysis reaction of an aqueous solution of zirconium oxychloride yielded a hydrated zirconia sol. The ria concentration is 1.1 mol% and the ceria concentration is 3.4 mol%, And cerium chloride heptahydrate were added to and mixed with hydrated zirconia sol, respectively. After bonding, the mixture is dried in the air and then calcined in the air at 1155°C for 2 hours to stabilize the yttria and ceria. Calcined zirconia powder was obtained. The obtained calcined powder was washed with pure water and dried, and yttria-containing Yttria and ceria contain 1.1 mol% and 3.4 mol% respectively. A zirconia powder consisting of stabilized zirconia was obtained.

[0098] The obtained powder and α-alumina powder containing 5% by mass of alumina were added to pure water. This is then made into a slurry, which is then crushed into balls using 10mm diameter zirconia balls as the crushing medium. The mixture was ground and mixed in a mill for 18 hours. The slurry after grinding and mixing was dried, and 5 mass of alumina was added. It contains %, with the remainder being yttria content 1.1 mol% and ceria content 3.4 mol%. The zirconia powder of this example was obtained, consisting of yttria and ceria-stabilized zirconia.

[0099] The obtained powder was granulated into powder granules, which were then filled into a plate-shaped mold measuring 40 mm in length and 30 mm in width. Filling, uniaxial pressing at a molding pressure of 50 MPa, and cold isostatic pressing at a molding pressure of 196 MPa. A plate-shaped molded body (compacted powder) was obtained by the CIP (Cleaning Injection) process. The obtained molded body was subjected to the following conditions The material is sintered in a manner that produces a material containing 5% by mass of alumina, with the remainder being yttria with a content of 1.1 mol% and ce This example consists of yttria-ceria stabilized zirconia with a 3.4 mol% yttria-ceria content. A sintered body was obtained. The sintering conditions are shown below. Sintering method: Atmospheric pressure sintering Sintering atmosphere: Atmospheric atmosphere Sintering temperature: 1550℃ Sintering time: 2 hours

[0100] Example 2 Add cerium chloride heptahydrate to hydrated zirconia sol to achieve a ceria concentration of 3.9 mol%. Except for adding and mixing, the same method as in Example 1 was used to prepare a mixture containing 5% by mass of alumina, with the remainder being which has a yttria content of 1.1 mol% and a ceria content of 3.9 mol% of yttria- The zirconia powder of this example consisting of ceria-stabilized zirconia was obtained.

[0101] Except for using the obtained zirconia powder, in the same manner as in Example 1, 5% by mass of alumina was included, and the balance was yttria- ceria-stabilized zirconia having a yttria content of 1.1 mol% and a ceria content of 3.9 mol%. The sintered body of this example consisting of yttria-ceria-stabilized zirconia was obtained.

[0102] Example 3 Except for adding and mixing cerium chloride heptahydrate to the hydrated zirconia sol so that the ceria concentration becomes 5.0 mol%, in the same manner as in Example 1, 5% by mass of alumina was included, and the balance was yttria-ceria-stabilized zirconia having a yttria content of 1.1 mol% and a ceria content of 5.0 mol%. The zirconia powder of this example consisting of yttria- ceria-stabilized zirconia was obtained.

[0103] Except for using the obtained zirconia powder, in the same manner as in Example 1, 5% by mass of alumina was included, and the balance was yttria-ceria-stabilized zirconia having a yttria content of 1.1 mol% and a ceria content of 5.0 mol%. The sintered body of this example consisting of yttria-ceria-stabilized zirconia was obtained.

[0104] Example 4 Except for adding and mixing yttria and cerium chloride heptahydrate to the hydrated zirconia sol so that the yttria concentration becomes 0.7 mol% and the ceria concentration becomes 5.0 mol%, in the same manner as in Example 1, 5% by mass of alumina was included, and the balance was yttria- ceria-stabilized zirconia having a yttria content of 0.7 mol% and a ceria content of 5.0 mol%. The zirconia powder of this example consisting of yttria-ceria-stabilized zirconia was obtained. [[ID=四十一]] 含有量0.7mol%及びセリア含有量5.0mol%であるイットリア·セリア安定化 ジルコニアからなる本実施例のジルコニア粉末を得た。

[0105] A sintered body of this example made of alumina-containing 5% by mass, the balance being yttria-stabilized zirconia with a yttria content of 0.7 mol% and a ceria content of 5.0 mol% was obtained in the same manner as in Example 1, except that the obtained zirconia powder was used. % by mass, with the balance being yttria-stabilized zirconia having a yttria content of 0.7 mol% and a ceria content of 5.0 mol%. A sintered body of this example made of yttria-ceria-stabilized zirconia was obtained.

[0106] Example 5 Zirconia powder of this example made of yttria-ceria-stabilized zirconia containing 5% by mass of alumina, with the balance being yttria with a content of 1.0 mol% and ceria with a content of 3.6 mol% was obtained in the same manner as in Example 1, except that yttria and cerium chloride heptahydrate were added to and mixed with the hydrated zirconia sol so that the yttria concentration became 1.0 mol% and the ceria concentration became 3.6 mol%. Yttria and cerium chloride heptahydrate were added to and mixed with the hydrated zirconia sol, respectively. A sintered body of this example made of yttria-ceria-stabilized zirconia containing 5% by mass of alumina, with the balance being yttria with a content of 1.0 mol% and ceria with a content of 3.6 mol% was obtained in the same manner as in Example 1, except that the obtained zirconia powder was used. Zirconia powder of this example made of yttria-ceria-stabilized zirconia containing 5% by mass of alumina, with the balance being yttria with a content of 1.0 mol% and ceria with a content of 3.6 mol% was obtained. A sintered body of this example made of yttria-ceria-stabilized zirconia containing 5% by mass of alumina, with the balance being yttria with a content of 1.0 mol% and ceria with a content of 3.6 mol% was obtained in the same manner as in Example 1, except that the obtained zirconia powder was used.

[0107] A sintered body of this example made of yttria-ceria-stabilized zirconia containing 5% by mass of alumina, with the balance being yttria with a content of 1.0 mol% and ceria with a content of 3.6 mol% was obtained in the same manner as in Example 1, except that the obtained zirconia powder was used. % by mass, with the balance being yttria with a content of 1.0 mol% and ceria with a content of 3.6 mol%. A sintered body of this example made of yttria-ceria-stabilized zirconia was obtained.

[0108] Comparative Example 1 Zirconia powder of this comparative example made of yttria-ceria-stabilized zirconia containing 5% by mass of alumina, with the balance being yttria with a content of 1.5 mol% and ceria with a content of 3.4 mol% was obtained in the same manner as in Example 1, except that yttria was added to and mixed with the hydrated zirconia sol so that the yttria concentration became 1.5 mol%. Yttria was added to and mixed with the hydrated zirconia sol. A sintered body of this comparative example made of yttria-ceria-stabilized zirconia containing 5% by mass of alumina, with the balance being yttria with a content of 1.5 mol% and ceria with a content of 3.4 mol% was obtained in the same manner as in Example 1, except that the obtained zirconia powder was used. Zirconia powder of this comparative example made of yttria-ceria-stabilized zirconia containing 5% by mass of alumina, with the balance being yttria with a content of 1.5 mol% and ceria with a content of 3.4 mol% was obtained.

[0109] A sintered body of this comparative example made of yttria-ceria-stabilized zirconia containing 5% by mass of alumina, with the balance being yttria with a content of 1.5 mol% and ceria with a content of 3.4 mol% was obtained in the same manner as in Example 1, except that the obtained zirconia powder was used. It contains mass% of yttria and ceria, with the remainder being 1.5 mol% yttria and 3.4 mol% ceria. A sintered body of this comparative example was obtained from a certain yttria-ceria stabilized zirconia.

[0110] Comparative Example 2 The yttria concentration is 2.0 mol%, and the ceria concentration is 3.9 mol%, Yttria and cerium chloride heptahydrate were added to and mixed with hydrated zirconia sol, respectively. Except for the addition of a different compound, the method was the same as in Example 1, and the mixture contained 5% by mass of alumina with the remainder being yttria. Yttria-ceria stabilized with a content of 2.0 mol% and a ceria content of 3.9 mol%. A zirconia powder for this comparative example, consisting of zirconia, was obtained.

[0111] Alumina was prepared in the same manner as in Example 1, except that the obtained zirconia powder was used. It contains mass% of yttria and ceria, with the remainder being yttria content 2.0 mol% and ceria content 3.9 mol%. A sintered body of this comparative example was obtained from a certain yttria-ceria stabilized zirconia.

[0112] Comparative Example 3 The yttria concentration is 3.0 mol% and the ceria concentration is 3.9 mol%. Yttria and cerium chloride heptahydrate were added to and mixed with hydrated zirconia sol, respectively. Except for the addition of a different compound, the method was the same as in Example 1, and the mixture contained 5% by mass of alumina with the remainder being yttria. Yttria and ceria stabilized with a content of 3.0 mol% and a ceria content of 3.9 mol%. A zirconia powder for this comparative example, consisting of zirconia, was obtained.

[0113] Alumina was prepared in the same manner as in Example 1, except that the obtained zirconia powder was used. It contains mass% of yttria and ceria, with the remainder being 3.0 mol% yttria and 3.9 mol% ceria. A sintered body of this comparative example made of a certain yttria-stabilized zirconia was obtained.

[0114] Comparative Example 4 In the same manner as in Example 1 except that yttria was not added to the hydrated zirconia sol, alumina was contained at 5% by mass, and the balance was yttria-stabilized zirconi a zirconia powder of this comparative example composed of zirconia was obtained.

[0115] In the same manner as in Example 1 except that the obtained zirconia powder was used, alumina was 5 % by mass, and the balance was yttria-stabilized zirconia with a yttria content of 3.9 mol%, a sintered body of this comparative example composed of yttria-stabilized zirconia was obtained.

[0116] Comparative Example 5 Yttria was added to and mixed with the hydrated zirconia sol so that the yttria concentration became 3.0 mol%, and neither cerium chloride heptahydrate nor α-alumina powder was used. In the same manner as in Example 1, a zirconia powder of this comparative example composed of yttria-stabilized zirconia with a yttria content of 3.0 mol% was obtained.

[0117] In the same manner as in Example 1 except that the obtained zirconia powder was used and the sintering temperature was 1500 °C, a sintered body of this comparative example composed of yttria-stabilized zirconia with a yttria content of 3.0 mol% was obtained.

[0118] The results of the above examples and comparative examples are shown in the following table.

[0119]

Table 1

[0120] In the table above, although impact marks were observed in the condition after the ball drop test, the "formation of impact marks" was not considered. The column for cases where impact marks were not observed is marked with "○", and the column for cases where no impact marks were observed is marked with "×". Figure 7 shows the actual results. The appearance of the sintered body after the ball drop test in Example 1 is shown. As can be seen from Figure 7, the falling weight in the ball drop test made contact The affected area forms an impact mark (indentation) without cracking or other fractures, that is, Impact marks (indentations) as evidence of plastic deformation can be observed. Figure 8 shows the results obtained by optical microscope observation. This image shows a magnified view of the impact mark (magnification: 20x). The impact mark is a circular indentation approximately 2.8 mm in diameter. Furthermore, the depth of the impact mark (recess) relative to the thickness of the sintered body was 2.5. Examples 1 to 5, in which the turtoria content is 0.7 mol% or more and less than 1.5 mol%, are The sintered body has a tetragonal crystalline phase and contains 95% zirconia by mass, and is relatively dense. These sintered bodies had a density equivalent to over 98% in terms of degree. Visual inspection revealed this to be the case shown in Figure 7. Similar impact marks, which are traces of plastic deformation, were confirmed in Examples 1 to 5. However, no effect of ceria content on the formation of impact marks was observed. Regardless, it can be confirmed that all sintered bodies in this embodiment have a drop ball strength of 1 J or more. .

[0121] Figure 9 shows the appearance of the sintered body of Comparative Example 3 after the ball drop test, observed under an optical microscope (magnification: 20x). As shown, in Comparative Example 3, without forming an impact mark due to plastic deformation, Hertz fracture occurred. The cracks are progressing, and the sintered body is being destroyed as a result. On the other hand, yttria-containing Sintered bodies containing 1.5 mol% or more showed no impact marks and had a drop ball strength of 0.4 J. The following confirms that the impact resistance is significantly lower. Also, in Comparative Example 4, which does not contain yttria... Defects such as cracks occurred during sintering, and no measurable sintered body could be obtained. Comparative Example 5 shows that sintered bodies with only yttria as a stabilizer do not have a plastic deformation region. This was confirmed.

[0122] The sintered body of Example 1 had a surface I before the drop test. (004) / (220) and parts other than the impact point I (004) / (220) While the value was 0.55, the I of the impact point after the drop test (00 4) / (220) The value was 3.43. From this, the crystal orientation of the sintered body was determined by the ball drop test. It is evident that distinct gender-specific domains are emerging.

[0123] Furthermore, the sintered bodies of Examples 1 to 6 all exhibit similar color tones, for example, Example The sintered body of 1 is L * =92.41, a * = -3.89 and b * =16.01, and implementation The sintered body in Example 4 is L * =93.21, a * = -3.18 and b * The result was 18.38.

[0124] Example 6 Add cerium chloride heptahydrate to hydrated zirconia sol to achieve a ceria concentration of 3.9 mol%. Other than the fact that it was added and mixed, and that a slurry was made instead of using α-alumina powder. This was done in the same manner as in Example 1, with an yttria content of 1.1 mol% and a ceria content of 3.9 m The zirconia powder of this example consists of yttria-ceria stabilized zirconia in an ol% concentration. I got it.

[0125] The same method as in Example 1 was used, except that the obtained zirconia powder was used, and the remainder was It Yttria-Ceria is a compound containing 1.1 mol% yttria and 3.9 mol% ceria. A sintered body of this embodiment, made of stabilized zirconia, was obtained.

[0126] Example 7 Add cerium chloride heptahydrate to hydrated zirconia sol to achieve a ceria concentration of 3.9 mol%. It was added and mixed, and the alumina content was 1% by mass, α-al Except for adding alumina powder to form a slurry, the method was the same as in Example 1, but alumina was used as a single substance. The amount contains %, with the remainder being yttria content 1.1 mol% and ceria content 3.9 mol%. A zirconia powder of this example was obtained, consisting of yttria-ceria stabilized zirconia.

[0127] Except for using the obtained zirconia powder, the alumina was prepared in the same manner as in Example 1. It contains mass% of yttria and ceria, with the remainder being 1.1 mol% yttria and 3.9 mol% ceria. A sintered body of this embodiment was obtained, consisting of a certain yttria-ceria stabilized zirconia.

[0128] Example 8 Add cerium chloride heptahydrate to hydrated zirconia sol to achieve a ceria concentration of 3.9 mol%. It was added and mixed, and the alumina content was 3% by mass, α-al Except for adding alumina powder to form a slurry, the same method as in Example 1 was used to prepare alumina as three materials. The amount contains %, with the remainder being yttria content 1.1 mol% and ceria content 3.9 mol%. A zirconia powder of this example was obtained, consisting of yttria-ceria stabilized zirconia.

[0129] Alumina was prepared in the same manner as in Example 1, except that the obtained zirconia powder was used. It contains mass% of yttria and ceria, with the remainder being 1.1 mol% yttria and 3.9 mol% ceria. A sintered body of this embodiment was obtained, consisting of a certain yttria-ceria stabilized zirconia.

[0130] Example 9 Add cerium chloride heptahydrate to hydrated zirconia sol to achieve a ceria concentration of 3.9 mol%. It was added and mixed, and the alumina content was 7% by mass, α-al Except for adding alumina powder to form a slurry, the same method as in Example 1 was used to prepare alumina. The amount contains %, with the remainder being yttria content 1.1 mol% and ceria content 3.9 mol%. A zirconia powder of this example was obtained, consisting of yttria-ceria stabilized zirconia.

[0131] Alumina was prepared in the same manner as in Example 1, except that the obtained zirconia powder was used. It contains mass% of yttria and ceria, with the remainder being 1.1 mol% yttria and 3.9 mol% ceria. A sintered body of this embodiment was obtained, consisting of a certain yttria-ceria stabilized zirconia.

[0132] Example 10 Add α-alumina powder to the slurry so that the alumina content is 10% by mass. Except for the above, the method was the same as in Example 1, and the mixture contained 10% by mass of alumina, with the remainder being yttl Yttria-ceria stable yttria-ceria with a content of 1.1 mol% yttria and 3.4 mol% ceria. A zirconia powder consisting of zirconia was obtained in this embodiment.

[0133] Except for using the obtained zirconia powder, the alumina was prepared in the same manner as in Example 1. It contains 0% by mass, with the remainder being 1.1 mol% yttria and 3.4 mol% ceria. A sintered body of this embodiment was obtained, consisting of yttria-ceria stabilized zirconia.

[0134] Example 11 α-alumina powder is added to the slurry so that the alumina content is 16.4% by mass. Except for the use of Lee, the method was the same as in Example 1, and alumina was used, with the remainder being Yttria ceria contains 1.1 mol% yttria and 3.4 mol% ceria. A zirconia powder of this example, consisting of stabilized zirconia, was obtained.

[0135] Except for using the obtained zirconia powder, the alumina was prepared in the same manner as in Example 1. It contains 6.4% by mass, with the remainder being 1.1 mol% yttria and 3.4 mol% ceria. A sintered body of this embodiment was obtained, consisting of 1% yttria-ceria stabilized zirconia.

[0136] The results of the above examples are shown in the table below.

[0137] [Table 2]

[0138] From the table above, the sintered bodies of these examples have a density equivalent to 98% or more in terms of relative density. Furthermore, impact marks are formed regardless of the presence or absence of alumina content and its content. This can be confirmed. Furthermore, the zirconia content is in the range of 83.6% by mass or more and 100% by mass or less. Thus, it can be confirmed that it has a plastic deformation region. Note that the sintered body of Example 6 has a sintered body thickness of The depth of the impact point was 2.6. In addition, with increasing alumina content, Vickers It can be confirmed that there is a tendency for the hardness to increase.

[0139] The sintered bodies of Examples 6 to 11 all exhibit similar color tones, and the color tone is, for example, that of the sintered body of Example 6 is L * =83.98, a * = -4.69 and b *=20.00, the sintered body of Example 9 is L * =94.38, a * = -3.64 and b * =14.13, and the sintered body of Example 10 is L * =95.26, a * = -3.45 and b * The result was 14.22.

[0140] Example 12 The sintered body of this example was obtained using the same method as in Example 6, except that the sintering temperature was set to 1450°C. Ta.

[0141] Example 13 The sintered body of this example was obtained using the same method as in Example 7, except that the sintering temperature was set to 1450°C. Ta.

[0142] Example 14 The sintered body of this example was obtained using the same method as in Example 8, except that the sintering temperature was set to 1450°C. Ta.

[0143] Example 15 The sintered body of this example was obtained using the same method as in Example 2, except that the sintering temperature was set to 1450°C. Ta.

[0144] Example 16 The sintered body of this example was obtained using the same method as in Example 9, except that the sintering temperature was set to 1450°C. Ta.

[0145] The results of the above examples are shown in the table below.

[0146] [Table 3]

[0147] From Table 2 and the table above, even atmospheric pressure sintered bodies obtained at higher sintering temperatures have a relative density of It has a density equivalent to 98% or more, and has a plastic deformation region, as well as a low sintering temperature. It can be confirmed that the hardness tends to increase and the drop strength tends to decrease with this modification. .

[0148] Furthermore, the sintered bodies of Examples 12 to 16 all exhibit similar color tones, and the color tones are, for example, However, the sintered body of Example 12 is L * =83.52, a * = -4.75 and b * =24.35, The sintered body of Example 15 is L * =94.18, a * = -3.93 and b * = 16.79 Ta.

[0149] Example 17 The yttria concentration is 1.2 mol% and the ceria concentration is 3.6 mol%, Yttria and cerium chloride heptahydrate were added to and mixed with hydrated zirconia sol, respectively. The method is the same as in Example 1, except that the following was done and α-alumina powder was not used. Therefore, yttria has an yttria content of 1.2 mol% and a ceria content of 3.6 mol%. The zirconia powder of this embodiment, consisting of ceria-stabilized zirconia, was obtained.

[0150] The same method as in Example 1 was used, except that the obtained zirconia powder was used, and the remainder was It Yttria-Ceria is a compound containing 1.2 mol% yttria and 3.6 mol% ceria. A sintered body of this embodiment, made of stabilized zirconia, was obtained.

[0151] Example 18 The yttria concentration is 1.0 mol% and the ceria concentration is 4.0 mol%. Tortria and cerium chloride heptahydrate were added to and mixed with hydrated zirconia sol, respectively. The method was the same as in Example 1, except that α-alumina powder was not used. Yttria content 1.0 mol% and ceria content 4.0 mol%. A zirconia powder of this embodiment was obtained, consisting of ceria-stabilized zirconia.

[0152] The same method as in Example 1 was used, except that the obtained zirconia powder was used, and the remainder was It Yttria-Ceria is a compound containing 1.0 mol% yttria and 4.0 mol% ceria. A sintered body of this embodiment, made of stabilized zirconia, was obtained.

[0153] Comparative Example 6 The yttria concentration is 3.0 mol% and the ceria concentration is 3.9 mol%. A and cerium chloride heptahydrate were added to and mixed with hydrated zirconia sol, respectively. Furthermore, in the same manner as in Example 1, except that α-alumina powder was not used, Yttria ceria contains 3.0 mol% tria and 3.9 mol% ceria. A zirconia powder for this comparative example was obtained, consisting of stabilized zirconia.

[0154] The same method as in Example 1 was used, except that the obtained zirconia powder was used, and the remainder was It Yttria-Ceria is a compound containing 3.0 mol% yttria and 3.9 mol% ceria. A sintered body of this comparative example, consisting of regulated zirconia, was obtained.

[0155] The results for the examples and comparative examples are shown in the table below.

[0156] [Table 4]

[0157] Examples 17 and 18, and Example 12, show that alumina is not included, and yttria and It has also been confirmed that sintered bodies made of ceria-stabilized zirconia have a region of plastic deformation. Yes, it is possible. On the other hand, the sintered body of Comparative Example 6, despite having a lower ceria content than Example 18, Furthermore, it does not have a plastic deformation region, and the surface I before the drop test (004) / (220) and I other than the impact point (004) / (220) The value is 0.38, and the I of the impact point after the drop test. (004) / (220) The value is 0.80, and the I test was performed by a dropped ball test. (004) / (220) No significant changes were observed. [Explanation of symbols]

[0158] 100: External view showing an overview of the ball drop test. 101: Sintered body 102: Punching die 103a, 103b: Guide 104: Falling weight 105: Fixing tape 106: Sample stage of the ball-falling test machine 107: Protective tape 200: Sintered body of this embodiment after drop test 201: Sintered body 202: Impact mark (indentation) 203: Depth of impact marks (indentations) 300: Conventional sintered body after drop test 301: Sintered body 302: Defect (crack) 400: Diagram showing the state of the sintered body being placed on the sample stage of the drop test machine. 401: Sintered body 402: Fixing tape 403: Sample stand for the ball-falling test machine 404: Double-sided tape (protective tape) 500: Diagram showing the method for measuring impact mark depth. 501: Sintered body 502: Impact mark (indentation) 503A,B: Line Profile 504: Depth of the deepest part (L1 or L2) 601: Sintered body in a divided state 602: Defect (crack) 702: Impact mark (indentation)

Claims

1. A sintered body comprising one or more stabilizers selected from the group consisting of calcia, magnesia, and ceria, and zirconia containing yttria, wherein the yttria content is less than 1.5 mol%, and the ratio (molar ratio) of stabilizers other than yttria to yttria is 1.2 or more and 5.0 or less.

2. The sintered body according to claim 1, having a region in which an impact mark is formed when an impact force is applied.

3. The sintered body according to claim 2, wherein the impact mark is a recess.

4. A sintered body according to any one of claims 1 to 3, wherein the stabilizer content is 3 mol% or more and 10 mol% or less.

5. The sintered body according to any one of claims 1 to 4, wherein the stabilizing agent is yttria and ceria.

6. A sintered body according to any one of claims 1 to 5, wherein the ceria content is 2 mol% or more and 7.5 mol% or less.

7. A sintered body according to any one of claims 1 to 6, comprising alumina.

8. CIE1976 (L ＊ a ＊ b ＊ ) Brightness L in the color space ＊ A sintered body according to any one of claims 1 to 7, wherein the ratio is 80 or more.

9. A sintered body according to any one of claims 1 to 8, wherein the Vickers hardness is 12 GPa or less.

10. A member comprising a sintered body according to any one of claims 1 to 9.

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