A rare earth element-containing tungsten alloy wire and a preparation method and application thereof

Abstract

The application discloses a tungsten alloy wire containing rare earth elements and a preparation method and application thereof. According to mass percentage, the tungsten alloy wire containing rare earth elements comprises the following components: Y 0-5%, Ce 0-5% and the balance of W (containing inevitable impurities). The preparation method of the tungsten alloy wire containing rare earth elements comprises the following steps: S1, taking raw materials according to a formula, and obtaining raw materials by pre-alloying powder or mechanical mixing powder; S2, performing additive manufacturing on the raw materials; and S3, performing multi-pass rotary swaging on tungsten alloy blanks obtained through the additive manufacturing, and then performing drawing to obtain the tungsten alloy wire containing rare earth elements. The tungsten alloy wire containing rare earth elements has the characteristics of good uniformity of organizational structure, high strength and good high-temperature processing performance. In addition, the preparation method is simple and controllable, is suitable for industrial production, and can be widely applied to solar silicon wafer cutting and the like.

Description

Technical Field

[0001] This invention belongs to the field of new materials and advanced manufacturing technology, specifically relating to a tungsten alloy wire containing rare earth elements, its preparation method, and its application. Background Technology

[0002] Tungsten alloys, primarily based on tungsten, the metallic element with the highest melting point, possess excellent properties such as high melting point and high strength. Furthermore, tungsten alloy wires exhibit good flexibility even at diameters less than 1 mm, making them suitable for cutting solar-grade monocrystalline and polycrystalline silicon. However, existing tungsten alloy wires still have some drawbacks. These include the high hardness of the wires, which complicates processing and makes manufacturing extremely difficult, hindering large-scale mass production. Additionally, the tensile strength of conventional tungsten wires rarely exceeds 4000 MPa, offering no significant advantage over widely used high-carbon steel wires, leading to a substantial increase in operating costs.

[0003] Existing tungsten alloy filaments are relatively brittle and easily break under external forces. During the cutting process of solar silicon wafers, improper handling or impacts can cause these filaments to fracture, severely impacting product yield. Furthermore, additive manufacturing processes can uniformly add rare earth elements to the alloy without significant delamination. Therefore, there is an urgent need to provide a rare earth-containing tungsten alloy filament and its preparation method. This method utilizes high-preheating additive manufacturing to effectively and uniformly add rare earth elements and reduce alloy grain size, addressing the issues of low strength and poor ductility in existing tungsten alloy filaments, thus meeting the requirements for their widespread application in solar silicon wafer cutting. Summary of the Invention

[0004] The purpose of this invention is to provide a tungsten alloy wire containing rare earth elements, its preparation method, and its application to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] The first aspect of the present invention provides a tungsten alloy wire containing rare earth elements, the tungsten alloy wire comprising the following elemental composition by mass fraction: yttrium (Y) 0-5 wt%, cerium (Ce) 0-5 wt%, and the balance being tungsten (W) and unavoidable impurities; the diameter of the tungsten alloy wire is 25-100 μm.

[0007] Preferably, by mass percentage, it comprises the following elemental composition: 4 wt% yttrium (Y), 1 wt% cerium (Ce), and the balance being tungsten (W) and unavoidable impurities.

[0008] Preferably, by mass percentage, it comprises the following elemental composition: 3 wt% yttrium (Y), 2 wt% cerium (Ce), and the balance being tungsten (W) and unavoidable impurities.

[0009] Preferably, by mass percentage, it comprises the following elemental composition: 2.5 wt% yttrium (Y), 2.5 wt% cerium (Ce), and the balance being tungsten (W) and unavoidable impurities.

[0010] Preferably, by mass percentage, it comprises the following elemental composition: 4.5 wt% yttrium (Y), 0.5 wt% cerium (Ce), and the balance being tungsten (W) and unavoidable impurities.

[0011] A second objective of this invention is to provide a method for preparing the aforementioned tungsten alloy wire, comprising the following steps:

[0012] S1. Weigh the raw materials according to the formula, and obtain the raw materials by pre-alloying powder or mechanical mixing powder;

[0013] S2. The obtained mixed raw materials are additively manufactured to obtain tungsten alloy billets;

[0014] S3. The obtained tungsten alloy billet is subjected to multiple passes of rotary forging and drawing to obtain tungsten alloy wire.

[0015] Preferably, the raw material in S1 is a pre-alloyed or pure metal powder with an average particle size in the range of 5 to 300 μm.

[0016] Preferably, the additive manufacturing described in S2 is a high-preheating additive manufacturing process based on a powder bed and synchronous powder feeding, specifically selected from selective laser melting, direct energy deposition, or electron beam selective melting, and the substrate is preheated to a temperature of over 1200°C and held at that temperature for 5 to 15 minutes.

[0017] Preferably, the rotary forging process described in S3 is carried out at 1000–1600°C, and each rotary forging is followed by treatment under liquid nitrogen.

[0018] A third objective of this invention is to provide the application of the aforementioned tungsten alloy wire in cutting processes.

[0019] The present invention has the following beneficial effects:

[0020] In this invention, the high preheating additive manufacturing process is utilized to improve the formability of high-melting-point refractory elements, thereby enabling high-precision control of tungsten alloy composition, significantly improving the quality of tungsten alloys, and thus enhancing wire production efficiency and product quality.

[0021] The greatest advantage of the method for preparing tungsten alloy wire containing rare earth elements proposed in this invention is that it reduces the extremely high requirements of raw material purity and particle size in traditional powder metallurgy processes. At the same time, by uniformly adding rare earth elements to refine the grains, the performance of tungsten alloy wire is significantly improved. The tungsten alloy wire containing rare earth elements prepared by the method proposed in this invention has higher strength and toughness.

[0022] The preparation method proposed in this invention is simple and inexpensive, suitable for industrial production, and is expected to further reduce the price of high-performance tungsten alloy wire, thus enabling its widespread application in the field of solar silicon wafer cutting. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings involved in the embodiments are now briefly described. Obviously, the drawings in the following description are merely illustrative of some embodiments of the present invention. For those skilled in the art, other forms of drawings can be constructed based on these drawings without creative effort.

[0024] Figure 1 This is a scanning electron microscope image of the tungsten alloy rod containing rare earth elements prepared in Example 1 of the present invention;

[0025] Figure 2 This is a scanning electron microscope image of the tungsten alloy rod containing rare earth elements prepared in Example 2 of the present invention;

[0026] Figure 3 This is a scanning electron microscope image of the tungsten alloy rod containing rare earth elements prepared in Example 3 of the present invention;

[0027] Figure 4 This is a scanning electron microscope image of the tungsten alloy rod containing rare earth elements prepared in Example 4 of the present invention. Detailed Implementation

[0028] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of the invention. However, those skilled in the art will understand that the invention may be implemented in other embodiments without these specific details.

[0029] Example 1:

[0030] A tungsten alloy wire containing rare earth elements comprises the following elemental composition by mass fraction: Y 4 wt%, Ce 1 wt%, and the balance W (containing unavoidable impurities). The preparation method of this tungsten alloy wire includes the following steps:

[0031] S1. First, Y (irregular particles) and Ce (irregular particles) are purified by electric arc melting and the surface oxide scale is removed for later use. Then, Y, Ce and W (irregular blocks) are weighed according to the above component ratio and melted to obtain a pre-alloy. Then, the pre-alloy is powdered to obtain raw materials with an average particle size of 10μm.

[0032] S2. Tungsten alloy is prepared by selective laser melting process. Before laser printing, the substrate is preheated to 1200℃ and held for 15 minutes. Tungsten alloy block is obtained by wire cutting.

[0033] S3. Tungsten alloy blocks (ingots) are rotary forged from 1600℃ to 1300℃ to obtain tungsten alloy rods. After water cooling, they are placed in liquid nitrogen for 30 minutes, then annealed at 600℃ for 30 minutes and water cooled to room temperature. The annealed tungsten alloy rods are then drawn into wires to obtain tungsten alloy wires containing rare earth elements.

[0034] The tungsten alloy rod containing rare earth elements obtained in Example 1 was subjected to wire cutting sampling, rough grinding, fine grinding, polishing, ultrasonic cleaning with deionized water, and drying. The microstructure was then scanned using a scanning electron microscope. The results are shown in [Figure 1]. Figure 1 The tensile properties of the tungsten alloy wire containing rare earth elements obtained in Example 1 were determined using a universal testing machine. The results are shown in Table 1.

[0035] Depend on Figure 1 The results show that the tungsten alloy microstructure containing rare earth elements obtained in Example 1 contains a very small amount of rare earth oxides.

[0036] Example 2:

[0037] A tungsten alloy wire containing rare earth elements comprises the following elemental composition by mass fraction: Y 3 wt%, Ce 2 wt%, and the balance W (containing unavoidable impurities). The preparation method of this tungsten alloy wire includes the following steps:

[0038] S1. First, Y (irregular particles) and Ce (irregular particles) are purified by electric arc melting and the surface oxide scale is removed for later use. Then, Y, Ce and W (irregular blocks) are weighed according to the above component ratio and melted to obtain a pre-alloy. Then, the pre-alloy is powdered to obtain raw materials with an average particle size of 55μm.

[0039] S2. Tungsten alloy is prepared by direct energy deposition process. Before laser printing, the substrate is preheated to 1200℃ and held for 15 minutes. Tungsten alloy block is obtained by wire cutting.

[0040] S3. Tungsten alloy blocks (ingots) are rotary forged from 1500℃ to 1100℃ to obtain tungsten alloy rods. After water cooling, they are placed in liquid nitrogen for 30 minutes, then annealed at 650℃ for 30 minutes and water cooled to room temperature. The annealed tungsten alloy rods are then drawn into wires to obtain tungsten alloy wires containing rare earth elements.

[0041] The tungsten alloy rods containing rare earth elements obtained in Example 2 were subjected to wire cutting sampling, rough grinding, fine grinding, polishing, ultrasonic cleaning with deionized water, and drying. The microstructure was then scanned using a scanning electron microscope. The results are shown in [Figure 1]. Figure 2 The tensile properties of the tungsten alloy wire containing rare earth elements obtained in Example 2 were determined using a universal testing machine. The results are shown in Table 1.

[0042] Depend on Figure 2 The results show that the tungsten alloy structure containing rare earth elements obtained in Example 2 contains a small amount of rare earth oxides.

[0043] Example 3:

[0044] A tungsten alloy wire containing rare earth elements comprises the following elemental composition by mass fraction: Y 2.5 wt%, Ce 2.5 wt%, and the balance W (containing unavoidable impurities). The preparation method of this tungsten alloy wire includes the following steps:

[0045] S1. Weigh Y (270 mesh), Ce powder (270 mesh) and W powder (270 mesh) according to the above component ratio, and ball mill each powder in a ball mill to obtain a mixed powder;

[0046] S2. Tungsten alloy is prepared by electron beam forming process. Before laser printing, the substrate is preheated to 1300℃ and held for 5 minutes. Tungsten alloy block is obtained by wire cutting.

[0047] S3. Tungsten alloy blocks (ingots) are rotary forged from 1550℃ to 1000℃ to obtain tungsten alloy rods. After water cooling, they are placed in liquid nitrogen for 30 minutes, then annealed at 700℃ for 30 minutes and water cooled to room temperature. The annealed tungsten alloy rods are then drawn into wires to obtain tungsten alloy wires containing rare earth elements.

[0048] The tungsten alloy rods containing rare earth elements obtained in Example 3 were subjected to wire cutting sampling, rough grinding, fine grinding, polishing, ultrasonic cleaning with deionized water, and drying. The microstructure was then scanned using a scanning electron microscope. The results are shown in [Figure 1]. Figure 3 The tensile properties of the tungsten alloy wire containing rare earth elements obtained in Example 3 were determined using a universal testing machine. The results are shown in Table 1.

[0049] Depend on Figure 3 The results show that the tungsten alloy structure containing rare earth elements obtained in Example 3 contains a small amount of rare earth oxides.

[0050] Example 4:

[0051] A tungsten alloy wire containing rare earth elements comprises the following elemental composition by mass fraction: Y 4.5 wt%, Ce 0.5 wt%, and the balance W (containing unavoidable impurities). The preparation method of this tungsten alloy wire includes the following steps:

[0052] S1. Weigh Y (3000 mesh), Ce powder (3000 mesh) and W powder (48 mesh) according to the above component ratio, and ball mill each powder in a ball mill to obtain a mixed powder;

[0053] S2. Tungsten alloy is prepared by electron beam forming process. Before laser printing, the substrate is preheated to 1250℃ and held for 10 minutes. Tungsten alloy block is obtained by wire cutting.

[0054] S3. Tungsten alloy blocks (ingots) are rotary forged from 1500℃ to 1200℃ to obtain tungsten alloy rods. After water cooling, they are placed in liquid nitrogen for 30 minutes, then annealed at 650℃ for 30 minutes and water cooled to room temperature. The annealed tungsten alloy rods are then drawn into wires to obtain tungsten alloy wires containing rare earth elements.

[0055] The tungsten alloy rods containing rare earth elements obtained in Example 4 were subjected to wire cutting sampling, rough grinding, fine grinding, polishing, ultrasonic cleaning with deionized water, and drying. The microstructure was then scanned using a scanning electron microscope. The results are shown in [Figure 4]. Figure 4 The tensile properties of the tungsten alloy wire containing rare earth elements obtained in Example 4 were determined using a universal testing machine. The results are shown in Table 1.

[0056] Depend on Figure 4 The results show that the tungsten alloy structure containing rare earth elements obtained in Example 4 contains some rare earth oxides.

[0057] Table 1. Tensile property test results of tungsten alloy wires containing rare earth elements in Examples 1-4.

[0058] Example Wire diameter / μm Tensile strength / MPa Wire diameter / μm Tensile strength / MPa Example 1 40 5400±200 60 4800±200 Example 2 40 5200±250 60 4650±150 Example 3 40 5250±250 60 4650±250 Example 4 40 5200±300 60 4400±200

[0059] The tungsten alloy wires prepared in Examples 1-4 of this invention have high tensile strength and are high-performance wires with a very broad application prospect in superhard material cutting engineering.

[0060] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A method for preparing tungsten alloy wire containing rare earth elements, characterized in that, The tungsten alloy wire comprises the following elemental composition by mass fraction: 2.5~5.0 wt% yttrium, 0.5~5.0 wt% cerium, and the balance being tungsten and unavoidable impurities; the diameter of the tungsten alloy wire is 25-100 μm. The method includes the following steps: S1. Weigh the raw materials according to the formula, and obtain the raw materials by pre-alloying powder or mechanical mixing powder; S2. The obtained raw materials are subjected to additive manufacturing to obtain tungsten alloy billets; the additive manufacturing specifically includes the following: The high-preheating additive manufacturing process based on powder bed and synchronous powder feeding is specifically selected from selective laser melting, direct energy deposition or electron beam selective melting, and the substrate is preheated to a temperature of 1200 ℃ or higher and held for 5~15 min. S3. The obtained tungsten alloy billet is subjected to multiple passes of rotary forging and drawing to obtain tungsten alloy wire.

2. The method for preparing tungsten alloy wire containing rare earth elements according to claim 1, characterized in that, The elemental composition includes the following mass fractions: 4 wt% yttrium, 1 wt% cerium, and the balance being tungsten and unavoidable impurities.

3. The method for preparing tungsten alloy wire containing rare earth elements according to claim 1, characterized in that, The elemental composition includes the following mass fractions: 3 wt% yttrium, 2 wt% cerium, and the balance being tungsten and unavoidable impurities.

4. The method for preparing tungsten alloy wire containing rare earth elements according to claim 1, characterized in that, The elemental composition comprises the following mass fractions: 2.5 wt% yttrium, 2.5 wt% cerium, and the balance being tungsten and unavoidable impurities.

5. The method for preparing tungsten alloy wire containing rare earth elements according to claim 1, characterized in that, Including the following mass fractions of elements Composition: 4.5 wt% yttrium, 0.5 wt% cerium and balance, the balance being tungsten and unavoidable impurities.

6. The method for preparing tungsten alloy wire containing rare earth elements according to claim 1, characterized in that, The raw material mentioned in S1 is an alloy powder made by ball milling pre-alloyed or pure metal powder with an average particle size in the range of 5 to 300 μm.

7. The method for preparing tungsten alloy wire containing rare earth elements according to claim 1, characterized in that, The rotary forging process described in S3 is carried out at 1000–1600 °C, and each rotary forging is followed by treatment under liquid nitrogen.

8. The application of tungsten alloy wire containing rare earth elements prepared by the method of any one of claims 1-7 in the cutting of solar silicon wafers.

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