KR100489372B1 - Composite Coatings Containing Quasicrystalline Phases By Thermal Spray Technique And Method For Making The Same - Google Patents

Abstract

The present invention relates to a coating layer of a composite material containing an aluminum-based quasi-crystalline phase for improving the friction and wear characteristics of the machine and a method of manufacturing the same.

The present invention features a coating layer of a composite material containing an aluminum-based semi-crystalline alloy powder and at least one of a metal, an intermetallic compound, a ceramic, a summ and a polymer powder on a metal or intermetallic compound matrix.

In addition, the present invention, by mixing the aluminum-based semi-crystalline alloy powder with at least one of metal, intermetallic compound, ceramic, summit and polymer powder to prepare a mixed powder, and spray coating the mixed powder to form a coating layer Characterized in that it comprises a step.

Description

Semi-crystalline phase-containing composite coating layer by powder spraying method and its manufacturing method {Composite Coatings Containing Quasicrystalline Phases By Thermal Spray Technique And Method For Making The Same}

The present invention relates to a composite coating layer containing a semi-crystalline phase by the powder spraying method and a method for manufacturing the same. Particularly, in order to improve friction and wear characteristics of a machine, an aluminum-based quasi-crystalline alloy powder having a predetermined volume fraction and The present invention relates to a composite coating layer containing a metal, a ceramic, a summit, a plastic powder, and a method of manufacturing the same.

Engineeringly available materials such as metals, ceramics, cermets, polymers and the like have been used in numerous applications because of their physical, mechanical and electrical properties, manufacturability and cost advantages. However, these materials have disadvantages such as low surface hardness, high coefficient of friction and low oxidation resistance.

Quasicrystals exhibit structural and physical characteristics that are different from crystals and amorphous phases, and have five, eight, ten, and twelve rotational symmetry and quasi-periodic long-range translation rules. Quasi-crystalline phases include quasi-crystalline analogous (approximant) phases. Many crystal phases are formed around the composition in which the semi-crystals are formed. These crystal phases coexist with quasi-crystalline phases in many cases and are structurally similar to and related to quasi-crystal phases. These crystal phases are called quasi-crystal-like structures. Similar structure means that the atomic arrangement of these crystal phases is similar to the quasi-crystal locally.

Quasicrystals were first discovered in 1982 by Sechtmann in Al-Mn alloy systems and are new materials with structural and physical properties that are different from crystals or amorphous materials. It has five, eight, ten and twelve rotationally symmetrical and quasi-periodic long-range translation rules. These alloys change into equilibrium crystal phases when heated to metastable phases.

Al-Li-Cu, Al-Cu-Fe, Al-Ni-Co, Al-Cu-Co, Al-Pd-Mn alloys are thermodynamically stable and can be manufactured by conventional casting methods rather than rapid solidification methods. Early research focused on the understanding and thermodynamic stability of quasi-crystalline atomic structures, but recently the interest in mechanical and physical properties. Quasi-crystal has high strength, low thermal conductivity, oxidation resistance, corrosion resistance, and low coefficient of friction.

Kang is reported to have a value between 0.1 and 0.2 in Al-Cu-Fe, Al-Cu-Fe-Cr and Al-Cu-Fe-Cr-Si quasi-crystalline coatings through a scratch test, one of friction tests. (Ref., SS Kang, JM Dubois and J. von Stebut, J. Mater. Res., 8 (10), (1993) p.2471.). Recently, the coefficient of friction has been reported to vary according to the composition and structural dependence of the semi-crystalline phase coated using the pin-on-disc method (Ref., RP Matthew, CI Lang and D. Shechtman, Tribology Letters, 7 , (1999) p. 179 .; CI Lang, D. Shechtman, and EJ Gonzales, Bull.Mat.Sci., 22 (3), 189 (1999) .; CI Lang, DJ Sordelet, MF Besser, D. Shechtman, FS Biancaniello and EJ Gonzales, J. Mater. Res., 15 (9), (2000) p. 1894.).

In addition, Dubois et al. U.S. Patent 5,652,877 (July 29, 1997) to U.S. Patent No. 5,652,877 discloses a composition range and application of a semi-crystalline alloy.

On the other hand, the semi-crystalline coating layer is excellent in the friction characteristics as described above, but the use of the semi-crystal as an industrial use is limited because of brittleness.

The inventors of the present invention suggest that the semi-crystal is a surface coating material that can increase the oxidation resistance, friction and abrasion resistance of existing mechanical parts, and has low surface energy, low thermal conductivity, low electrical conductivity, oxidation resistance, high hardness, low density, and metal. Considering the fact that it has a coefficient of thermal expansion similar to that of the above, various studies and experiments have led to the discovery of a composite coating containing a semi-crystalline phase which can lower the surface energy and thermal conductivity.

Accordingly, the present invention has been made in view of the problems of the prior art, and its object is to reduce the surface energy and thermal conductivity, and to improve the oxidation resistance and friction and wear characteristics, and to maintain a certain volume on a metal or intermetallic compound base. It is to provide a composite coating layer using a mixed material of aluminum-based quasi-crystalline phase of a fraction and a metal, ceramic, summit, and polymer powder, and a method of manufacturing the same.

Such semi-crystalline powder composite coating material can increase the hardness, low surface energy, low thermal conductivity, low coefficient of friction, oxidation resistance, thermal stability, etc. Through this, wear resistance, oxidation resistance, heat resistance such as automobile, airplane, ship, and bio materials It can be widely used in many industrial applications where the back light is required.

In order to achieve the above object, the present invention is characterized in that the metal or intermetallic compound is formed by spray coating the aluminum-based semi-crystalline alloy powder and at least one mixed powder of metal, intermetallic compound, ceramic, summit and polymer powder. A semicrystalline phase-containing composite coating layer by a spraying method is provided.

In addition, the present invention is to prepare a mixed powder by mixing the aluminum-based semi-crystalline alloy powder with at least one of metal, intermetallic compound, ceramic, summit and polymer powder, and by spray coating the mixed powder metal or intermetallic compound It provides a method for producing a semi-crystalline phase-containing composite coating layer by a powder spraying method comprising the step of forming a coating layer on the base.

The aluminum quasicrystalline phase used in the present invention has the following composition. A + b + c + d + e = 100 in Al _a M _b N _c X _d I _e , each of a ≧ 50%, 8 ≦ b ≦ 25, 5 ≦ c ≦ 20, 0 ≦ d ≦ 15, 0 It is represented by the atomic weight ratio of ≤ e ≤ 2. M represents one of Cu and Co, N represents one or more of Fe, Mn, Ni, Ru, Os, Mo, V, Mg, Zn, and X represents Cr, Si, Be, B, Y And one of the rare metal elements. I represents an impurity contained in a gas spray or coating process such as oxygen or nitrogen.

The semi-crystalline powder used in the present invention can be made into a homogeneous and fine powder by a general casting method having a relatively slow cooling rate or a gas spray method with a high cooling rate. As quasi-crystalline materials of various compositions are made of powder, they can be used as coatings on various base metals.

For example, in order to obtain a coating layer having a low coefficient of friction and low thermal conductivity, arc spraying and plasma spraying may be used in air or vacuum. This is because a coating layer having a high porosity can be obtained by these spray methods. In order to prepare a coating material including a material such as metal, ceramic, polymer, mixed powder may be used.

This mixed powder can be prepared by using a mobile combustion spray gun such as Sulzer-Metco's 5P class. By using HVOF thermal spraying, coatings with low porosity can be produced, which is suitable for materials requiring oxidation and wear resistance. And by using a supersonic jet torch, the porosity of the coating can be lowered to near zero. Supersonic jet torches can deposit the powders of the invention at speeds between Mach 6 to Mach 14.

Al-Cu-Fe, Al-Cu-Fe-Be, Al-Cu-Fe-Cr, Al-Cu-Fe-Cr-B, Al-Cu-Fe-Si, Al-Ni -Co-Si or the like was used.

In addition, in order to supplement the brittleness of the semi-crystalline coating layer and optimize wear resistance, adding 20% by weight of Sn, which is a ductile material, to the semi-crystalline powder reduces the volume reduction rate as compared with the Al-Cu-Fe plasma coating material. When a low surface energy, low thermal conductivity and low coefficient of friction are required on the surface of a metal substrate, and when it is desired to increase hardness, wear resistance, and oxidation resistance, a soft metal material such as aluminum (Al) and a semicrystalline powder may be mixed. .

In order to reduce the surface energy and friction coefficient of ceramic coating materials, ceramic materials and semi-crystalline powders can be mixed.In order to increase the hardness and lower the friction coefficient of plastic coating materials, plastic materials and semi-crystalline materials can be mixed. have.

In consideration of environmental friendliness, tungsten carbide (WC) spray coating is gradually being replaced by chromium (Cr) electrocoating. Since WC is brittle, ductile materials such as Co, Ni, and Fe are mixed in a mass ratio of about 8 to 28%. The WC / Co coating layer deposited by the thermal spraying method has high hardness and very good wear characteristics, but has a disadvantage in that the wear of the counterpart cannot be controlled. Therefore, the inclusion of the quasi-crystalline phase having a volume fraction of about 30% or less having a low surface energy can reduce the wear of the counterpart without deteriorating the friction and wear characteristics.

As described above, the composite coating material containing the semi-crystalline powder of the present invention can increase the hardness, low surface energy, low thermal conductivity, low coefficient of friction, oxidation resistance, thermal stability, and the like, such as automobiles, airplanes, ships, and biomaterials. It can be widely used in many industrial applications such as wear resistance, fire resistance, heat resistance, and the like are required.

If the present invention will be described in detail based on the Examples as follows, the present invention is not limited to the Examples.

<Example>

In the experiments below, the coating layers were prepared by plasma arc spray and HVOF methods in order to compare the friction and wear of the semi-crystalline coating layer and the ceramic coating layer. To present.

First, Al, Cu, Fe, Cu-Be, Fe-B, Cr, Ni, Co, and Si raw materials of commercial purity (99.8 wt%) are subjected to pretreatment such as pickling and drying, and the target composition is Al ₆₅ Cu ₂₅ Fe. ₁₀ , Al ₅₅ Cu _25.5 Fe _12.5 Be ₇ , Al ₇₀ Cu ₁₀ Fe ₁₃ Cr ₇ , Al ₆₉ Cu ₁₀ Fe ₁₃ Cr ₇ B ₁ , Al ₅₀ Cu ₂₀ Fe ₁₅ Si ₁₅ , Al ₇₀ Ni ₁₃ Co ₁₃ Si ₄ After the high frequency induction was dissolved in 30 Kg units, quasi-crystalline powders were prepared by gas spraying under a nitrogen atmosphere. In addition, a composite powder was prepared in the same manner by adding the prepared semi-crystalline alloy and WC, Co, Sn and the like. At this time, the nozzle diameter was 4 mm, the temperature of the melt just before spraying was 1200 ℃, and the gas was sprayed using nitrogen gas.

Stainless steel of size 100 × 100 × 3 (mm) was subjected to pickling and drying followed by grit blasting to give a surface roughness (8 to 10 μm) suitable for thermal spraying. The gas-sprayed semi-crystalline powder was classified and a powder having a particle size of 75 to 38 μm was used as a thermal spraying material. In order to remove the moisture of the powder, it was dried for at least 48 hours in a dryer maintained at 120 ℃. Plasma sprays used a GC800 (2PS) gun model and HVOF sprays used a DJ1000S (Metco) gun model.

Scanning electron microscopy and X-ray diffractometer were used to analyze the microstructure and coagulation characteristics of the spray coating layer, and the thickness, surface roughness, porosity, and Vickers microhardness of the coating layer were measured. All measurements were made at least 10 times to obtain the arithmetic mean of the values excluding the maximum and minimum values.

In order to compare ZrO ₂ and Cr ₂ O ₃ , the coating layer, which is a conventional ceramic coating material, was prepared on the same metal substrate by plasma spraying, and the friction and wear characteristics were investigated.

The semi-crystal coated stainless steel (100 × 100 × 3 (mm)) was cut to 30 × 40 mm using a high speed cutter (ISOMET 4000), and then mechanically polished and buffered to have a surface roughness of 0.2 μm or less. These specimens were prepared and subjected to friction and wear tests. The experimental standard conditions were 80 N of load, 0.56 m / s of sliding speed, and 560 m of sliding distance. The counterpart was a chrome coated cast iron with a disc 12 mm in diameter. The average thickness of the chromium coating is about 160 μm and the surface roughness ranges from about 0.12 to 0.16 μm. Each of these experiments was done three times.

The data obtained as a result of the above various experiments are collectively shown in FIGS. 1 to 11.

Figure 1 shows the X-ray diffraction of the semi-crystalline coating layer. The abscissa is the diffraction angle 2θ and the ordinate is the diffraction intensity.

As shown, there are icosahedral and beta (β) phases in the Al-Cu-Fe-Be plasma coating layer and icosahedral and decoction in the Al-Cu-Fe-Cr-B plasma coating layer. There is a decagonal phase and there is a decagonal phase in the Al-Ni-Co-Si plasma coating layer. In the Al-Cu-Fe-Si plasma coating layer, a quasi-crystal-like structure (approximant) exists.

2A and 2B are X-ray diffraction graphs of the WC / 12Co + 15% Al-Cu-Fe-Si composite coating layer formed by the HOVF method and the Al-Cu-Fe + 20% Sn composite coating layer formed by the plasma coating method. In the WC / 12Co + 15% Al-Cu-Fe-Si composite coating layer, WC phase, W ₂ C phase and Co are present, and in the Al-Cu-Fe + 20% Sn composite coating layer, icosahedral, Sn Phase and beta (β) Al ₅₀ (Cu, Fe) ₅₀ phase are present.

3A and 3B show scanning electron microscope (SEM) photographs of cross sections of Al—Ni—Co—Si quasi-crystalline coating layers deposited by plasma spraying and HVOF spraying, respectively. The plasma coating layer of FIG. 3A shows a lamellar structure and the pore size distribution is not uniform and has a high pore fraction. The microstructure of the HVOF coating of Figure 3b has a low pore fraction. In addition, the pore size is small and uniformly distributed.

4A and 4B show scanning electron micrographs of cross sections of WC / 12Co + 15% Al-Cu-Fe-Si and Al-Cu-Fe + 20% Sn composite coating layers deposited by plasma spraying and HVOF spraying. . 4A shows that the distribution of the quasicrystalline phase in the WC / 12Co matrix is relatively very uniform. In the coating layer formed by HVOF spraying, the quasi-crystalline phase fills the porosity during the spraying process, and the pore fraction of the coating layer is very low, less than 1.5%. As shown in FIG. 4B, it can be seen that Sn is present together with the Al-Cu-Fe quasi-crystalline phase and the beta (β) phase, and the pore fraction decreases due to the solidification of Sn in the quasi-crystalline phase.

5 is a table showing porosity and hardness of the semi-crystalline coating layer deposited by plasma spray and HVOF spray. Referring to FIG. 5, it was slightly different depending on the alloy composition, but had 11.83% pore fraction in Al-Ni-Co-Si plasma coating and 6.36% pore fraction in HVOF coating. The Al-Cu-Fe-Si plasma coating has a 9.9% pore fraction and the HVOF coating has a 1.4% pore fraction. The above difference in pore fraction is due to the fact that in plasma coating, the powder in the semi-molten state can be found due to the large temperature gradient in the powder. This is because the flame of the HVOF is as long as 20 cm while the flame of the plasma is as short as 3 cm. Compared to the hardness, the plasma coating layer shows a value of about 16 lower, because the plasma coating layer has somewhat more pores and the tissue is less dense than the HVOF coating layer.

Figure 6 shows the friction coefficient value of the semi-crystalline coating layer according to the additive element in the aluminum-based alloy. Experimental results include Al-Cu-Fe-Be, Al-Cu-Fe, Al-Cu-Fe-Be-B, Al-Cu-Fe-Cr ₁₀ , Al-Cu-Fe-Cr ₇ , Al-Cu-Fe It can be seen that the friction coefficients are shown in the order of -Cr-B.

7 is a graph showing the results of measuring the coefficient of friction coefficient of the ceramic coating layer and Al-Ni-Co-Si semi-crystalline coating layer used in the airplane and automotive industry at room temperature (■) and 450 ℃ (□), respectively.

7 shows the coefficient of friction according to the moving distance of the disk under standard conditions after the plasma coating and HVOF coated specimens were polished to 0.2 μm or less. When measured at room temperature (■) in a stable region of 100 ~ 570 m it has a constant value of 0.43 for the plasma-coated specimens, 0.37 for the HVOF-coated specimens.

Comparing the friction coefficients with other materials under the same standard conditions, Al alloys and stainless steels had values of 0.5 to 0.6. Thus, it can be seen that the semi-crystalline coating has a low coefficient of friction. In addition, the partially stabilized ZrO ₂ tested at the same standard conditions had a value of 0.8 and Cr ₂ O ₃ had a value of 0.63.

8 is a graph showing the coefficient of friction coefficient of the Al-Ni-Co-Si quasi-crystalline coating layer compared to the ceramic coating layer in the dry and lubricating oil state. In FIG. 8, the plasma coating and the HVOF coated specimens are polished to 0.2 μm or less as shown in FIG. Afterwards, the coefficient of friction is shown according to the moving distance of the disk under standard conditions. In Figure 8 it can be seen that the overall coefficient of friction in lubricating oil conditions is lower than the coefficient of friction in dry conditions and the semi-crystalline coating layer is better than the ceramic.

Friction coefficient values were measured according to the load, sliding speed, and temperature influencing the friction coefficient. Al-Ni-Co-Si quasi-crystalline plasma coating has a constant value of 0.43 depending on the change of load and a constant value of 0.43 to 0.45 according to the change of temperature. However, as the sliding speed increases from 0.14 m / s to 0.56 m / s, the coefficient of friction decreases from 0.52 to 0.43.

In addition, HVOF coating has a constant value of 0.36 depending on the change of load and a constant value of about 0.36 to 0.37 according to the change of temperature. However, as the sliding speed increases from 0.14 m / s to 0.56 m / s, the coefficient of friction decreases from 0.47 to 0.36. In high speed test conditions with a sliding speed of 0.56 m / s, the reduction of the friction coefficient causes the change of the contacting surface by generating frictional heat during the friction test.

Therefore, the result of the reduction of the friction coefficient under the high-speed experimental conditions as described above is generally known as a local increase in temperature, flash temperature, which is considered as a factor. In semi-crystalline coatings, it can be seen that there are constant coefficients of friction for variables such as load, temperature and sliding speed. These values are within certain standard deviations.

9 is a graph showing the wear rate of the semi-crystalline coating layer compared to the ceramic coating layer at 450 ℃, Al-Ni-Co-Si HVOF semi-crystalline coating layer shows a wear rate similar to the Cr ₂ O ₃ plasma coating layer.

FIG. 10 is a graph showing the wear rate of the WC / 12Co + 15% Al-Cu-Fe-Si quasi-crystalline composite coating layer deposited by HVOF spray compared to the WC / 12Co coating layer. The WC / Co coating layer deposited by the thermal spraying method has high hardness and very good wear characteristics, but has a disadvantage in that the wear of the counterpart cannot be controlled. As shown in FIG. 10, at 25 ° C., the wear rate of the WC / Co coating layer is very low, but the wear rate of the counterpart material is relatively high, so it is very difficult to use it as an actual industrial material. In comparison, the WC / 12Co + 15% Al-Cu-Fe-Si quasi-crystalline composite coating layer containing a semicrystalline phase shows that the wear rate of the counterpart material is significantly reduced while maintaining the wear rate of the coating layer. Rather, it shows that both the wear characteristics of the composite coating layer and the coating layer of the counterpart material are improved.

FIG. 11 is a graph showing wear rates of Al-Cu-Fe / Sn composite coating layers and counterparts including 12, 20, and 30 fractions of Sn deposited by plasma spraying as compared to Al-Cu-Fe semi-crystalline coating layers. The wear rate of the counterpart is hardly affected by the composition, but the volume of the coating layer is considerably reduced by the addition of Sn, compared to the Al-Cu-Fe coating layer, which is the best wear in the coating of Al-Cu-Fe + 20Sn. Demonstrate that a property can be obtained.

As can be seen from this example, when aluminum-based semi-crystalline alloy powder and metal, ceramic, summit, plastic powder, etc. are mixed and used as coating materials, friction and abrasion characteristics can be complemented to form a more efficient composite coating. Giving.

As described above, in the present invention, aluminum-based semi-crystalline alloy powder and metal, ceramic, cermet, and plastic powder are mixed to provide excellent wear resistance, heat resistance, corrosion resistance, electrical conductivity shielding, cemented carbide, and excellent resistance in the temperature range of 25 to 500 ° C. An excellent composite coating layer having properties such as oxidizing property can be obtained.

In particular, since the surface temperature on the substrate during spraying can be controlled within 150 ° C, it has an operating characteristic that can be extended to paper products. Surface coating materials, such as cookware, electric irons, rolls for making paper or glass, and plastic products that require non-sticking properties because of low coefficient of friction, wear resistance, and non-sticking properties It can be used as a mold.

The tribological properties of the semi-crystalline coatings were measured at 450 ° C as well as at room temperature, with lower coefficients of friction and lower wear rates at 450 ° C than at room temperature. Therefore, the semi-crystalline coating material can be used as a potential coating material for piston rings in automobile engines in the future, and it is expected that the use of this can increase the efficiency of automobile engines.

In the above, the present invention has been described with reference to specific preferred embodiments, but the present invention is not limited to the above-described embodiments and the general knowledge in the art to which the present invention pertains without departing from the spirit of the present invention. Various changes and modifications will be possible by those who have the same.

1 is an X-ray diffractometer graph of Al-Cu-Fe-Be, Al-Cu-Fe-Cr-B, Al-Cu-Fe-Si, Al-Ni-Co-Si quasi-crystalline coating layer,

2A and 2B are X-ray diffraction graphs of WC / 12Co + 15% Al-Cu-Fe-Si and Al-Cu-Fe + 20% Sn composite coating layers,

3a and 3b are scanning electron micrographs of the cross section of the Al-Ni-Co-Si quasi-crystalline coating layer deposited by the plasma spray and HVOF spray,

4A and 4B are scanning electron micrographs of cross sections of WC / 12Co + 15% Al-Cu-Fe-Si and Al-Cu-Fe + 20% Sn composite coating layers deposited by plasma spray and HVOF spray;

5 is a table showing porosity and hardness of Al-Ni-Co-Si and Al-Cu-Fe-Si quasi-crystalline coating layers deposited by plasma spraying and HVOF spraying;

6 is a graph showing the coefficient of friction of the quasi-crystalline coating layer according to the additive element in the aluminum-based alloy,

7 is a graph showing the coefficient of friction of the Al-Ni-Co-Si semi-crystalline coating layer under the same conditions of dry conditions at temperatures of 25 and 450 ℃ compared to the Cr ₂ O ₃ ceramic coating layer used in the airplane and automotive industry,

8 is a graph showing the coefficient of friction of the Al-Ni-Co-Si quasi-crystalline coating layer under the same conditions of 25 ℃ compared to the Cr ₂ O ₃ ceramic coating layer in dry and lubricating oil,

9 is a graph showing the wear rate of the semi-crystalline coating layer compared to the Cr ₂ O ₃ ceramic coating layer at 450 ℃,

10 is a graph showing the wear rate of the WC / 12 Co + 15% Al-Cu-Fe-Si quasi-crystalline composite coating layer deposited by HVOF spray compared to the WC / 12Co coating layer,

FIG. 11 is a graph showing the wear rate of an Al-Cu-Fe / Sn composite coating layer including 12, 20, and 30 fractions deposited by plasma spraying as compared to the Al-Cu-Fe semi-crystalline coating layer.

Claims (6)

A powder obtained by spray coating a mixed powder obtained by mixing an aluminum-based semi-crystalline alloy powder with at least one powder selected from metal, intermetallic compound, ceramic, summit and polymer powder on a metal or intermetallic compound matrix. Semi-crystalline phase-containing composite coating layer by thermal spraying method. Preparing a mixed powder by mixing an aluminum-based semi-crystalline alloy powder with at least one of metal, intermetallic compound, ceramic, summit and polymer powder, The method of manufacturing a semi-crystalline phase-containing composite coating layer by a powder spraying method comprising the step of thermally coating the mixed powder to form a coating layer on a metal or intermetallic compound matrix. According to claim 2, wherein the aluminum-based semi-crystalline alloy is Al-Cu-Fe, Al-Cu-Fe-Be, Al-Cu-Fe-Cr, Al-Cu-Fe-Cr-B, Al-Cu-Fe- Method for producing a semi-crystalline phase-containing composite coating layer by a powder spray method, characterized in that any one of Si, Al-Ni-Co-Si. The method of claim 2, wherein the spray coating method is any one of a plasma spraying method and a HVOF spraying method. The method of claim 2, wherein the aluminum-based semicrystalline alloy powder is an Al-Cu-Fe semicrystalline alloy powder, and the metal powder is Sn. The method of claim 2, wherein the aluminum semi-crystalline alloy powder is an Al-Cu-Fe-Si semi-crystalline alloy powder, and the summit powder is WC / Co.