Metal member and product
The metal member, comprising Ru x Re y M z with a hexagonal close-packed structure, addresses the instability and limitations of traditional resistance heating elements by offering improved high-temperature and mechanical properties at a lower cost.
Patent Information
- Application Number
- JP2023208247
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-12-11
- Publication Date
- 2025-06-23
AI Technical Summary
Existing metal resistance heating elements, such as those made from tantalum, tungsten, and molybdenum, undergo changes in electrical resistivity and mechanical strength due to recrystallization during energization heating, leading to instability and potential disconnection. Additionally, these materials have limitations in terms of temperature dependence of electrical resistivity and mechanical properties.
A metal member composed of Ru x Re y M z, where M is two or more metals other than Ru and Re, and x + y + z = 1, with M being 0.1 at% or more, and having a primary crystal part with a hexagonal close-packed structure. This alloy is designed to provide excellent high-temperature characteristics and mechanical properties while being cost-effective.
The proposed metal member achieves improved high-temperature characteristics and mechanical properties, including enhanced durability and controllability of electrical resistivity, while being more cost-effective than traditional materials like tantalum.
Smart Images
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Abstract
Description
Technical Field
[0001] The present invention relates to metal members and products.
Background Art
[0002] In a resistance heating furnace, a direct current or an alternating current is applied to a resistance heating element disposed in the furnace to cause the resistance heating element to generate heat and heat the inside of the furnace. Generally, carbon-based materials such as carbon and SiC, ceramic materials such as zirconia and lanthanum chloride, and metal-based materials such as tungsten and tantalum are used for the resistance heating element. The material that can be used for the resistance heating element is mainly selected according to the atmosphere required for heating and the target temperature to be reached.
[0003] For example, an evaporation cell used for film formation in the production of an organic electroluminescence device is a kind of resistance heating furnace, and generally the inside of the furnace is set to a high vacuum (~10 5 Pa or so) and used. In vacuum evaporation using this type of evaporation cell, a crucible-shaped container filled with an evaporation raw material is placed in a region surrounded by a resistance heating element, and the inside of the furnace is heated by energizing the resistance heating element to melt the evaporation raw material in the container. Atoms or molecules desorbed from the surface of the melted evaporation raw material are given directivity by the evaporation cell and adhere to a substrate disposed above the evaporation cell, thereby proceeding with film formation.
[0004]
[0005] In the film formation as described above, since it is required that the desorption of substances other than the evaporation raw material inside the evaporation cell is small, the resistance heating element that can be used for the evaporation cell is limited to substances with low volatility in a high temperature and high vacuum.Conventionally, as resistance heating elements, refractory metals such as tungsten, molybdenum, and tantalum, which are exclusively of high melting point and low vapor pressure, have been used. In particular, tantalum, unlike tungsten and molybdenum, has high ductility, making it easy to process into a desired resistance heating element shape even at room temperature, so it is widely used. Also, tantalum has a higher electrical resistivity compared to tungsten and molybdenum, so heating can be achieved with a lower current to heat a resistance heating element of the same volume, which has the advantage of enabling miniaturization and reduction in diameter of the current source and wires. Note that tantalum, tungsten, and molybdenum used for resistance heating elements are all used in the state of pure metal or an alloy containing a small amount of additives.
Prior Art Documents
Non-Patent Documents
[0006]
Non-Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0007] However, existing metal resistance heating elements are polycrystalline because they are formed through machining such as forging and wire drawing, and recrystallization occurs during energization heating, resulting in changes over time in electrical resistivity and mechanical strength. As a result, there have been problems such as changes in the applied current and voltage conditions for raising the temperature to a predetermined temperature, and a decrease in mechanical strength causing deformation of the resistance heating element, leading to unexpected contact with peripheral members or disconnection. Also, in the process of use, there has often been a problem that the formation of a nodular structure deteriorates the electrical and mechanical properties and leads to disconnection.
[0008] Also, as described above, tantalum has a higher electrical resistivity compared to tungsten and molybdenum, but has a low electrical resistivity with respect to the required characteristics. Furthermore, there is a problem that the temperature dependence of the electrical resistivity of tantalum is larger than that of tungsten or molybdenum. Generally, the electrical resistivity of a metal increases with an increase in temperature. However, tantalum, compared to tungsten and molybdenum, a slight temperature change leads to a change in the electrical resistivity, and the controllability of temperature by controlling voltage or current is low.
[0009] Recently, in response to these problems, as alternative materials for tantalum, improvement of the electrical characteristics of metal members using noble metals such as ruthenium (Ru) has been studied (Non-Patent Document 1). However, these metal members also have problems such as high cost, and are not always satisfactory in terms of mechanical properties, etc. For this reason, there is a long-awaited need for an inexpensive metal member having excellent heat resistance, corrosion resistance, and mechanical properties.
[0010] The present invention has been made to solve the above-described problems, and an object thereof is to provide an inexpensive metal member having excellent high-temperature characteristics and mechanical properties.
Means for Solving the Problems
[0011] The metal member according to the present invention contains Ru x Re y M z (wherein M is two or more metals other than Ru and Re, and x + y + z = 1), and M is 0.1 at% or more with respect to the entire metal member, and further has a primary crystal part having a hexagonal close-packed structure.
[0012] In one configuration example of the above metal member, M is two or more D-block metals.
[0013] In one configuration example of the above metal member, M is two or more Group 6 metals.
[0014] In one configuration example of the above metal member, M is Mo and W.
[0015] In one configuration example of the above metal member, the composition ratio of Ru and Re is 1 or more in terms of atomic ratio.
[0016] In one configuration example of the above metal member, the total content of Ru, Re, and M is 60 at% or more with respect to the entire metal member.
[0017] In one configuration example of the above metal member, the content of M is in the range of 0.1 at% to 50 at% with respect to the entire metal member.
[0018] In one configuration example of the above metal member, the metal member is a wire.
[0019] The product according to the present invention is a product including the above metal member.
[0020] In one configuration example of the above product, the product is a component of a heating device, a film forming device, or a crystal growth device.
[0021] In one configuration example of the above product, the product is a reaction device, a reaction vessel, or a component thereof.
[0022] In one configuration example of the above product, the product includes a wire made of the above metal member.
[0023] In one configuration example of the above product, the product is a heater.
[0024] In one configuration example of the above product, the product is a heating device, a film forming device, or a crystal growth device.
Advantages of the Invention
[0025] As described above, according to the present invention, Ru x Re y M z(wherein M is two or more metals other than Ru and Re, and x + y + z = 1), and M is 0.1 at% or more with respect to the entire metal member. Further, since it has a primary crystal part with a hexagonal close-packed structure, a metal member that is inexpensive and has excellent high-temperature characteristics and mechanical characteristics can be provided.
Brief Description of the Drawings
[0026]
Figure 1A
Figure 1B
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
Embodiments for Carrying Out the Invention
[0027] Hereinafter, a metal member according to an embodiment of the present invention will be described. This metal member contains Ru x Re y M zA metal member containing at least (where M is two or more metals other than Ru and Re, and x + y + z = 1), with M being 0.1 at% or more with respect to the entire metal member. Further, this metal member has a primary crystal part with a hexagonal close-packed structure. This metal member is a so-called alloy.
[0028] For example, in the metal member according to the embodiment, M can be two or more d-block metals, and M can also be two or more Group 6 metals. Also, in the metal member according to the embodiment, M can be Mo and W. Further, in the metal member according to the embodiment, the composition ratio of Ru and Re can be 1 or more in terms of atomic ratio. By setting this composition ratio, it is preferable because the resistance to the load of the metal member can be further improved.
[0029] Also, in the metal member according to the embodiment, by setting the total content of Ru, Re, and M to 60 at% or more with respect to the entire metal member, it can be made inexpensive and have more balanced and excellent high-temperature characteristics and mechanical characteristics.
[0030] Also, in the metal member according to the embodiment, the content of M can be in the range of 0.1 at% to 50 at% with respect to the entire metal member. By setting the content of M within this range, it is preferable because the adhesion and stability as an alloy of the metal member can be further improved.
[0031] Also, the metal member according to the embodiment can further contain at least one additive element selected from the group consisting of Ir, Rh, Pt, Pd, and Os. The content of this additive element can be 0.001 at% to 15 at% with respect to the entire metal member. By including the additive element with the content within this range, the heat resistance and corrosion resistance of the metal member can be further improved.
[0032] Note that the "metal member" does not mean only a metal member composed only of an element (metal material) containing Ru, Re, and at least one of the elements Mo and W, but means a member containing at least each of the above-described elements and can contain other elements. Further, the shape of this metal member is not particularly limited, and for example, it also includes a metal member to which components or members made of materials such as ceramics, other metals, and plastics are joined. Note that the metal member according to the present invention can contain inevitable impurities.
[0033] Since the metal member according to the embodiment is inexpensive and excellent in heat resistance, corrosion resistance, and mechanical properties, it can be used as a wire. In the present invention, the metal member can be easily manufactured by the μ-PD method.
[0034] In a preferred μ-PD method, as shown in FIGS. 1A and 1B, a molten metal 103 as a raw material is accommodated in a crucible 102 that can be heated by a high-frequency induction coil 101, and a metal (wire) 105 solidified through a growth crystal 104 is pulled down while passing through a nozzle 106 to grow crystals. The nozzle 106 is provided at the bottom 107 of the crucible 102. The crucible 102 is supported and fixed on a crucible stand 109 inside a processing chamber 108. Note that FIG. 1B shows an enlarged view of the inside of the dotted circle in FIG. 1A.
[0035] The metal member manufactured in this way not only has excellent crystallinity but also has better mechanical properties such as elongation and strength. Even when used as a wire, higher durability can be achieved, and furthermore, more excellent mechanical properties, high-temperature properties, etc. can be exhibited.
[0036] The metal member according to the embodiment can be applied to various products according to a conventional method. For example, it can be suitably used as a heating device, a film forming device, a crystal growth device, or parts thereof. Further, the metal member according to the embodiment can also be suitably used as a reaction device, a reaction vessel, or parts thereof. The heating device, the film forming device, the crystal growth device, the reaction device, or the reaction vessel can be known devices such as a heater device, a CVD device, a PLD device, a vapor phase crystal growth device, and a liquid phase crystal growth device. Further, the parts can be known parts of the device (for example, parts for an evaporation cell, a heater wire, a brazing material, etc.).
[0037] Hereinafter, it will be described in more detail using examples.
[0038] [Example 1] Using Ru, Mo, W, and Re raw materials with a purity of 99.9% or more, Ru 0.6-x Mo 0.15 W 0.25 Re x (x = 0.01, 0.1, 0.15) alloy button ingots were produced by an arc melting method, and φ0.8 mm wires were grown by the Dewetting μ-PD method to obtain samples of the metal member of the present invention. The produced samples were cut, and heat treatment was carried out in a high-purity Ar atmosphere at a temperature condition of 2273 K for a treatment time of 3 hours. When composition analysis and crystal orientation analysis were performed on the heat-treated samples by wavelength dispersive fluorescence X-ray spectroscopy (WDX) and electron backscatter diffraction (EBSD) methods, all the wires had good crystallinity of Ru 0.6-x Mo 0.15 W 0.25 Re x (x = 0.01, 0.1, 0.15) alloy wires were confirmed.
[0039] In FIG. 2, the grown Ru 0.59 Mo 0.15 W 0.25 Re 0.01A photograph of the wire rod is shown. (a) in Fig. 2 shows the whole of the wire rod grown to a length of 14.2 m wound in a ring and bundled, and (b) in Fig. 2 shows a partially enlarged view. The wire diameter of this wire rod was 0.80 ± 0.01 mm, and the surface was smooth. Also, Ru 0.59 Mo 0.15 W 0.25 Re 0.01 The wire rod was a very high-quality single-crystal alloy wire rod as shown in the photograph of Fig. 3. Incidentally, the grown Ru 0.59 Mo 0.15 W 0.25 Re 0.01 The wire rod showed a maximum tensile strength of about 658 MPa and a good elongation at break of about 89%.
[0040] Ru produced as a sample of the metal member of the present invention 0.6-x Mo 0.15 W 0.25 Re x (x = 0.01, 0.1, 0.15) For any of the alloy wire rods (Re-substituted alloy wire rods), a wire rod of 1 m or more was obtained, and it was easily bendable at room temperature. Also, by thermodynamic calculation, the solidus temperature increased according to the Re substitution amount, and the solidus temperature of Ru 0.45 Mo 0.15 W 0.25 Re 0.15 was estimated to be about 2493 K. Also, in the above configuration, the primary crystal part had a hexagonal close-packed (HCP) structure, and it was also possible to confirm microporosity with a true circle equivalent diameter of 20 μm or less formed in a row-like manner derived from the primary crystal part of the HCP structure. Therefore, the metal member according to the present invention can include microporosity with a true circle equivalent diameter of 20 μm or less formed in a row-like manner in the longitudinal direction, derived from the primary crystal part of the HCP structure.
[0041] [Example 2] By the same method as in Example 1 described above, Ru, Mo, W, and Re raw materials with a purity of 99.9% or more were used to obtain Ru 0.6-x Mo 0.15 W 0.25 Re x(x = 0, 0.01, 0.1, 0.15) alloy button ingots were fabricated, and wire rods with a diameter of φ0.8 mm were grown to obtain sample wire rods. The evaluation results of each fabricated sample wire rod are shown in FIGS. 4 to 7. FIG. 4 shows the results of the micro-indentation test, and FIG. 5 shows the results of the indentation elastic modulus test. From the micro-indentation test in FIG. 4 and the results of the indentation elastic modulus test in FIG. 5, Ru 0.6-x Mo 0.15 W 0.25 Re x the mechanical properties were particularly good when the Re content in the alloy was between 1 atomic % and 15 atomic %.
[0042] FIG. 6 shows the evaluation results of the electrical resistivity. From the evaluation results of the electrical resistivity such as FIG. 6, Ru 0.6-x Mo 0.15 W 0.25 Re x it was found that the properties of the alloy were excellent when the Re content was more than 0 atomic % and less than 23 atomic %, and the properties were even more excellent when it was between 0.3 atomic % and 15 atomic %. FIG. 7 shows the test evaluation results of elongation. From the test evaluation results of elongation such as FIG. 7, Ru 0.6-x Mo 0.15 W 0.25 Re x it was found that the elongation was more excellent when the Re content in the alloy was between 4 atomic % and 14 atomic %.
[0043] As described above, according to the present invention, Ru x Re y M z (wherein M is two or more metals other than Ru and Re, and x + y + z = 1) is included at least, M is 0.1 at % or more with respect to the whole of the metal member, and further, since it has a primary crystal part with a hexagonal close-packed structure, a metal member that is inexpensive and excellent in high-temperature properties and mechanical properties can be provided.
[0044] It should be noted that the present invention is not limited to the embodiments described above, and it is obvious that many modifications and combinations can be implemented by those having ordinary knowledge in the art within the technical idea of the present invention.
Description of Symbols
[0045] 101…High-frequency induction coil, 102…Crucible, 103…Molten metal, 104…Grown crystal, 105…Solidified metal (wire rod), 106…Nozzle, 107…Bottom, 108…Processing chamber, 109…Crucible stand.
Claims
1. Ru x Re y M z (wherein M is two or more metals other than Ru and Re, and x + y + z = 1), a metal member comprising at least, M is 0.1 at% or more with respect to the whole of the metal member, Further, A metal member having a primary crystal part with a hexagonal close-packed structure.
2. In the metal member according to Claim 1, M is a metal member which is two or more d-block metals.
3. In the metal member according to Claim 1, M is a metal member which is two or more Group 6 metals.
4. In the metal member according to Claim 1, M is a metal member which is Mo and W.
5. In the metal member according to Claim 1, A metal member in which the composition ratio of Ru and Re is 1 or more in terms of atomic ratio.
6. In the metal member according to Claim 1, The total content of Ru, Re, and M is 60 at% or more with respect to the whole of the metal member. A metal member.
7. In the metal member according to Claim 1, The content of M is in the range of 0.1 at% to 50 at% with respect to the whole of the metal member. A metal member.
8. The metal member according to Claim 1 which is a wire.
9. A product including a metal member, wherein the metal member is the metal member according to Claim 1.
10. The product according to Claim 9 which is a component of a heating device, a film forming device, or a crystal growth device.
11. The product according to claim 9, which is a reaction device, a reaction vessel or a part thereof.
12. A product comprising a wire made of a metal member, wherein the metal member is the metal member according to claim 1.
13. The product according to claim 10, which is a heater.
14. The product according to claim 9 or 12, which is a heating device, a film forming device or a crystal growth device.