JP7018603B2 - Manufacturing method of clad layer - Google Patents

Description

The present invention relates to a method for manufacturing a metal member and a clad layer. More specifically, the present invention is a method for manufacturing a metal member and a clad layer having a clad layer capable of providing a metal member having excellent wear resistance in a wide operating temperature range from room temperature to high temperature even on the surface of a large part. Regarding.

Materials with excellent high-temperature characteristics are required in a wide range of fields such as the automobile field, energy, steelmaking, and aerospace fields.
Although the performance of cemented carbide (WC-Co) as a wear-resistant material is excellent, it cannot be used in a high temperature range of 700 ° C. or higher because Co, which is a bonded phase, softens as the temperature rises and WC oxidizes.
Therefore, the inventors have so far performed a Ni ₃ Al-based intermetallic compound having a two-overlapping phase structure, which has a small decrease in hardness even at high temperatures and has a hardness higher than that of cemented carbide in a temperature range of 800 ° C. or higher. A cast material of an alloy was proposed (see Patent No. 5146935: Patent Document 1).

However, when the heat-resistant member is formed of a cast material of a Ni (nickel) -based alloy, the main component of the entire member must be Ni, so that the manufacturing cost is higher than when the member is formed of an iron-based alloy. There's a problem. Therefore, by forming a coating film of a nickel-based alloy having high hardness and high-temperature wear resistance on a base material made of an iron-based alloy whose hardness decreases at high temperatures, the manufacturing cost is reduced and the heat-resistant member is made. It is possible to manufacture.
As a method for forming a coating film of a nickel-based alloy, a method of spraying and coating a Ni ₃ Al-based intermetallic compound alloy is known (for example, see Japanese Patent Application Laid-Open No. 2015-63752: Patent Document 2). Further, a friction stir welding tool in which the probe body is coated with a nickel-based alloy having a two-overlapping phase structure is known (Japanese Patent Laid-Open No. 2014-105379: Patent Document 3 and Japanese Patent Application Laid-Open No. 2014-105381: Patent). See Document 4).

However, when a sprayed film of a nickel-based alloy is formed on a base material by thermal spraying, voids penetrating from the film surface to the base material may exist, which may cause corrosion or oxidation of the base material, and the heat resistance characteristics and life of the heat-resistant member. The characteristics are low. In addition, although the sprayed coating is physically bonded to the base material by the anchor effect, the adhesion strength between the base material and the sprayed coating is not sufficiently high, and when used under harsh conditions, the sprayed coating is removed from the base material. There is also the problem that it is easy to peel off. Further, although it is suitable for forming a thin film (usually about 300 μm) by thermal spraying, as described above, the thermal spraying film does not have high adhesion strength, so that when a thick film is formed, peeling easily occurs, and a thick film is formed. There is a problem that it is difficult.
When a nickel-based alloy coating film is formed on a base material by shielded metal arc welding, there is a problem that the high-temperature hardness characteristics of the coating film are deteriorated because the base material components are mixed in the coating film.
Further, in the techniques described in Patent Documents 3 and 4 above, a nickel-based intermetallic compound alloy containing Ta is used as the material of the coating layer formed on the base material, and such a coating layer is formed. It is desirable to keep the manufacturing (material) cost as low as possible.

The room temperature hardness of the nickel-based intermetallic compound alloy is 400 to 600 HV, which is inferior to that of cemented carbide (1400 HV) as well as tool steel (about 800 HV).
Therefore, based on such a background, the inventors have developed a nickel-based intermetallic compound alloy as a bonding phase of ceramic particles such as carbides as a material capable of exhibiting excellent wear resistance in a wide temperature range from room temperature to high temperature. We have proposed a composite material produced by a powder metallurgy method using the above (see Patent No. 6011946: Patent Document 5).

Japanese Patent No. 5146935 JP-A-2015-63752 Japanese Unexamined Patent Publication No. 2014-105379 Japanese Unexamined Patent Publication No. 2014-105381 Japanese Patent No. 6011946

The powder metallurgy method is a method of manufacturing a product by filling a mold with raw material powder, molding it, and baking it at a high temperature, but the size that can be manufactured is limited by the mold, so there is a limit. On the other hand, many of the products that require wear resistance at high temperatures are large, and it is impossible to manufacture them by the powder metallurgy method.
In order to improve the wear resistance of large products, a method of covering with a hard material by overlay welding is used, but the conventional material cannot be said to have sufficient wear resistance at high temperature. In addition, there is a method of compounding metal and carbide particles by a plasma powder overlay method, but the carbide particles are biased in the overlay layer and the carbide particles are dissolved in a high-temperature metal liquid. There is a problem.
Further, when the carbide is dissolved in the bonded phase, the composition of the bonded phase deviates from the original one. Therefore, when a material such as an intermetallic compound that can exert its function only in a specific composition is used as a bonded phase, the function is lost due to the composition change due to the dissolution of the carbide.
For these reasons, it has been considered difficult to fabricate a ceramic particle dispersion composite using a nickel-based intermetallic compound alloy as a bonded phase by the overlay welding method.

The present invention has been made in view of such circumstances, and includes a base material and a ceramics / intermetallic compound composite clad layer using a nickel-based intermetallic compound alloy as a bonding phase of ceramic particles such as carbides. In addition, a metal member that can be manufactured at low cost and has excellent hardness characteristics at high temperatures, and a clad layer that forms such a clad layer on a substrate by a laser metal deposition (LMD) method or the like. The challenge is to provide a method.
The above-mentioned "binding phase" is also referred to as a "binder phase" and is also referred to as a "matrix" in the present invention.

The present inventors have described the above-mentioned metal member provided with a base material and a clad layer composed of a matrix which is a nickel-based intermetallic compound having a specific composition and dispersed ceramic particles thereof. We have found that the problem can be solved and have completed the present invention.

Further, according to the present invention, Ni of 65 at% or more and 80 at% or less, Al of 4 at% or more and 15 at% or less, V of 4 at% or more and 15 at% or less , Nb of more than 0 at% and 8 at% or less, and Ni. , B (boron) of 10% by weight or more and 1000% by weight or less with respect to the total weight of Al, V and Nb , and an intermetallic compound alloy powder having a total alloy composition of 100% consisting of unavoidable impurities, and V, Nb. A carbide of one or more elements selected from the group consisting of and W, and ceramic particles having a particle size of 1 μm or more and 150 μm or less are injected onto the base material together with a carrier gas to emit heat source light to the base material. Including the step of forming a clad layer by irradiation,
The mixing ratio of the ceramic particles to the clad layer is 10 to 60% by volume.
Provided is a method for producing a clad layer, characterized in that at least a part of the intermetallic compound alloy powder is melted by receiving the heat source light and deposited on the substrate together with the ceramic particles.

According to the present invention, a base material and a ceramics / intermetallic compound composite clad layer using a nickel-based intermetallic compound alloy as a bonding phase of ceramic particles such as carbides can be produced at low cost. It is possible to provide a metal member having excellent hardness characteristics at a high temperature and a method for producing a clad layer in which such a clad layer is formed on a substrate by a laser metal deposition method or the like.
That is, according to the present invention, it is possible to provide a member having excellent wear resistance in a wide operating temperature range from room temperature to high temperature even on the surface of a large part which has been difficult to apply. Metal parts are expected to be used in a wide range of industrial fields such as automobiles, aircraft, energy / power generation, chemical plants, and steel makers as product parts that require wear resistance, strength, corrosion resistance, and oxidation resistance at high temperatures.
Further, in the present invention, the clad layer exhibits high high-temperature hardness and high-temperature wear resistance, and an iron-based material can be used as the base material, so that a relatively inexpensive metal member can be provided. Further, by providing the clad layer, the metal member can be repaired or regenerated.

The metal member of the present invention further exerts the above-mentioned effect when at least one of the following requirements is satisfied.
(1) Carbides, nitrides, carbonitrides of one or more elements selected from the group in which the ceramic particles are Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Al and Y. Particles containing oxides, carbides or boronides.
(2) The ceramic particles are particles containing carbides, nitrides, carbonitrides, oxides, silicides or borides of the elements constituting the matrix.
(3) The ceramic particles are carbides of one or more elements selected from the group consisting of V, Nb and W.
(4) The ceramic particles have a particle size of 1 μm or more and 150 μm or less.
(5) The matrix has a two overlapping phase structure composed of an initial analysis L1 ₂ phase and an eutectoid structure of the L1 ₂ phase and the D0 ₂₂ phase.
(6) The matrix is heat-treated at a temperature of 800 ° C. or higher to form a two-overlapping phase structure composed of an initial analysis L1 _{2 phase and an eutectic structure of the L1 2 phase} and the D0 ₂₂ phase, or an L1 ₂ phase and D0 ₂₂ . It has an alloy composition that forms an eutectoid structure of the phase.
(7) The base material is an iron-based alloy or nickel, cobalt and titanium selected from the group consisting of stainless steel, alloy tool steel, rolled steel for general structure, carbon steel for machine structure and alloy steel for machine structure, and theirs. It is a non-iron alloy selected from the group consisting of alloys.

Further, the method for producing a clad layer of the present invention further exerts the above-mentioned effect when at least one of the following requirements is satisfied.
(8) In the step of forming the clad layer, the base material is irradiated with heat source light a plurality of times while injecting the intermetallic compound alloy powder and the ceramic particles together with the carrier gas onto the base material to form a multilayer clad layer. It is a process.
(9) Further includes a step of heat-treating the clad layer at a temperature of 800 ° C. or higher and 1320 ° C. or lower.

It is explanatory drawing of the manufacturing method of the clad layer of one Embodiment of this invention. It is an appearance photograph of the clad layer of the metal member of this invention. It is an SEM photograph of the cross section (deposition area) of the matrix of the clad layer of the metal member before and after the heat treatment of this invention. It is an EPMA map of each element about the matrix part of the clad layer after the heat treatment of the metal member WC of this invention. It is an EPMA map of each element about the matrix part of the clad layer after the heat treatment of the metal member VC of this invention. It is an EPMA map of each element about the matrix part of the clad layer after the heat treatment of the metal member NbC of this invention. It is an X-ray-diffraction diagram of the clad layer before and after the heat treatment of the metal member WC, the metal member VC and the metal member NbC of the present invention. It is a figure which shows the Vickers hardness distribution in the vicinity of the surface of the clad layer before and after the heat treatment of a metal member WC, a metal member VC and a metal member NbC.

(1) Metal member The metal member of the present invention comprises a base material and a clad layer covering the base material.
The clad layer is composed of a matrix made of an intermetallic compound alloy and ceramic particles dispersed in the matrix.
The matrix is 65 at% or more and 80 at% or less of Ni, 4 at% or more and 15 at% or less of Al, 4 at% or more and 15 at% or less of V, and 0 at% or more and 8 at% or less of Nb, Ta, Mo, Co. B (boron) of 10% by weight or more and 1000% by weight or less with respect to the total weight of one or more fourth elements selected from the group consisting of Cr, Si, W and Ti, and Ni, Al, V and the fourth element. ), Inevitable impurities, 0 at% or more and 10 at% or less of the mixed impurities from the base material, and 0 at% or more and 5 at% or less of the mixed impurities from the ceramic particles, and having a total alloy composition of 100%. It is characterized by being a metal-to-metal compound alloy (also referred to as a "nickel-based metal-to-metal compound alloy").
Here, the "nickel group" means that the amount of nickel is the largest among the elements contained in the intermetallic compound alloy, and the content thereof is at least 50 at% or more, and in the present invention. Is preferably 65 at% or more.

[Clad layer]
The clad layer is composed of a matrix made of an intermetallic compound alloy and ceramic particles dispersed in the matrix.
The thickness of the clad layer is not particularly limited and may be appropriately set according to the purpose and application thereof.
For example, it can be 0.8 mm or more and 5 mm or less, 1 mm or more and 4 mm or less, and 5 mm or more.
The clad layer may have a multi-layer structure formed by stacking a plurality of times. The forming method will be described in the manufacturing method.

[matrix]
The matrix consists of Ni of 65 at% or more and 80 at% or less, Al of 4 at% or more and 15 at% or less, V of 4 at% or more and 15 at% or less, and Nb, Ta, Mo, Co, Cr of 0 at% or more and 8 at% or less. B (boron) of 10% by weight or more and 1000% by weight or less with respect to the total weight of one or more fourth elements selected from the group consisting of Si, W and Ti, and Ni, Al, V and the fourth element. A metal having a total alloy composition of 0 at% or more and 10 at% or less, mixed impurities from the base material, and 0 at% or more and 5 at% or less, mixed impurities from the ceramic particles. It is an intermetallic alloy.

The Ni content in the alloy composition is 65 at% or more and 80 at% or less.
If the Ni content is less than 65 at%, an intermetallic compound phase having a 3: 1 composition such as Ni ₃ Al or Ni ₃ V may not be formed. On the other hand, if the Ni content exceeds 80 at%, a Ni solid solution phase may be formed.
More specifically, the Ni content (at%) is 65, 65.5, 66, 66.5, 67, 67.5, 68, 68.5, 69, 69.5, 70, 70.5. , 71, 71.5, 72, 72.5, 73, 73.5, 74, 74.5, 75, 75.5, 76, 76.5, 77, 77.5, 78, 78.5, 79 , 79.5, 80 may be in the range between any two numerical values, preferably 67 at% or more and 77 at% or less.

The Al (aluminum) content in the alloy composition is 4 at% or more and 15 at% or less.
If the Al content is less than 4 at%, the Ni ₃ Al phase may not be formed. On the other hand, when the Al content exceeds 15 at%, a brittle intermetallic compound phase such as Ni ₅ Al ₃ may appear.
More specifically, the Al content (at%) is 4,4.5,5,5.5,6,6.5,7,7.5,8,8.5,9,9.5. It may be in the range of any two numerical values of 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15 and is preferable. It is 5 at% or more and 10 at% or less.

The V (vanadium) content in the alloy composition is 4 at% or more and 15 at% or less.
If the V content is less than 4 at%, the Ni ₃ V phase may not be formed. On the other hand, if the V content exceeds 15 at%, the oxidation resistance may decrease.
More specifically, the V content (at%) is 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5. It may be in the range of any two numerical values of 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15 and is preferable. It is 7 at% or more and 14 at% or less.

The content of the fourth element in the alloy composition is 0 at% or more and 8 at% or less. That is, the fourth element is an optional component and does not have to be contained, and may contain an amount of 8 at% or less. When the content of the fourth element exceeds 8 at%, Ni ₃ Al, Ni ₃ V Intermetallic compound phases other than the above may be formed.
More specifically, the content (at%) of the fourth element is 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, It may be in the range between any two numerical values of 5.5, 6, 6.5, 7, 7.5, and 8, and is preferably 0 at% or more and 6 at% or less.

The B (boron) content in the alloy composition is 10% by weight or more and 1000% by weight or less with respect to the total weight of Ni, Al, V and the fourth element.
If the B content is less than 10 wt ppm, the effect of suppressing grain boundary cracking may not be obtained. On the other hand, if the B content exceeds 1000 wt ppm, a low melting point phase may be formed.
More specifically, the B content (weight ppm) is any of 10, 20, 30, 40, 50, 70, 100, 200, 300, 400, 500, 600, 700, 800, 900, and 1000 weight ppm. It may be in the range between the two numerical values, and is preferably 20% by weight or more and 500% by weight or less.

The fourth element is one or more selected from the group consisting of Nb, Ta, Mo, Co, Cr, Si, W and Ti. Among these, Nb is preferable in terms of strength improving effect, and hardness is improved. W is preferable in terms of effect.
The effect of improving the strength of Nb (niobium) increases with the increase of niobium up to 5 at%, and the effect saturates when the content exceeds 5 at%, resulting in coarsening of intermetallic compound phases such as Ni ₃ Nb phase. Since multiple appearances are considered, the content of niobium is preferably 5 at% or less (including cases where it is not contained).
Further, the hardness improving effect of W (tungsten) is limited when the content is less than 0.5 at%, and it is considered that the effect may be saturated when the content exceeds 8 at%. Therefore, the content of tungsten is considered to be saturated. The amount is preferably 0.5 at% or more and 8 at% or less.

Ta (tantalum) is considered to be an effective element for solid solution strengthening (hardening). The effect is limited when the tantalum content is less than 0.5 at%, and it is considered that the effect may be saturated when the tantalum content exceeds 8 at%. Therefore, the tantalum content is 0.5 at% or more and 8 at. % Or less is preferable.

Mo (molybdenum) is considered to be an effective element for solid solution strengthening (hardening) and precipitation strengthening (hardening). The effect is limited when the molybdenum content is less than 0.5 at%, and it is considered that the effect may be saturated when the molybdenum content exceeds 5 at%. Therefore, the molybdenum content is 1 at% or more and 5 at% or less. Is preferable.

Co (cobalt) is considered to have an effect of improving oxidation resistance. The effect becomes remarkable as the cobalt content increases up to 6 at%, and it is considered that the cobalt content may be saturated when it exceeds 6 at%. Therefore, the cobalt content is preferably 0.5 at% or more and 6 at% or less. ..
Cr (chromium) is considered to have the effects of improving oxidation resistance and reducing the weight (reducing the density). The effect becomes remarkable as the chromium content increases up to 7 at%, and it is considered that the effect may be saturated when the chromium content exceeds 7 at%. Therefore, the chromium content is 0.5 at% or more. 7 at% or less is preferable.

Si (silicon) is considered to be an element effective for solid solution strengthening (hardening), weight reduction (low density), and improvement of oxidation resistance. The effect is limited when the silicon content is less than 0.1 at%, and it is considered that the effect may be saturated when the silicon content exceeds 3 at%. Therefore, the silicon content is 0.1 at% or more and 3 at% or less. Is preferable.
Ti (titanium) is considered to have an effect of improving strength. The effect becomes remarkable as the titanium content increases up to 5 at%, and it is considered that the effect may be saturated when the titanium content exceeds 5 at%. Therefore, the titanium content is 0 at% or more and 5 at% or less. Is preferable.

The unavoidable impurities are impurities inevitably contained in the intermetallic compound alloy, and include impurities inevitably contained in the material used for producing the intermetallic compound alloy.
The impurities mixed from the base material are impurities mixed from the base material into the intermetallic compound alloy during the production of the clad layer, and the content thereof is 0 at% or more and 10 at% or less.
If the content of impurities mixed from the base material exceeds 10 at%, it may adversely affect the physical properties of the intermetallic compound alloy, and it is preferably 0 at% (not contained), but avoid mixing in the manufacturing process. Is difficult, and its content is preferably 6 at% or less.
The impurities mixed from the ceramic particles are impurities mixed from the ceramic particles into the intermetallic compound alloy during the production of the clad layer, and the content thereof is 0 at% or more and 5 at% or less.
If the content of impurities mixed from the ceramic particles exceeds 5 at%, it may adversely affect the physical properties of the intermetallic compound alloy, and it is preferably 0 at% (not contained), but avoid mixing in the manufacturing process. Is difficult, and its content is preferably 4 at% or less.

The matrix is a two-overlapping phase structure consisting of an eutectoid L1 ₂ phase and an eutectoid structure of the L1 ₂ phase and a D0 ₂₂ phase, that is, a two-overlapping phase structure containing Ni ₃ Al and Ni ₃ V, or L1. It may have a _two -phase and _D022 phase eutectoid structure.
The clad layer of the intermetallic compound alloy formed by the LMD method described later is usually a precursor of the so-called two-overlapping phase structure, which does not have the fine structure of the above-mentioned two-overlapping phase structure. By subjecting such a precursor to a heat treatment described later, a clad layer of an intermetallic compound alloy having a fine structure having a two-overlapping phase structure can be formed.
That is, the matrix is formed by heat treatment at a temperature of 800 ° C. or higher to form a two-overlapping phase structure composed of an initial analysis L1 ₂ phase and an eutectic structure of the L1 ₂ phase and the D0 ₂₂ phase, or an L1 ₂ phase and D0 ₂₂ . It may have an alloy composition that forms an eutectoid structure of the phase.

[Ceramic particles]
The ceramic particles (also referred to as "hard particles") are dispersed in the matrix constituting the clad layer, and contribute to the improvement of the strength (hardness) of the clad layer of the metal member.
It was difficult to uniformly disperse the ceramic particles in the metal / alloy by the conventional melt casting method or the like, but in the present invention, since the LMD method as described later is used, the intermetallic matrix is used. Ceramic particles can be uniformly dispersed in the compound alloy.
The ceramic particles include carbides, nitrides, carbonitrides, and oxides of one or more elements selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Al, and Y. , Carbide or boron containing boron. Among these, carbides, nitrides and carbonitrides are preferable from the viewpoint of being able to supply carbon or nitrogen as an entertaining element into the alloy composition of the matrix.

Further, by selecting the carbides of the elements contained in the metal-to-metal compound alloy of the matrix as the ceramic particles, the alloy characteristics of the metal-to-metal compound phase are not deteriorated even if the components of the ceramic particles are mixed in the matrix. Therefore, it is preferable that the ceramic particles are particles containing carbides, nitrides, carbonitrides, oxides, siliceous compounds or borohydrides of the elements constituting the matrix, and are selected from the group consisting of V, Nb and W. It is preferably a carbide of one or more elements to be formed.

The ceramic particles preferably have a particle size of 1 μm or more and 150 μm or less.
The particle size of the ceramic particles contained in the clad layer may be smaller than that of the raw material particles described later due to dissolution, recrystallization, etc. associated with the thermal history of the manufacturing process.
If the particle size of the ceramic particles is less than 1 μm, the ceramic particles may fall off together with the matrix when worn, which may not contribute to the improvement of wear resistance. On the other hand, if it exceeds 150 μm, the toughness of the clad layer may be significantly reduced.
The particle size of the ceramic particles can be measured by a known method, for example, from the analysis result of the cross-sectional image of the clad layer by an optical microscope or an electron microscope.

[Mixing ratio of matrix (intermetallic compound alloy) and ceramic particles]
The compounding ratio of the intermetallic compound alloy and the ceramic particles may be appropriately set according to the characteristics of the metal member to be obtained.
For example, the ceramic particles are 10 to 60% by volume with respect to the clad layer (that is, the total of the intermetallic compound alloy and the ceramic particles).
If the ceramic particles are less than 10% by volume with respect to the clad layer, a sufficient strengthening effect of the clad layer may not be obtained. On the other hand, if the ceramic particles exceed 60% by volume with respect to the clad layer, the shape of the clad layer becomes unstable, and peeling or cracking may occur.

[Base material]
The base material is a target member coated by a clad layer, and examples thereof include a member formed of an iron-based alloy or the like. In general, iron-based alloys and the like have extremely low strength and hardness at high temperatures, but by being coated with a clad layer, the clad layer protects the base material from wear at high temperatures, so that it has abrasion resistance at high temperatures. , It is possible to provide a metal member having excellent strength, corrosion resistance and oxidation resistance.
The base material is not particularly limited as long as it is a metal material that can exert the effect of the present invention in combination with the clad layer, and is, for example, stainless steel (for example, JIS G4315: 2013), alloy tool steel (for example, JIS G4404:). 2006), selected from the group consisting of general structural rolled steel (eg JIS G3101: 2015), mechanical structural carbon steel (eg JIS G4051: 2009) and mechanical structural alloy steel (eg JIS G4053: 2008). Examples thereof include iron-based alloys or non-iron-based alloys selected from the group consisting of nickel, cobalt and titanium and their alloys.
More specifically, examples thereof include austenite-based cold heading stainless steel (SUS304) and alloy tool steel for hot dies of alloy steel for machine structure (SKD61), which are used in Examples.

[Use of metal parts]
The present invention provides an alloy (metal member) having higher high temperature strength (hardness) in applications where cemented carbide has been conventionally used, for example, tungsten carbide cobalt (WC-Co). be able to.
Further, the present invention has an alloy having higher oxidation resistance and corrosion resistance in applications in which tool materials and heat-resistant materials such as die steel, WC-Co cemented carbide, and Inconel have been conventionally used. Metal members) can be provided.

(2) Method for producing clad layer The method for producing a clad layer of the present invention includes Ni of 65 at% or more and 80 at% or less, Al of 4 at% or more and 15 at% or less, V of 4 at% or more and 15 at% or less, and 0 at%. The total weight of one or more 4th elements selected from the group consisting of Nb, Ta, Mo, Co, Cr, Si, W and Ti, which is 8 at% or less, and Ni, Al, V and the 4th element. On the other hand, an intermetallic compound alloy powder having a total alloy composition of B (boron) of 10% by weight or more and 1000% by weight or less and unavoidable impurities, and Ti, Zr, Hf, V, Nb, Ta, Cr. , Mo, W, Al and Y with a carrier gas and a substrate containing carbides, nitrides, carbonitrides, oxides, silices or boronic substances of one or more elements selected from the group. Including the step of forming a clad layer by irradiating the base material with heat source light while spraying on the base material.
The intermetallic compound alloy powder is characterized in that at least a part thereof is melted by receiving the heat source light and deposited on the base material together with the ceramic particles.

[Intermetallic compound alloy powder]
The intermetallic compound alloy powder used in the production method of the present invention includes Ni of 65 at% or more and 80 at% or less, Al of 4 at% or more and 15 at% or less, V of 4 at% or more and 15 at% or less, and 0 at% or more and 8 at% or less. 10 weight with respect to the total weight of one or more fourth elements selected from the group consisting of Nb, Ta, Mo, Co, Cr, Si, W and Ti, and Ni, Al, V and the fourth element. It consists of B (boron) of ppm or more and 1000% by weight or less, and unavoidable impurities. Such a powder can be produced, for example, by an atomizing method. Further, the average particle size of the intermetallic compound alloy powder may be 125 μm or less.

The intermetallic compound alloy powder is an alloy obtained by atomizing a molten metal (molten alloy) having a predetermined composition using elemental powders such as nickel powder, aluminum powder, vanadium powder, niobium powder and boron powder as raw material powders. It may be a powder. Further, it may be a mixed powder in which an elemental powder and an alloy powder are mixed.
Among these, atomized powder is preferable because an intermetallic compound alloy can be obtained more reliably and the hardness of the obtained composite material can be increased to the same level as that of a molten material.

[Ceramic particles]
Examples of the ceramic particles used in the production method of the present invention include the above-mentioned ceramic particles.
In the production of the clad layer, the ceramic particles are sprayed onto the substrate together with the intermetallic compound alloy powder. These may be jetted separately, or a mixed powder of ceramic particles and an intermetallic compound alloy powder may be jetted in advance.

The ceramic particles (raw material particles) used in the production method of the present invention preferably have a particle size of 20 μm or more and 150 μm or less.
If the particle size of the raw material particles is less than 20 μm, the powder may aggregate in the manufacturing process and the fluidity may decrease, resulting in unstable supply of laser light or the like to the heat source light irradiation unit. On the other hand, if it exceeds 150 μm, the powder injection nozzle may be clogged.
The particle size of the ceramic particles can be measured by a known method, for example, a method using a Fisher subsieving sizer.

[Manufacturing of clad layer]
Hereinafter, the method for producing the clad layer of the present invention will be described with reference to the drawings. The configurations shown in the drawings and the following description are exemplary and do not limit the scope of the invention.
The heat source light (energy source) for melting the alloy powder is not particularly limited, and examples thereof include laser light and arc light (TIG, MIG, etc.). Here, an example using laser light will be described.
FIG. 1 is an explanatory diagram of a method for manufacturing a clad layer according to an embodiment of the present invention.
This manufacturing method is a method using a laser metal deposition (LMD) device 11.
Specifically, while injecting the metal-metal compound alloy powder 6 and the ceramic particles 7 from the injection nozzle 5 onto the base material 2 together with the carrier gas, the base material 2 is irradiated with the laser beam 8 via the optical lens 9. By moving the injection nozzle 5 in the injection nozzle moving direction 10, a clad layer 3 is formed, and a metal member 1 having a base material 2 and a clad layer 3 covering the base material 2 is obtained.

That is, the laser beam 8 is irradiated toward the base material 2 from the center of the injection nozzle 5 that moves at a constant speed in the injection nozzle moving direction 10, and the intermetallic compound alloy powder 6 and the ceramic particles 7 are directed toward the irradiation point. A molten pool 4 is formed on the base material 2 in which the intermetallic compound alloy powder 6 which is injected together with the carrier gas and receives the laser beam 8 is melted and the ceramic particles 7 which are hardly melted are dispersed. The formed molten pool 4 is rapidly cooled as the injection nozzle 7 moves, and solidifies to form the clad layer 3.

The carrier gas not only functions as a transport medium (gas) for the intermetallic compound alloy powder and ceramic particles, but also functions as a shield gas that suppresses oxidation of the raw material components and the formed clad layer by the atmosphere. Therefore, as the carrier gas, an inert gas such as argon (Ar) gas or nitrogen (N) gas can be used.

The conditions for forming the clad layer 3 such as the supply speed of the intermetallic compound alloy powder and the ceramic particles and the laser output may be appropriately set according to the specifications of the apparatus to be used, the physical characteristics of the clad layer to be obtained, that is, the raw material components to be used, and the like. .. If the laser output is too low, the raw material components will not melt sufficiently, but if the laser output is too high, the base material components will be mixed in the clad layer, and the deposition area where the base material components are not substantially mixed. May not be obtained and the desired physical properties of the clad layer may not be obtained.
It is preferable that a diluted region in which the constituent components of both are mixed is formed at the interface between the base material and the clad layer. That is, the dilution region is a region in which the concentration of the base material component increases as it approaches from the clad layer side to the base material side, and the concentration of the component of the intermetallic compound alloy increases as it approaches from the base material side to the clad layer side. This diluted region strengthens the bond between the base material and the clad layer and imparts peel resistance to the metal member.

For example, the laser output is set to 1 kW or more and 1.6 kW or less, the supply rate of the intermetallic compound alloy powder is set to 5 g / min or more and 25 g / min or less, and 0 to 60% by volume of ceramic particles are supplied with respect to the intermetallic compound alloy powder. can do.
More specifically, at a laser output of 1.6 kW, the supply rate of the intermetallic compound alloy powder is 20 g / min or more and 25 g / min or less, and at a laser output of 1.2 kW, the supply rate of the intermetallic compound alloy powder is set. With a laser output of 15 g / min or more and 19 g / min or less and 1.0 kW, the powder supply rate can be 6 g / min or more and 12 g / min or less, and 10 to 60% by volume with respect to the intermetallic compound alloy powder. Ceramic particles can be supplied.

The above-mentioned LMD apparatus can precisely control the supply amount of the powder material and the input energy due to the laser irradiation, suppress the dissolution of the ceramic particles in the matrix as much as possible, and control the mixing of the base material components while controlling the clad layer. Is suitable for the method for producing a clad layer of the present invention.

[Formation of multilayer clad layer]
In the step of forming the clad layer, the multi-layered clad layer is formed by repeatedly irradiating the base material with heat source light such as laser light while injecting the intermetallic compound alloy powder and the ceramic particles together with the carrier gas onto the base material. It may be a step of forming.
For example, after the clad layer is formed on the base material by the above method, the clad layer 3 can be further laminated on the formed clad layer by the above method. As a result, the clad layers formed in layers can be integrated to form a thick clad layer.
As a result, it is possible to prevent the base material component from being mixed into the clad layer, it is possible to form a clad layer that can withstand wall thinning due to long-term wear, and a metal member having excellent high-temperature wear resistance is provided. can do.

[Heat treatment]
The method for producing a clad layer of the present invention may further include a step of heat-treating the clad layer at a temperature of 800 ° C. or higher and 1320 ° C. or lower.
The above method for producing a clad layer usually comprises a two overlapping phase structure consisting of an eutectoid L1 ₂ phase and an eutectoid structure of the L1 ₂ phase and a D0 ₂₂ phase, that is, Ni ₃ Al and Ni ₃ V. 2 No overlapping phase structure is formed. By subjecting such a clad layer to heat treatment, at least a part of the clad layer can have a two-overlapping phase structure or an eutectic structure of Ni ₃ Al and Ni ₃ V, and the clad layer can be homogenized. can.

The heat treatment can be performed using known equipment and methods.
The heat treatment temperature is, for example, 1320 ° C. or lower, preferably 1300 ° C. or lower, at which the intermetallic compound alloy of the matrix constituting the clad layer does not undergo a phase transition to the liquid phase.
Specifically, it is heated to the nickel solid solution single-phase region, and in the subsequent cooling process, it has a two-overlapping phase structure containing Ni ₃ Al and Ni ₃ V, or an eutectoid structure consisting of Ni ₃ Al and Ni ₃ V. The heat treatment temperature is preferably 800 ° C. or higher and 1320 ° C. or lower, because it can be obtained more reliably.
The heat treatment time (retention time) is preferably, for example, 0.5 hour to 24 hours.
Further, the heat treatment atmosphere is preferably a vacuum or an inert gas atmosphere such as argon gas in order to suppress oxidation of the clad layer by the atmosphere.

The present invention will be specifically described with reference to the following examples, but the present invention is not limited to these examples.
In the embodiment, a clad layer (building layer) is formed on a substrate by a laser metal deposition (LMD) method to obtain a sample of a metal member, further heat-treated, and the samples before and after the heat treatment are observed and observed. Evaluation was performed.

[Preparation of sample]
Using the following base material, intermetallic compound alloy powder and ceramic particles, the length = about 60 mm, width = about 5 mm, height = about 1 on the base material under the following conditions by LMD as shown in FIG. A clad layer of about 2.5 mm (single layer) was formed, and samples of three types of metal member WC, metal member VC, and metal member NbC were obtained.
(Intermetallic compound alloy powder)
A metal raw material prepared to have an alloy composition of 75.0 at% Ni, 9.0 at% Al, 13.0 at% V, 3.0 at% Nb, 0.005 wt% B is powdered by an atomizing method to 125 μm or less. By classifying into the particle size of, an intermetallic compound alloy powder (NAV-3Nb) as a binder was obtained.

(Ceramic particles)
WC particles (particle size 53-150 μm)
VC particles (particle size 75-150 μm)
NbC particles (particle size ~ 125 μm)

(Base material)
Material: SUS304 (18 to 20% by mass Cr, 8 to 10.5% by mass Ni, residual Fe)
Dimensions: Length = 60mm, Width = 20mm, Thickness: 10mm

(LMD condition)
Laser output: 1.6kW
Laser operation speed: 5 mm / sec
Laser beam diameter: 5 x 5 mm
Carrier gas: Argon (Ar) gas, sprayed from the injection nozzle at about 5 L / min Supply rate of powder and particles: NAV-3Nb 17.4 g / min
WC 20.4g / min
VC 9.6g / min
NbC 12.0g / min
Powder and particles used: Metal member WC (NAV-3Nb + WC)
Metal member VC (NAV-3Nb + VC)
Metal member NbC (NAV-3Nb + NbC)

[Heat treatment of sample]
Further, the sample of each metal member was heat-treated under the following conditions.
Processing temperature: 1280 ° C
Processing time: 5hr
Atmosphere: Vacuum cooling: Furnace cooling (natural cooling in the furnace)

[Observation of appearance of clad layer]
FIG. 2 is an external photograph of the clad layer of each metal member, the upper figure is a view seen from a direction perpendicular to the forming direction of the clad layer, and the lower figure is a cross-sectional view of the clad layer.
According to FIG. 2, it can be seen that a good clad layer having no surface defects or internal voids is formed in each case. Further, it can be seen that in the metal member VC and the metal member NbC, the VC particles and the NbC particles of the ceramic particles are uniformly dispersed in the NAV-3Nb of the matrix, respectively. On the other hand, in the metal member WC, it can be seen that the WC particles are weight segregated in the lower layer (base material side) of the clad layer probably because the density difference between the NAV-3Nb of the matrix and the WC particles of the ceramic particles is large.

[SEM observation of cross section of clad layer]
FIG. 3 is an SEM photograph of the cross section (deposited region) of the matrix of the clad layer of each metal member before and after the heat treatment, the upper part is before the heat treatment, the lower part is after the heat treatment, and the upper right photograph of each photograph is each photograph. It is an enlarged photograph of. However, only the metal member WC in which weight segregation was observed in the appearance observation shows an enlarged photograph of the upper region and the central to lower region of the photograph after the heat treatment.
According to FIG. 3, in the metal member VC and NbC after the heat treatment, a rectangular structure was observed in the clad layer, and the two overlapping phase structures (initially analyzed L1 ₂ phase, L1 ₂ phase and D0 ₂₂ phase) were observed by the heat treatment. It can be seen that a microstructure consisting of a heat-treated structure) is formed.
On the other hand, in the metal member WC after the heat treatment, a two-overlapping phase structure is observed in the upper part of the clad layer having few WC particles, while a rounded initial phase structure is observed in the lower part of the clad layer in which WC particles are present at high density. Is observed, and it can be seen that it is difficult to form a two-overlapping phase structure even by heat treatment due to weight segregation.
As described above, according to the experimental results, when the ceramic particles are VC and NbC, it is easier to form a two overlapping phase structure than in the case of WC, and the ceramic particles contain elements (Nb and V) constituting the matrix. It can be seen that if the particles contain elemental carbides, nitrides, carbonitrides, oxides or borides, a two-layered phase structure is likely to be formed by heat treatment.

[EPMA composition analysis of clad layer]
Using an electron probe microanalyzer (EPMA), elemental analysis of the matrix portion of the clad layer of each metal member before and after the heat treatment was performed. However, only the metal member WC in which weight segregation was observed in the appearance observation was analyzed separately in the upper region and the central to lower region.
The results obtained are shown in Table 1.

According to Table 1, the matrix portion of the clad layer of each metal member contains elements derived from the base material SUS304 and the ceramic particles, which are not contained in the test material as the intermetallic compound alloy powder. Recognize. Further, regarding Cr and Ni, there is almost no difference in the contents before and after the heat treatment. That is, the contents of Cr and Ni, which are the base material components mixed in the clad layer by melting a part of the base material at the time of forming the clad layer, hardly change even by the heat treatment after becoming a solid state. That is, it is considered that the mixing amount of Cr and Ni is determined by the formation conditions of the clad layer.

Further, in the same manner, elemental analysis of the ceramic particle portion of the clad layer of each metal member after the heat treatment was performed using EPMA.
The results obtained are shown in Table 2.

According to Table 2, the ceramic particle portion of the clad layer of each metal member contains elements derived from the test material as the base material SUS304 and the intermetallic compound alloy powder, which are not contained in the ceramic particles. I understand. Table 2 shows the analysis results after the heat treatment, and it is considered that there is almost no difference in the content before and after the heat treatment, as in the matrix portion.

[EPMA mapping of clad layer]
Using EPMA, mapping of each element was performed for the matrix portion of the clad layer of each metal member after heat treatment. The elements to be analyzed were Ni, Al, V, Nb, Fe, Cr and C, and W only for the metal member WC.
4 to 6 are EPMA mappings of each element for the matrix portion of the clad layer after heat treatment of the metal member WC, the metal member VC and the metal member NbC, respectively. In the figure, "SEI" indicates a secondary electron image, and "COMPO" indicates a backscattered electron composition image.
According to FIG. 4, no two overlapping phase structure is confirmed in the clad layer of the metal member WC, and it can be seen that the elements constituting the carbide are C, V, W and Nb.
According to FIGS. 5 and 6, the formation of a two overlapping phase structure is confirmed in the metal member VC and the metal member NbC, and it can be seen that Al is present in the initial analysis and V is present in the channel. Further, it can be seen that both Fe and Cr mixed from the base material are present in the channel.

[Phase identification by X-ray diffraction]
Using X-ray diffraction, phase identification of the clad layer of each metal member after heat treatment was performed.
FIG. 7 is an X-ray diffraction diagram of the clad layer before and after the heat treatment of the metal member WC, the metal member VC, and the metal member NbC.
It can be seen that in the clad layer of the metal member WC, a Ni solid solution phase (Nis.s.) is present before the heat treatment, and a Ni solid solution phase and a Ni ₃ Al phase (Ni ₃ Al) are present after the heat treatment. No two overlapping phase structure is confirmed in the clad layer of the metal member WC.
It can be seen that the Ni solid solution phase and the Ni ₃ Al phase are present in the clad layer of the metal member VC before the heat treatment. The formation of a two-overlapping phase structure is confirmed on the metal member VC.
It can be seen that the Ni ₃ Al phase and the Ni ₃ V phase (Ni ₃ V) are present in the clad layer of the metal member NbC after the heat treatment. The formation of a two-overlapping phase structure is confirmed on the metal member NbC.

[Hardness distribution]
Using a Vickers hardness tester, the Vickers hardness from the vicinity of the formation surface of the clad layer of each metal member after the heat treatment to the vicinity of 2.5 mm was measured. The Vickers hardness test was measured by cutting the sample by electric discharge machining so that the cross section of the clad layer appeared, buffing or electrolytic polishing, and then pressing an indenter against the cross section of the clad layer.
FIG. 8 is a diagram showing the Vickers hardness distribution in the vicinity of the surface of the clad layer before and after the heat treatment of the metal member WC, the metal member VC, and the metal member NbC.
According to FIG. 8, it can be seen that the clad layer of any of the metal members has a hardness of about 450 HV before the heat treatment. Further, although the hardness is slightly increased by the heat treatment, it can be seen that there is no great difference in the hardness distribution before and after the heat treatment.

1: Metal member 2: Base material 3: Clad layer 4: Molten pool 5: Injection nozzle 6: Intermetallic compound alloy powder 7: Ceramic particles 8: Laser light 9: Optical lens 10: Injection nozzle movement direction 11: Laser metal device Position device

Claims (3)

The total of Ni of 65 at% or more and 80 at% or less, Al of 4 at% or more and 15 at% or less, V of 4 at% or more and 15 at% or less, Nb of more than 0 at% and 8 at% or less, and Ni, Al, V and Nb. From the group consisting of intermetallic compound alloy powder having a total alloy composition of B (boron) of 10 wt ppm or more and 1000 wt ppm or less and unavoidable impurities with respect to the weight, and V, Nb and W. A clad layer is formed by irradiating a substrate with heat source light while injecting ceramic particles, which are carbides of one or more selected elements and having a particle diameter of 1 μm or more and 150 μm or less, onto the substrate together with a carrier gas. Including the forming step
The mixing ratio of the ceramic particles to the clad layer is 10 to 60% by volume.
A method for producing a clad layer, wherein at least a part of the intermetallic compound alloy powder is melted by receiving the heat source light and deposited on the base material together with the ceramic particles. In the step of forming the clad layer, the base material is irradiated with heat source light a plurality of times while injecting the intermetallic compound alloy powder and the ceramic particles together with the carrier gas onto the base material to form a multilayer clad layer. The manufacturing method according to claim 1 , which is a step of performing. The production method according to claim 1 or 2 , further comprising a step of heat-treating the clad layer at a temperature of 800 ° C. or higher and 1320 ° C. or lower.

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