Forming method of high-strength alloy micro gear

Abstract

The invention relates to a forming method of a high-strength alloy micro gear. The forming method comprises the following steps that S1, a high-strength alloy bar is put into an electrode induction gas atomization furnace; the high-strength alloy bar comprises the following components in percentage by weight: 10-20% of Cr; 8%-16% of Co; 5%-12% of Ni; 4%-8% of Mo; 3%-5% of W; 3%-5% of V; and the balance of Fe. S2, melting the high-strength alloy bar under electrode induction heating to form a liquid alloy; s3, the quantitative liquid alloy is intermittently sprayed out of a nozzle of the atomization furnace by controlling the descending speed of the atomization pressure, and a micro gear is formed in each time of spraying; the nozzle comprises a body, and a through forming inner cavity is formed in the body. The cross section of the forming inner cavity is the circumferential outer contour of the micro gear to be formed; and S4, the sprayed micro gear is cooled and screened, and the required high-strength alloy micro gear is obtained. Through the technological means of atomization forming of the high-strength alloy micro gear, the gear machining efficiency and quality are improved, and meanwhile the gear has the excellent mechanical property and physical property.

Description

Technical Field

[0001] The invention relates to the field of preparation of high-strength alloy micro gears, and in particular to a forming method of high-strength alloy micro gears. Background Art

[0002] High-strength alloy gears have the advantages of high strength, high toughness, corrosion resistance, easy processing and welding, and have shown broad application prospects in aerospace, medical equipment, automobile manufacturing and other fields. Compared with traditional steel gears, high-strength alloy gears have lighter weight and higher strength, which helps to reduce the mass of mechanical systems and improve the performance and efficiency of the system. In addition, high-strength alloy gears can work in higher temperatures and harsh environments and have excellent corrosion resistance.

[0003] As the consumer electronics industry has increasingly stringent requirements for the mechanical properties of metal materials, especially in the context of the high precision and complexity of the hinge transmission parts of current folding mobile phones, high strength, toughness, wear resistance and corrosion resistance are required for hinge transmission parts. Therefore, high-strength alloy micro gears have become the preferred material for this part. However, traditional processing technology makes it difficult to manufacture gears with a modulus ≤ 0.1, especially small modulus gears and micro gears.

[0004] High-strength alloy gears have significant advantages in high strength, toughness, corrosion resistance and easy processing and forming, and are widely used in aerospace, medical equipment and automobile manufacturing. Compared with traditional steel gears, their lighter weight and higher strength help improve the performance and efficiency of mechanical systems, and they can perform well in harsh environments. As the consumer electronics industry increases its requirements for high precision and complexity, high-strength alloy micro gears have shown unique advantages in the hinge transmission parts of folding mobile phones. However, the manufacture of micro gears with a modulus ≤0.1 still faces challenges from traditional processing techniques, and a technological breakthrough is urgently needed. Summary of the invention

[0005] The purpose of the present invention is to provide a method for forming a high-strength alloy micro gear, which improves the processing efficiency and quality of the high-strength alloy gear by atomizing the high-strength alloy micro gear, and has excellent mechanical and physical properties. It has outstanding advantages in the field of preparing high-strength micro gears.

[0006] The technical solution to achieve the purpose of the present invention is: the present invention comprises the following steps: S1. Put the high-strength alloy rod into the electrode induction gas atomization furnace; the high-strength alloy rod includes Cr: 10%-20%; Co: 8%-16%; Ni: 5%-12%; Mo: 4%-8%; W: 3%-5%; V: 3%-5%; the rest is Fe; S2, melting the high-strength alloy rod under electrode induction heating, heating it to a temperature exceeding its melting point, and forming a liquid alloy; S3, micro gear forming: first, by controlling the decreasing speed of the atomization pressure, a certain amount of liquid alloy is intermittently ejected from the nozzle of the electrode induction gas atomization furnace, and each ejection forms a micro gear; the micro gear is in a state of being shaped before it is exposed from the nozzle; the end face of the micro gear in the state of being shaped close to the nozzle pressure end is a flat end face, and the end face of the micro gear in the state of being shaped close to the nozzle outlet is the end face to be shaped, and the end face to be shaped is provided with a non-flat part to be removed; when the micro gear in the state of being shaped comes out from the discharge port of the nozzle, the air nozzle arranged at the discharge port of the nozzle blows and removes the non-flat part exposed from the discharge port of the nozzle; after the non-flat part is blown and removed, the micro gear in the state of being shaped becomes a micro gear with flat ends and is ejected from the nozzle; The nozzle comprises a body, and a through-shaped inner cavity is provided on the body; the cross section of the inner cavity is the circumferential outer contour of the micro gear to be formed; S4. Cool and screen the ejected micro gears to obtain the required high-strength alloy micro gears.

[0007] Furthermore, in the above step S2, the high-strength alloy rod is heated to a temperature of 1660-1760° C. to form a liquid alloy.

[0008] Furthermore, in the above step S3, the decreasing speed of the atomization pressure is 60-80 mm / min, and the pressure is 6-10 MPa; and the length of the forming inner cavity is 50 mm.

[0009] Furthermore, in the above step S3, the purge pressure of the air nozzle is 8-12 MPa.

[0010] Furthermore, in the above step S3, the ejected micro-gears are cooled at a cooling rate of 60000-85000 K / s.

[0011] Furthermore, the outer diameter of the forming inner cavity is 0.1 mm; the material of the nozzle is a material with high temperature resistance, corrosion resistance and high yield. The step S4 prepares a high-strength alloy micro gear with a tooth top circle diameter of 0.1 mm and a modulus of 0.01.

[0012] The present invention has positive effects: the micro gear prepared by the present invention has the following characteristics: (1) Complex shape preparation capability: The atomization forming method can prepare micro gears with complex geometric shapes, including internal and external gears, and the tooth shape and pitch can be adjusted according to the design requirements. This facilitates the realization of micro gears with micron-level precision and special shapes; (2) Dimensional accuracy and consistency: The atomization forming method can produce micro-gear products with high precision and consistency. By optimizing the heating and cooling control parameters, the consistency of particle size and shape can be achieved. This consistency makes the fit between micro-gears tighter and improves the overall performance; (3) High material utilization rate: Combined with the atomization process, high-strength alloy bars can be directly converted into precision gears, achieving efficient utilization of materials. Compared with traditional mechanical processing methods, atomization forming can reduce material waste and processing loss; (4) Flexibility in alloy composition control: The atomization forming method can flexibly adjust and control the composition and structure of high-strength alloy micro gears. By mixing alloy elements in different proportions, specific mechanical properties and wear resistance requirements can be achieved. In addition, the composition gradient control of different areas can be achieved during the forming process; (5) High production efficiency: The atomization forming method can realize mass production and improve production efficiency. Multiple gears can be prepared at the same time in one forming process, which effectively reduces processing time and cost. In addition, atomization forming can also realize automated and continuous production, further improving production efficiency; (6) Optimize the atomization process, increase the descending pressure and descending speed, and increase the speed of the metal liquid flow to improve the efficiency of the entire production process and increase the output, and also reduce the formation of inclusions and impurities, and improve the purity of the product. At the same time, the cooling rate is increased to avoid excessive oxidation and other high-temperature reactions; (7) Nickel, as a toughening agent, can significantly improve the toughness and fracture resistance of gears. Especially in low temperature environments, nickel can effectively slow down the growth rate of grains and refine the grain structure, thereby improving the mechanical properties and fatigue resistance of the material. In addition, nickel can also improve the corrosion resistance of gears and extend their service life.

[0013] The main role of chromium in high-strength gears is to enhance hardness and wear resistance. Chromium can form stable carbides with carbon, such as Cr23C6. The dispersion and precipitation of these carbides further enhance the surface hardness and wear resistance of the gears. In addition, chromium can also form a dense chromium oxide protective film to improve the stability of gears in high temperature and corrosive environments.

[0014] Cobalt is mainly used to improve the thermal stability and oxidation resistance of gears in high temperature environments. Cobalt can inhibit the coarsening of carbides and maintain the stability of the gear microstructure, thereby improving its long-term working ability under high temperature and high load. In addition, the addition of cobalt also helps to improve the mechanical properties and fatigue resistance of gears.

[0015] Molybdenum plays a reinforcing role in high-strength gears and can effectively improve the strength and toughness of gears. Molybdenum can form high-strength solid solutions and carbides, improving the load-bearing capacity and wear resistance of gears under dynamic loads. In addition, molybdenum can also improve the high-temperature stability of gears and extend their service life. In summary, the atomization forming method of high-strength alloy micro gears has the advantages of shape complexity, dimensional accuracy, high material utilization, flexible alloy composition control, excellent mechanical properties, physical properties and high production efficiency. It is suitable for the rapid, efficient and high-quality preparation of micro gears. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments and in conjunction with the accompanying drawings, wherein Figure 1 is a schematic diagram of the electrode induction gas atomization furnace of the present invention; Figure 2 It is a schematic diagram of the structure of the nozzle in the present invention; Figure 3 Schematic diagram of the high-strength alloy micro gear in the present invention.

[0017] In the figure, there are an electrode induction gas atomization furnace 1, a nozzle 2, a forming cavity 21, and a cooling tank 3. DETAILED DESCRIPTION

[0018] (Example 1) S1. Place the high-strength alloy rod into the electrode induction gas atomization furnace 1 (such as Figure 1 ); The high-strength alloy rods include Cr: 20wt%; Co: 16wt%; Ni: 12wt%; Mo: 8wt%; W: 5wt%; V: 5wt%; the rest is Fe; S2, heating the high-strength alloy rod to 1700°C above its melting point to form a liquid alloy; S3, micro-gear forming: first, by controlling the decreasing speed of the atomization pressure, a certain amount of liquid alloy is intermittently ejected from the nozzle of the electrode induction gas atomization furnace 1, and each ejection forms a micro-gear; the micro-gear is in a state of being shaped before it is exposed from the nozzle 2; the end face of the micro-gear in the state of being shaped close to the nozzle pressure end is a flat end face, and the end face of the micro-gear in the state of being shaped close to the nozzle outlet is the end face to be shaped, and the end face to be shaped is provided with a non-flat part to be removed; when the micro-gear in the state of being shaped comes out from the discharge port of the nozzle 2, the air nozzle arranged at the discharge port of the nozzle 2 blows and removes the non-flat part exposed from the discharge port of the nozzle 2; after the non-flat part is blown and removed, the micro-gear in the state of being shaped becomes a micro-gear with flat ends and is ejected from the nozzle; The nozzle 2 includes a body, and a through-shaped inner cavity 21 is provided on the body; the cross section of the inner cavity 21 is the circumferential outer contour of the micro gear to be formed; the outer diameter of the inner cavity 21 is 0.1 mm; the structure of the nozzle 2 can be seen Figure 2 ; The material of the nozzle 2 has high temperature resistance, corrosion resistance and friction resistance; Among them, the atomization descending speed is controlled to be 80mm / min, the pressure is 10MPa; the length of the forming inner cavity is 50mm; at the same time, the air nozzle is controlled to be flat, and the pressure is 12MPa; to ensure that each sprayed particle is a micro gear (such as Figure 3 ); S4. The ejected micro-gear is promptly cooled in a cooling tank 3 at a cooling rate of 85000K / s. After cooling, a high-strength alloy micro-gear with a tooth top circle diameter of 0.1 mm and a module of 0.01 is obtained by screening.

[0019] (Example 2) Place the high-strength alloy rod into the electrode induction gas atomization furnace 1 (such as Figure 1 ); the high-strength alloy rod includes Cr: 10wt%; Co: 8wt%; Ni: 5wt%; Mo: 4wt%; W: 3wt%; V: 3wt%; the rest is Fe; the rest is the same as Example 1.

[0020] (Example 3) Place the high-strength alloy rod into the electrode induction gas atomization furnace 1 (such as Figure 1 ); the high-strength alloy rod includes Cr: 20wt%; Co: 16wt%; Ni: 12wt%; Mo: 8wt%; W: 5wt%; V: 5wt%; the rest is Fe; the atomization descent speed is 60mm / min; the pressure is 6MPa; the purge pressure is 8MPa; the cooling rate is 60000K / s, and the others are the same as Example 1.

[0021] (Example 4) Place the high-strength alloy rod into the electrode induction gas atomization furnace 1 (such as Figure 1 ); the high-strength alloy rod includes Cr: 10wt%; Co: 8wt%; Ni: 5wt%; Mo: 4wt%; W: 3wt%; V: 3wt%; the rest is Fe; the atomization descent speed is 60mm / min; the pressure is 6MPa; the purge pressure is 8MPa; the cooling rate is 60000K / s, and the others are the same as Example 1.

[0022] (Example 5) Place the high-strength alloy rod into the electrode induction gas atomization furnace 1 (such as Figure 1); the high-strength alloy rod includes Cr: 15wt%; Co: 12wt%; Ni: 8wt%; Mo: 6wt%; W: 5wt%; V: 4wt%; the rest is Fe; the atomization descent speed is 70mm / min; the pressure is 8MPa; the purge pressure is 10MPa; the cooling rate is 70000K / s, and the others are the same as Example 1.

[0023] The components and preparation process parameters of Examples 1 to 5 are summarized as follows:

[0024] The performance tests of Examples 1 to 5 are as follows:

[0025] The comprehensive verification results show that the high-strength alloy gear of Example 1 has the highest yield strength of 1620 MPa. This shows that alloys with high Cr, Co, Ni, Mo, W, and V content can significantly improve the yield strength of micro gears. At the same time, the alloy has excellent wear resistance and surface hardness, and is suitable for micro gear applications in high load and high wear environments.

[0026] Although Examples 3, 4, and 5 are similar to Example 1 in alloy composition, their yield strength and hardness are slightly lower than those of Example 1 due to the different atomization descent speed, pressure, and cooling rate. This shows that appropriate process parameters are crucial to maintaining excellent mechanical properties of the alloy.

[0027] In summary, the high-strength alloy combination shown in Example 1 performs well in terms of yield strength and hardness, and is suitable for the manufacture of micro gears requiring high strength and wear resistance. Further research can optimize the process parameters to further improve the performance and stability of the alloy and promote its widespread application in practical industrial applications.

Claims

1. A method for forming a high-strength alloy micro gear; characterized in that The following steps are involved: S1. Place the high-strength alloy rod into an electrode induction gas atomization furnace; the high-strength alloy rod includes Cr: 10%-20% by weight; Co: 8%-16%; Ni: 5%-12%; Mo: 4%-8%; W: 3%-5%; V: 3%-5%; the rest is Fe; S2, melting the high-strength alloy rod under electrode induction heating, heating it to a temperature exceeding its melting point, and forming a liquid alloy; S3, micro gear forming: first, by controlling the decreasing speed of the atomization pressure, a certain amount of liquid alloy is intermittently ejected from the nozzle of the electrode induction gas atomization furnace, and each ejection forms a micro gear; the micro gear is in a state of being shaped before it is exposed from the nozzle; the end face of the micro gear in the state of being shaped close to the nozzle pressure end is a flat end face, and the end face of the micro gear in the state of being shaped close to the nozzle outlet is the end face to be shaped, and the end face to be shaped is provided with a non-flat part to be removed; when the micro gear in the state of being shaped comes out from the discharge port of the nozzle, the air nozzle arranged at the discharge port of the nozzle blows and removes the non-flat part exposed from the discharge port of the nozzle; after the non-flat part is blown and removed, the micro gear in the state of being shaped becomes a micro gear with flat ends and is ejected from the nozzle; The nozzle comprises a body, and a through-shaped inner cavity is provided on the body; the cross section of the inner cavity is the circumferential outer contour of the micro gear to be formed; S4. Cool and screen the ejected micro gears to obtain the required high-strength alloy micro gears.

2. The forming method of a high-strength alloy micro gear according to claim 1, characterized in that: In the step S2, the high-strength alloy rod is heated to a temperature of 1660-1760° C. to form a liquid alloy.

3. The forming method of a high-strength alloy micro gear according to claim 1, characterized in that: In step S3, the decreasing speed of the atomization pressure is 60-80 mm / min, and the pressure is 6-10 MPa; and the length of the forming inner cavity is 50 mm.

4. A method for forming a high-strength alloy micro gear according to claim 1 or 3, characterized in that: In the step S4, the ejected micro-gear is cooled at a cooling rate of 60000-85000 K / s.

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