Ni-based self-fluxing alloy

Abstract

To provide a Ni-based alloy excellent in self-fluxing property.SOLUTION: A Ni-based self-fluxing alloy for a coating film 6 contains P: 0.2 mass% or more and 6.0 mass% or less, B: 0.1 mass% or more and 4.5 mass% or less, Si: 0.1 mass% or more and 5.0 mass% or less, C: 0.00 mass% or more and 2.00 mass% or less, Cr: 0.0 mass% or more and 30.0 mass% or less, Mo: 0.0 mass% or more and 9.0 mass% or less, W: 0.0 mass% or more and 18.0 mass% or less, Cu: 0.0 mass% or more and 10.0 mass% or less, Mn: 0.0 mass% or more and 10.0 mass% or less, Fe: 0.0 mass% or more and 10.0 mass% or less, Co: 0.0 mass% or more and 10.0 mass% or less, Al: 0.00 mass% or more and 0.20 mass% or less, Ti: 0.00 mass% or more and 0.20 mass% or less, Zr: 0.00 mass% or more and 0.20 mass% or less, and Hf: 0.00 mass% or more and 0.20 mass% or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This specification discloses an alloy having self-fluxing properties. In particular, this specification discloses a self-fluxing alloy in which the base metal is Ni. [Background technology]

[0002] Various Ni-based self-fluxing alloys are specified in "JIS H8303 2010." Each Ni-based self-fluxing alloy contains B and Si. B and Si reduce oxides. B and Si can also lower the solidus or liquidus temperature of the alloy. This Ni-based self-fluxing alloy is subjected to a thermal spraying method, build-up welding method, centrifugal casting method, etc. to obtain a coating. This coating covers the main part of a metal product. This metal product has excellent corrosion resistance, wear resistance, etc.

[0003] The coating may be subjected to a remelting process. In the remelting process, the coating is heated, causing a liquid phase to appear in the coating. This liquid phase solidifies upon cooling. The remelting process can increase the density of the coating. Ni-based self-fluxing alloys are suitable for the remelting process because of their low solidus or liquidus temperatures. An example of a Ni-based self-fluxing alloy is disclosed in JP 2015-143372 A. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2015-143372 A Summary of the Invention [Problem to be solved by the invention]

[0005] The formation of the coating and the subsequent remelting process expose the main part to high temperatures. This thermal history causes damage to the main part. This thermal history also deteriorates the properties of the metal product. The self-fluxing properties of conventional alloys are insufficient.

[0006] The present inventors have intended to provide a Ni-based alloy with excellent self-fluxing properties. [Means for solving the problem]

[0007] Preferred Ni-based self-fluxing alloys are P: 0.2% by mass or more and 6.0% by mass or less, B: 0.1% by mass or more and 4.5% by mass or less, Si: 0.1% by mass or more and 5.0% by mass or less, C: 0.00% by mass or more and 2.00% by mass or less, Cr: 0.0 mass% or more and 30.0 mass% or less, Mo: 0.0 mass% or more and 9.0 mass% or less, W: 0.0 mass% or more and 18.0 mass% or less, Cu: 0.0 mass% or more and 10.0 mass% or less, Mn: 0.0 mass% or more and 10.0 mass% or less, Fe: 0.0 mass% or more and 10.0 mass% or less, Co: 0.0 mass% or more and 10.0 mass% or less, Al: 0.00 mass% or more and 0.20 mass% or less, Ti: 0.00 mass% or more and 0.20 mass% or less, Zr: 0.00 mass% or more and 0.20 mass% or less, and Hf: 0.00 mass% or more and 0.20 mass% or less The balance is Ni and unavoidable impurities. This alloy satisfies the following formulas (1), (2), and (3). 2.3 ≦ P% + B% + Si% ≦ 11.0 (1) Mo% + W% / 2 ≦ 9.0 (2) Al% + Ti% + Zr% + Hf% ≦ 0.20 (3) In these formulas, P% represents the mass content of P, B% represents the mass content of B, Si% represents the mass content of Si, Mo% represents the mass content of Mo, W% represents the mass content of W, Al% represents the mass content of Al, Ti% represents the mass content of Ti, Zr% represents the mass content of Zr, and Hf% represents the mass content of Hf. [Effects of the Invention]

[0008] This Ni-based self-fluxing alloy has a low solidus temperature or liquidus temperature. A dense coating can be formed from this Ni-based self-fluxing alloy by treatment at a relatively low temperature. This treatment does not expose the main part to high temperatures. Metal products having a coating obtained from this Ni-based self-fluxing alloy have excellent performance. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view schematically showing a part of a metal product according to one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Preferred embodiments will be described below with reference to the drawings as appropriate.

[0011] The metal product 2 shown in FIG. 1 has a main portion 4 and a coating 6. The coating 6 covers the surface of the main portion 4. The coating 6 may cover the entire surface of the main portion 4, or may cover only a portion of the surface. The main portion 4 is made of a metallic material. Various metallic materials are suitable for the main portion 4. Typical metallic materials are Fe-based alloys and Cu-based alloys. The coating 6 can be obtained by a thermal spraying method, an overlay welding method, a centrifugal casting method, or the like. These methods use powder.

[0012] This powder is an aggregate of many particles. The material of these particles is a Ni-based self-fluxing alloy. This Ni-based self-fluxing alloy is P: 0.2% by mass or more and 6.0% by mass or less, B: 0.1% by mass or more and 4.5% by mass or less, Si: 0.1% by mass or more and 5.0% by mass or less, C: 0.00% by mass or more and 2.00% by mass or less, Cr: 0.0 mass% or more and 30.0 mass% or less, Mo: 0.0 mass% or more and 9.0 mass% or less, W: 0.0 mass% or more and 18.0 mass% or less, Cu: 0.0 mass% or more and 10.0 mass% or less, Mn: 0.0 mass% or more and 10.0 mass% or less, Fe: 0.0 mass% or more and 10.0 mass% or less, Co: 0.0 mass% or more and 10.0 mass% or less, Al: 0.00 mass% or more and 0.20 mass% or less, Ti: 0.00 mass% or more and 0.20 mass% or less, Zr: 0.00 mass% or more and 0.20 mass% or less, and Hf: 0.00 mass% or more and 0.20 mass% or less The remainder is Ni and unavoidable impurities.

[0013] In conventional Ni-based self-fluxing alloys, B and Si contribute to self-fluxing. In the Ni-based self-fluxing alloy according to this embodiment, a portion of B or Si is substituted with P. This alloy has extremely excellent self-fluxing properties. The composition of this Ni-based self-fluxing alloy will be described in detail below.

[0014] [Phosphorus (P)] P lowers the solidus temperature. The addition of P makes it possible to achieve a low solidus temperature that could not be achieved with conventional Ni-based self-fluxing alloys. The addition of P makes it possible to achieve a dense coating 6 even when remelting is performed at temperatures below 1000°C, or even below 950°C. The solidus temperature in the binary equilibrium diagram of Ni and B is approximately 1093°C. The solidus temperature in the binary equilibrium diagram of Ni and Si is approximately 1143°C. On the other hand, the solidus temperature in the binary equilibrium diagram of Ni and P is approximately 870°C, which is significantly lower. It is presumed that these characteristics of P relative to Ni contribute to the low solidus temperature of the Ni-based self-fluxing alloy according to this embodiment. The coating 6 can be formed from a Ni-based self-fluxing alloy containing P at a low processing temperature. This processing can suppress thermal damage to the main portion 4.

[0015] In a conventional coating 6 made of a Ni-based self-fluxing alloy, B diffuses from the coating 6 to the main portion 4, potentially impairing the properties of the metal product 2. This is particularly likely to occur when the main portion 4 is made of an Fe-based alloy. For example, if the main portion 4 is made of SUS304 (austenitic stainless steel), the B that diffuses into the main portion 4 reacts with Cr to form chromium borides. This formation depletes Cr in the main portion 4, impairing the corrosion resistance of the main portion 4 near the interface with the coating 6. If the main portion 4 is made of SUS316 (Mo-containing austenitic stainless steel), the B that diffuses into the main portion 4 reacts with Cr and Mo to form chromium borides and molybdenum borides. This formation depletes Cr and Mo in the main portion 4, impairing the corrosion resistance of the main portion 4 near the interface with the coating 6. When the main portion 4 is made of mild steel, B diffused into the main portion 4 reacts with Fe to form iron borides. These iron borides have poor corrosion resistance. The inventors clarified the cause of the corrosion resistance degradation in conventional Ni-based self-fluxing alloys by observing the microstructure of the interface between the main portion 4 and the coating 6. After extensive research to suppress the corrosion resistance degradation, they arrived at a Ni-based self-fluxing alloy in which a portion of B or Si is substituted with P. In this alloy, P diffuses into the main portion 4. It is presumed that the diffusion of P suppresses the diffusion of B. In a main portion 4 in which the diffusion of B is suppressed, corrosion resistance degradation is less likely to occur.

[0016] The coating 6 can be formed by a thermal spraying method using powder. Because the Ni-based self-fluxing alloy contains P, this coating is dense. The reason for this is presumed to be as follows: In the thermal spraying method, high-temperature particles (molten metal) fly through space. As the particles fly, oxides, although small in amount, are formed on the particles. Because the Ni-based self-fluxing alloy contains P, some of the oxides formed on the particles contain P. Because the sublimation temperature of P-containing oxides is low, some of these P-containing oxides vaporize during flight. Therefore, the amount of oxides contained in the coating 6 is small. In this coating 6, the inhibition of denseness caused by oxides is suppressed.

[0017] From these viewpoints, the P content is preferably 0.2 mass% or more, more preferably 0.5 mass% or more, and particularly preferably 1.5 mass% or more. Excess P causes the precipitation of coarse phosphides in the coating 6. The coarse phosphides cause the coating 6 to become embrittled and inhibit the machinability of the coating 6. From the viewpoints of the toughness and workability of the coating 6, the P content is preferably 6.0 mass% or less, more preferably 5.5 mass% or less, and particularly preferably 4.0 mass% or less.

[0018] [Boron (B)] B is an essential element from the viewpoint of the self-fluxing property of the alloy. B lowers the solidus temperature of the Ni-based self-fluxing alloy. Furthermore, B can reduce oxides in the coating 6. From these viewpoints, the B content is preferably 0.1 mass% or more, more preferably 0.5 mass% or more, and particularly preferably 1.0 mass% or more. Excess B leads to the precipitation of coarse borides in the coating 6. The coarse borides increase the liquidus temperature of the coating 6, making the remelting treatment of the coating 6 difficult. From the viewpoint of ease of the remelting treatment, the B content is preferably 4.5 mass% or less, more preferably 4.0 mass% or less, and particularly preferably 3.5 mass% or less.

[0019] [Silicon (Si)] Si is an essential element from the viewpoint of the self-fluxing property of the alloy. Si lowers the solidus temperature of the Ni-based self-fluxing alloy. Furthermore, Si can reduce oxides in the coating 6. From these viewpoints, the Si content is preferably 0.1 mass% or more, more preferably 0.5 mass% or more, and particularly preferably 1.0 mass% or more. Excessive Si causes embrittlement of the coating 6 and inhibits the machinability of the coating 6. From the viewpoints of the toughness and workability of the coating 6, this content is preferably 5.0 mass% or less, more preferably 4.5 mass% or less, and particularly preferably 4.0 mass% or less.

[0020] [P, B and Si] This Ni-based self-fluxing alloy satisfies the following formula (1). 2.3 ≦ P% + B% + Si% ≦ 11.0 (1) In this formula, P% represents the mass content of P, B% represents the mass content of B, and Si% represents the mass content of Si. In this Ni-based self-fluxing alloy, the total content of P, B, and Si is 2.3 mass% or more and 11.0 mass% or less. A Ni-based self-fluxing alloy with a total content of 2.3 mass% or more has a low solidus temperature. From this perspective, this total content is more preferably 5.0 mass% or more, and particularly preferably 6.0 mass% or more. A Ni-based self-fluxing alloy with a total content of 11.0 mass% or less has a low liquidus temperature. From this perspective, this total content is more preferably 10.0 mass% or less, and particularly preferably 9.0 mass% or less.

[0021] [Carbon (C)] C contributes to the high hardness of the coating 6. C is added to the Ni-based self-fluxing alloy when high hardness is required for the coating 6. Therefore, C is not an essential element. From the viewpoint of high hardness, the C content is preferably 0.10 mass% or more, more preferably 0.20 mass% or more, and particularly preferably 0.40 mass% or more. Excess C causes embrittlement of the coating 6 and inhibits the machinability of the coating 6. From the viewpoint of the toughness and workability of the coating 6, this content is preferably 2.00 mass% or less, more preferably 1.50 mass% or less, and particularly preferably 1.00 mass% or less.

[0022] Chromium Cr contributes to the corrosion resistance of the coating 6. Cr is added to the Ni-based self-fluxing alloy when corrosion resistance is required for the coating 6. Therefore, Cr is not an essential element. From the viewpoint of corrosion resistance, the Cr content is preferably 4.0 mass% or more, more preferably 14.0 mass% or more, and particularly preferably 16.0 mass% or more. Excess Cr increases the liquidus temperature of the coating 6, making the remelting treatment of this coating 6 difficult. From the viewpoint of ease of remelting treatment, this content is preferably 30.0 mass% or less, more preferably 20.0 mass% or less, and particularly preferably 18.0 mass% or less.

[0023] [Molybdenum (Mo)] Mo contributes to the corrosion resistance of the coating 6. Mo is added to the Ni-based self-fluxing alloy when corrosion resistance is required for the coating 6. Therefore, Mo is not an essential element. From the viewpoint of corrosion resistance, the Mo content is preferably 0.5 mass% or more, more preferably 0.8 mass% or more, and particularly preferably 1.0 mass% or more. Excess Mo increases the liquidus temperature of the coating 6, making the remelting treatment of the coating 6 difficult. Excess Mo also causes the precipitation of coarse molybdenum-containing phosphides. The coarse phosphides embrittle the coating 6 and inhibit the machinability of the coating 6. From the viewpoints of ease of remelting treatment, toughness, and workability, the Mo content is preferably 9.0 mass% or less, more preferably 5.0 mass% or less, and particularly preferably 4.0 mass% or less.

[0024] [Tungsten (W)] W contributes to the corrosion resistance of the coating 6. W is added to the Ni-based self-fluxing alloy when corrosion resistance is required for the coating 6. Therefore, W is not an essential element. From the viewpoint of corrosion resistance, the W content is preferably 1.0 mass% or more, more preferably 1.5 mass% or more, and particularly preferably 2.0 mass% or more. Excess W increases the liquidus temperature of the coating 6, making the remelting treatment of the coating 6 difficult. Excess W also causes the precipitation of coarse tungsten-containing phosphides. The coarse phosphides cause the coating 6 to become embrittled and inhibit the machinability of the coating 6. From the viewpoints of ease of remelting treatment, toughness, and workability, the W content is preferably 18.0 mass% or less, more preferably 10.0 mass% or less, and particularly preferably 8.0 mass% or less.

[0025] [Mo and W] This Ni-based self-fluxing alloy satisfies the following formula (2). Mo% + W% / 2 ≦ 9.0 (2) In this formula, Mo% represents the mass content of Mo, and W% represents the mass content of W. In Ni-based self-fluxing alloys, W plays a role equivalent to that of Mo. However, the effect obtained by adding W is approximately half that obtained by adding the same amount of Mo. Therefore, in this embodiment, 1 / 2 is used as the coefficient for the W content to calculate the molybdenum equivalent (Mo% + W% / 2). In Ni-based self-fluxing alloys that satisfy the above formula, the molybdenum equivalent is 9.0 mass% or less. This Ni-based self-fluxing alloy can be easily remelted and can produce a coating 6 with excellent toughness and workability. From these perspectives, the molybdenum equivalent is more preferably 5.0 mass% or less, and particularly preferably 4.0 mass% or less. As mentioned above, Mo and W are not essential elements. Therefore, the molybdenum equivalent may be zero. From the viewpoint of corrosion resistance, the molybdenum equivalent is preferably 0.5 mass% or more, more preferably 0.8 mass% or more, and particularly preferably 1.0 mass% or more.

[0026] Copper (Cu) Cu contributes to the corrosion resistance of the coating 6. Cu is added to the Ni-based self-fluxing alloy when corrosion resistance is required for the coating 6. Therefore, Cu is not an essential element. From the viewpoint of corrosion resistance, the Cu content is preferably 0.1 mass% or more, more preferably 0.5 mass% or more, and particularly preferably 1.0 mass% or more. Excess Cu actually impairs the corrosion resistance of the coating 6. From the viewpoint of corrosion resistance, this content is preferably 10.0 mass% or less, more preferably 5.0 mass% or less, and particularly preferably 4.0 mass% or less.

[0027] [Manganese (Mn)] Mn does not significantly affect the properties of the Ni-based self-fluxing alloy according to this embodiment. Mn is not an essential component of the Ni-based self-fluxing alloy. Therefore, the Mn content in this Ni-based self-fluxing alloy may be zero. Excess Mn reduces the content of essential elements. Therefore, the Mn content is preferably 10.0 mass% or less.

[0028] [Iron (Fe)] Fe does not significantly affect the properties of the Ni-based self-fluxing alloy according to this embodiment. Fe is not an essential component of the Ni-based self-fluxing alloy. Therefore, the content of Fe in this Ni-based self-fluxing alloy may be zero. Excess Fe reduces the content of essential elements. Therefore, the content of Fe is preferably 10.0 mass% or less.

[0029] [Cobalt (Co)] Co does not significantly affect the properties of the Ni-based self-fluxing alloy according to this embodiment. Co is not an essential component of the Ni-based self-fluxing alloy. Therefore, the Co content in this Ni-based self-fluxing alloy may be zero. Excess Co reduces the content of essential elements. Therefore, the Co content is preferably 10.0 mass% or less.

[0030] [Aluminum (Al)] In this embodiment, Al is an impurity. Excessive Al forms a strong oxide film and inhibits the denseness of the film 6. From the viewpoint of denseness, the Al content is preferably 0.20 mass% or less, more preferably 0.15 mass% or less, and particularly preferably 0.10 mass% or less. The ideal Al content is zero.

[0031] [Titanium (Ti)] In this embodiment, Ti is an impurity. Excess Ti forms a strong oxide film and inhibits the denseness of the film 6. From the viewpoint of denseness, the Ti content is preferably 0.20 mass% or less, more preferably 0.15 mass% or less, and particularly preferably 0.10 mass% or less. The ideal Ti content is zero.

[0032] [Zirconium (Zr)] In this embodiment, Zr is an impurity. Excess Zr forms a strong oxide film and inhibits the denseness of the film 6. From the viewpoint of denseness, the Zr content is preferably 0.20 mass% or less, more preferably 0.15 mass% or less, and particularly preferably 0.10 mass% or less. The ideal Zr content is zero.

[0033] [Hafnium (Hf)] In this embodiment, Hf is an impurity. Excess Hf forms a strong oxide film and inhibits the denseness of the film 6. From the viewpoint of denseness, the Hf content is preferably 0.20 mass% or less, more preferably 0.15 mass% or less, and particularly preferably 0.10 mass% or less. The ideal Hf content is zero.

[0034] [Al, Ti, Zr and Hf] This Ni-based self-fluxing alloy satisfies the following formula (3). Al% + Ti% + Zr% + Hf% ≦ 0.20 (3) In this formula, Al% represents the mass content of Al, Ti% represents the mass content of Ti, Zr% represents the mass content of Zr, and Hf% represents the mass content of Hf. In a Ni-based self-fluxing alloy that satisfies this formula, the total content of Al, Ti, Zr, and Hf is 0.20 mass% or less. In this Ni-based self-fluxing alloy, the formation of a strong oxide film is suppressed. Therefore, in this Ni-based self-fluxing alloy, a dense film 6 can be formed. From this perspective, this total content is preferably 0.20 mass% or less, more preferably 0.15 mass% or less, and particularly preferably 0.10 mass% or less. The ideal total content is zero.

[0035] [Powder production] The powder is preferably obtained by atomization. Gas atomization, disk atomization, water atomization, centrifugal atomization, etc. are employed. Gas atomization and disk atomization are preferred. The powder obtained by atomization may be subjected to mechanical milling, etc.

[0036] [Film formation] Typically, the coating 6 is formed by a thermal spraying method. In the thermal spraying method, particles made of a Ni-based self-fluxing alloy are heated and melted, and then sprayed onto the main portion 4. The molten metal that collides with the main portion 4 solidifies and forms a solidified layer. Since the particles are sprayed continuously, the molten particles also collide with and solidify the solidified layer, causing the solidified layer to grow. In this manner, the coating 6 is formed. Since the Ni-based self-fluxing alloy according to this embodiment contains P, the particles can be melted by heating at a relatively low temperature. The temperature of this molten metal can be low. Therefore, damage to the main portion 4 caused by heat can be suppressed. Even if the main portion 4 is made of a low-melting-point material (e.g., a Cu alloy), melting and deformation of the main portion 4 can be suppressed. As described above, some of the P-containing oxides vaporize during the flight of the molten metal. Therefore, the amount of oxide contained in the coating 6 is small. The coating 6 is dense. The coating 6 may be formed by a method other than the thermal spraying method. Methods other than the thermal spraying method include build-up welding and centrifugal casting. Since the solidus temperature of the Ni-based self-fluxing alloy is low, damage to the main portion 4 can be suppressed in either method.

[0037] [Remelting process] The coating 6 may be subjected to a remelting process. In the remelting process, the coating 6 is heated to a temperature equal to or higher than the solidus temperature. This heating generates a liquid phase in the coating 6. The coating 6 is in a solid-liquid mixed state. This liquid phase solidifies, and the coating 6 is reformed. The remelting process increases the density of the coating 6. Because the Ni-based self-fluxing alloy according to this embodiment contains P, a liquid phase can be generated at a relatively low heating temperature. Therefore, damage to the main portion 4 caused by heat can be suppressed. [Example]

[0038] The effects of the Ni-based self-fluxing alloy according to the examples will be clarified below, but the scope of the present specification should not be construed as being limited based on the description of these examples.

[0039] [Example 1] Metals with the compositions shown in Table 1 were melted to obtain a molten metal. This molten metal was placed in an alumina crucible. The molten metal was discharged from the nozzle of the crucible and sprayed with high-pressure nitrogen gas to obtain a powder. This powder was classified using a sieve to adjust the particle size to 45 μm or more and 125 μm or less. A plate-shaped main part made of SUS304 and measuring 100 × 100 × 10 mm was prepared. The powder was subjected to a gas flame spraying method to form a coating with a thickness of 1 mm on the surface of the main part. This main part and coating were placed in an electric furnace and held at 940°C for 30 minutes. The coating was air-cooled to obtain the metal product of Example 1.

[0040] [Examples 2-4, 6-7, and 9-25 and Comparative Examples 26-29, 31-32, and 34-48] Metal products of Examples 2-4, 6-7, and 9-25 and Comparative Examples 26-29, 31-32, and 33-48 were obtained in the same manner as in Example 1, except that the compositions were as shown in the following Tables 1 and 2. The alloys of Comparative Examples 26-33 correspond to SFNi1-8 specified in JIS.

[0041] [Example 5 and Comparative Example 30] Metal products of Example 5 and Comparative Example 30 were obtained in the same manner as in Example 1, except that the compositions were as shown in Tables 1 and 2 below and the main parts were made of SUS316.

[0042] [Example 8 and Comparative Example 33] Metal products of Example 8 and Comparative Example 33 were obtained in the same manner as in Example 1, except that the compositions were as shown in Tables 1 and 2 below and the main parts were made of SS400.

[0043] [Solidus and liquidus temperatures] The solidus temperature and liquidus temperature of the powder were measured using a thermal analyzer (DTA) under the following conditions. Powder amount: 30g Atmosphere: After evacuation, argon gas was flowed at 200 ml / min. Heating rate: 20°C / min Starting temperature: room temperature Achieved temperature: 1500℃ (held for 5 minutes) Cooling rate: -20℃ / min Among the exothermic peaks observed in the DTA signal during cooling, the highest temperature at which heat generation begins is the liquidus temperature, and the lowest temperature at which heat generation ends is the solidus temperature. The results are shown in Tables 3 and 4 below.

[0044] [Residual pores and residual oxides] A test specimen was cut from the coating before the remelting treatment, and the cross section was polished. The test specimen was photographed near the center of the coating thickness direction using an optical microscope at 100x magnification. The obtained image was observed, and the number of residual pores and residual oxides with a size (major axis) of 20µm or more within an area of 500 x 500µm was counted. The results were graded according to the following criteria. A: 5 or less B: 6 or more but less than 30 C: 30 or more Test pieces were similarly taken from the remelted coating and rated in the same manner, with the results shown in Tables 3 and 4 below.

[0045] [Corrosion resistance] Test pieces were cut out from the coating after the remelting treatment, and the cross sections were polished. These test pieces were subjected to a corrosion resistance test. The test pieces of Examples 1-7 and 9-25 and Comparative Examples 26-32 and 34-48 were subjected to a salt spray test. The test pieces of Example 8 and Comparative Example 33 were subjected to a high-temperature, high-humidity test. The test conditions for each test were as follows: Salt spray test Salt water composition: 5% NaCl aqueous solution Temperature: 35℃ Time: 96h High temperature and humidity test Temperature: 70℃ Humidity: 95%RH Time: 96 hours After the test, the coating and the interface between the coating and the main part were observed and rated according to the following criteria. A: Rust is visible in some areas B: Rust is visible throughout The results are shown in Tables 3 and 4 below.

[0046] [Hardness] A test piece was cut out from the coating after the remelting treatment, and the cross section was polished. The Vickers hardness of this cross section was measured at a load of 2.94 N. The average values of the five measurement results are shown in Tables 3 and 4 below.

[0047] [Table 1]

[0048] In Examples 1-24, Al, Ti, Zr, and Hf are unavoidable impurities. In Example 25, Al, Ti, Zr, and Hf are intentionally added or left as residual elements. Table 1 shows the measured values of the contents of these impurities.

[0049] [Table 2] In Comparative Examples 26-47, Al, Ti, Zr, and Hf are unavoidable impurities. In Comparative Example 48, Al, Ti, Zr, and Hf are intentionally added or left as residual elements. Table 2 shows the measured values of the contents of these impurities.

[0050] [Table 3]

[0051] [Table 4]

[0052] As shown in Tables 3 and 4, the metal products according to each example are excellent in various performances. These evaluation results clearly demonstrate the superiority of this Ni-based self-fluxing alloy.

[0053] [Disclosure items] Each of the following sections is a disclosure of a preferred embodiment.

[0054] [Item 1] P: 0.2% by mass or more and 6.0% by mass or less, B: 0.1% by mass or more and 4.5% by mass or less, Si: 0.1% by mass or more and 5.0% by mass or less, C: 0.00% by mass or more and 2.00% by mass or less, Cr: 0.0 mass% or more and 30.0 mass% or less, Mo: 0.0 mass% or more and 9.0 mass% or less, W: 0.0 mass% or more and 18.0 mass% or less, Cu: 0.0 mass% or more and 10.0 mass% or less, Mn: 0.0 mass% or more and 10.0 mass% or less, Fe: 0.0 mass% or more and 10.0 mass% or less, Co: 0.0 mass% or more and 10.0 mass% or less, Al: 0.00 mass% or more and 0.20 mass% or less, Ti: 0.00 mass% or more and 0.20 mass% or less, Zr: 0.00 mass% or more and 0.20 mass% or less, and Hf: 0.00 mass% or more and 0.20 mass% or less and the balance being Ni and unavoidable impurities, and satisfying the following formulas (1), (2), and (3). 2.3 ≦ P% + B% + Si% ≦ 11.0 (1) Mo% + W% / 2 ≦ 9.0 (2) Al% + Ti% + Zr% + Hf% ≦ 0.20 (3) (In these formulas, P% represents the mass content of P, B% represents the mass content of B, Si% represents the mass content of Si, Mo% represents the mass content of Mo, W% represents the mass content of W, Al% represents the mass content of Al, Ti% represents the mass content of Ti, Zr% represents the mass content of Zr, and Hf% represents the mass content of Hf.)

[0055] [Item 2] The material is a Ni-based self-fluxing alloy, The Ni-based self-fluxing alloy is P: 0.2% by mass or more and 6.0% by mass or less, B: 0.1% by mass or more and 4.5% by mass or less, Si: 0.1% by mass or more and 5.0% by mass or less, C: 0.00% by mass or more and 2.00% by mass or less, Cr: 0.0 mass% or more and 30.0 mass% or less, Mo: 0.0 mass% or more and 9.0 mass% or less, W: 0.0 mass% or more and 18.0 mass% or less, Cu: 0.0 mass% or more and 10.0 mass% or less, Mn: 0.0 mass% or more and 10.0 mass% or less, Fe: 0.0 mass% or more and 10.0 mass% or less, Co: 0.0 mass% or more and 10.0 mass% or less, Al: 0.00 mass% or more and 0.20 mass% or less, Ti: 0.00 mass% or more and 0.20 mass% or less, Zr: 0.00 mass% or more and 0.20 mass% or less, and Hf: 0.00 mass% or more and 0.20 mass% or less and the remainder being Ni and unavoidable impurities, and satisfying the following formulas (1), (2), and (3): 2.3 ≦ P% + B% + Si% ≦ 11.0 (1) Mo% + W% / 2 ≦ 9.0 (2) Al% + Ti% + Zr% + Hf% ≦ 0.20 (3) (In these formulas, P% represents the mass content of P, B% represents the mass content of B, Si% represents the mass content of Si, Mo% represents the mass content of Mo, W% represents the mass content of W, Al% represents the mass content of Al, Ti% represents the mass content of Ti, Zr% represents the mass content of Zr, and Hf% represents the mass content of Hf.)

[0056] [Item 3] The material is a Ni-based self-fluxing alloy, The Ni-based self-fluxing alloy is P: 0.2% by mass or more and 6.0% by mass or less, B: 0.1% by mass or more and 4.5% by mass or less, Si: 0.1% by mass or more and 5.0% by mass or less, C: 0.00% by mass or more and 2.00% by mass or less, Cr: 0.0 mass% or more and 30.0 mass% or less, Mo: 0.0 mass% or more and 9.0 mass% or less, W: 0.0 mass% or more and 18.0 mass% or less, Cu: 0.0 mass% or more and 10.0 mass% or less, Mn: 0.0 mass% or more and 10.0 mass% or less, Fe: 0.0 mass% or more and 10.0 mass% or less, Co: 0.0 mass% or more and 10.0 mass% or less, Al: 0.00 mass% or more and 0.20 mass% or less, Ti: 0.00 mass% or more and 0.20 mass% or less, Zr: 0.00 mass% or more and 0.20 mass% or less, and Hf: 0.00 mass% or more and 0.20 mass% or less and the remainder being Ni and unavoidable impurities, and satisfying the following formulas (1), (2), and (3): 2.3 ≦ P% + B% + Si% ≦ 11.0 (1) Mo% + W% / 2 ≦ 9.0 (2) Al% + Ti% + Zr% + Hf% ≦ 0.20 (3) (In these formulas, P% represents the mass content of P, B% represents the mass content of B, Si% represents the mass content of Si, Mo% represents the mass content of Mo, W% represents the mass content of W, Al% represents the mass content of Al, Ti% represents the mass content of Ti, Zr% represents the mass content of Zr, and Hf% represents the mass content of Hf.)

[0057] [Item 4] The device has a main portion and a coating covering the surface of the main portion, The material of the coating is a Ni-based self-fluxing alloy, The Ni-based self-fluxing alloy is P: 0.2% by mass or more and 6.0% by mass or less, B: 0.1% by mass or more and 4.5% by mass or less, Si: 0.1% by mass or more and 5.0% by mass or less, C: 0.00% by mass or more and 2.00% by mass or less, Cr: 0.0 mass% or more and 30.0 mass% or less, Mo: 0.0 mass% or more and 9.0 mass% or less, W: 0.0 mass% or more and 18.0 mass% or less, Cu: 0.0 mass% or more and 10.0 mass% or less, Mn: 0.0 mass% or more and 10.0 mass% or less, Fe: 0.0 mass% or more and 10.0 mass% or less, Co: 0.0 mass% or more and 10.0 mass% or less, Al: 0.00 mass% or more and 0.20 mass% or less, Ti: 0.00 mass% or more and 0.20 mass% or less, Zr: 0.00 mass% or more and 0.20 mass% or less, and Hf: 0.00 mass% or more and 0.20 mass% or less and the remainder is Ni and unavoidable impurities, and satisfies the following formulas (1), (2), and (3). 2.3 ≦ P% + B% + Si% ≦ 11.0 (1) Mo% + W% / 2 ≦ 9.0 (2) Al% + Ti% + Zr% + Hf% ≦ 0.20 (3) (In these formulas, P% represents the mass content of P, B% represents the mass content of B, Si% represents the mass content of Si, Mo% represents the mass content of Mo, W% represents the mass content of W, Al% represents the mass content of Al, Ti% represents the mass content of Ti, Zr% represents the mass content of Zr, and Hf% represents the mass content of Hf.) [Industrial Applicability]

[0058] The alloys described above are suitable for a variety of applications where self-fluxing properties are required.

Claims

1. P: 0.2% by mass or more and 6.0% by mass or less, B: 0.1% by mass or more and 4.5% by mass or less, Si: 0.1% by mass or more and 5.0% by mass or less, C: 0.00% by mass or more and 2.00% by mass or less, Cr: 0.0% by mass or more and 30.0% by mass or less, Mo: 0.5% by mass or more and 9.0% by mass or less, W: 0.0% by mass or more and 18.0% by mass or less, Cu: 0.1% by mass or more and 10.0% by mass or less, Mn: 0.0% by mass or more and 10.0% by mass or less, Fe: 0.0% by mass or more and 10.0% by mass or less, Co: 0.0% by mass or more and 10.0% by mass or less, Al: 0.00% by mass or more and 0.20% by mass or less, Ti: 0.00% by mass or more and 0.20% by mass or less, Zr: 0.00% by mass or more and 0.20% by mass or less, and Hf: 0.00 mass% or more and 0.20 mass% or less and the balance being Ni and unavoidable impurities, and satisfying the following formulas (1), (2), and (3): 2.3 ≦ P% + B% + Si% ≦ 11.0 (1) 0.5≦Mo%+W% / 2≦9.0 (2) Al% + Ti% + Zr% + Hf% ≦ 0.20 (3) (In these formulas, P% represents the mass content of P, B% represents the mass content of B, Si% represents the mass content of Si, Mo% represents the mass content of Mo, W% represents the mass content of W, Al% represents the mass content of Al, Ti% represents the mass content of Ti, Zr% represents the mass content of Zr, and Hf% represents the mass content of Hf.)

2. The material is a Ni-based self-fluxing alloy, The Ni-based self-fluxing alloy is P: 0.2% by mass or more and 6.0% by mass or less, B: 0.1% by mass or more and 4.5% by mass or less, Si: 0.1% by mass or more and 5.0% by mass or less, C: 0.00% by mass or more and 2.00% by mass or less, Cr: 0.0% by mass or more and 30.0% by mass or less, Mo: 0.5% by mass or more and 9.0% by mass or less, W: 0.0% by mass or more and 18.0% by mass or less, Cu: 0.1% by mass or more and 10.0% by mass or less, Mn: 0.0% by mass or more and 10.0% by mass or less, Fe: 0.0% by mass or more and 10.0% by mass or less, Co: 0.0% by mass or more and 10.0% by mass or less, Al: 0.00% by mass or more and 0.20% by mass or less, Ti: 0.00% by mass or more and 0.20% by mass or less, Zr: 0.00% by mass or more and 0.20% by mass or less, and Hf: 0.00 mass% or more and 0.20 mass% or less and the balance being Ni and unavoidable impurities, and satisfying the following formulas (1), (2), and (3). 2.3 ≦ P% + B% + Si% ≦ 11.0 (1) 0.5≦Mo%+W% / 2≦9.0 (2) Al% + Ti% + Zr% + Hf% ≦ 0.20 (3) (In these formulas, P% represents the mass content of P, B% represents the mass content of B, Si% represents the mass content of Si, Mo% represents the mass content of Mo, W% represents the mass content of W, Al% represents the mass content of Al, Ti% represents the mass content of Ti, Zr% represents the mass content of Zr, and Hf% represents the mass content of Hf.)

3. The material is a Ni-based self-fluxing alloy, The Ni-based self-fluxing alloy is P: 0.2% by mass or more and 6.0% by mass or less, B: 0.1% by mass or more and 4.5% by mass or less, Si: 0.1% by mass or more and 5.0% by mass or less, C: 0.00% by mass or more and 2.00% by mass or less, Cr: 0.0% by mass or more and 30.0% by mass or less, Mo: 0.5% by mass or more and 9.0% by mass or less, W: 0.0% by mass or more and 18.0% by mass or less, Cu: 0.1% by mass or more and 10.0% by mass or less, Mn: 0.0% by mass or more and 10.0% by mass or less, Fe: 0.0% by mass or more and 10.0% by mass or less, Co: 0.0% by mass or more and 10.0% by mass or less, Al: 0.00% by mass or more and 0.20% by mass or less, Ti: 0.00% by mass or more and 0.20% by mass or less, Zr: 0.00% by mass or more and 0.20% by mass or less, and Hf: 0.00 mass% or more and 0.20 mass% or less and the balance being Ni and unavoidable impurities, and satisfying the following mathematical formulas (1), (2), and (3). 2.3 ≦ P% + B% + Si% ≦ 11.0 (1) 0.5≦Mo%+W% / 2≦9.0 (2) Al% + Ti% + Zr% + Hf% ≦ 0.20 (3) (In these formulas, P% represents the mass content of P, B% represents the mass content of B, Si% represents the mass content of Si, Mo% represents the mass content of Mo, W% represents the mass content of W, Al% represents the mass content of Al, Ti% represents the mass content of Ti, Zr% represents the mass content of Zr, and Hf% represents the mass content of Hf.)

4. The device has a main portion and a coating covering the surface of the main portion, the coating is made of a Ni-based self-fluxing alloy, The Ni-based self-fluxing alloy is P: 0.2% by mass or more and 6.0% by mass or less, B: 0.1% by mass or more and 4.5% by mass or less, Si: 0.1% by mass or more and 5.0% by mass or less, C: 0.00% by mass or more and 2.00% by mass or less, Cr: 0.0% by mass or more and 30.0% by mass or less, Mo: 0.5% by mass or more and 9.0% by mass or less, W: 0.0% by mass or more and 18.0% by mass or less, Cu: 0.1% by mass or more and 10.0% by mass or less, Mn: 0.0% by mass or more and 10.0% by mass or less, Fe: 0.0% by mass or more and 10.0% by mass or less, Co: 0.0% by mass or more and 10.0% by mass or less, Al: 0.00% by mass or more and 0.20% by mass or less, Ti: 0.00% by mass or more and 0.20% by mass or less, Zr: 0.00% by mass or more and 0.20% by mass or less, and Hf: 0.00 mass% or more and 0.20 mass% or less and the balance being Ni and unavoidable impurities, and satisfying the following mathematical formulas (1), (2), and (3). 2.3 ≦ P% + B% + Si% ≦ 11.0 (1) 0.5≦Mo%+W% / 2≦9.0 (2) Al% + Ti% + Zr% + Hf% ≦ 0.20 (3) (In these formulas, P% represents the mass content of P, B% represents the mass content of B, Si% represents the mass content of Si, Mo% represents the mass content of Mo, W% represents the mass content of W, Al% represents the mass content of Al, Ti% represents the mass content of Ti, Zr% represents the mass content of Zr, and Hf% represents the mass content of Hf.)

Images