High-temperature alloy capillary tube and preparation method and application thereof

Abstract

The high-temperature alloy capillary tube comprises the following chemical components in percentage by mass: 20.00 to 23.00 percent of Cr, 8.00 to 10.00 percent of Mo, 3.15 to 4.15 percent of Nb + Ta, less than or equal to 5.00 percent of Fe, less than or equal to 0.025 percent of C, less than or equal to 0.10 percent of Mn, less than or equal to 0.10 percent of Si, less than or equal to 0.0035 percent of S, less than or equal to 0.0035 percent of P, less than or equal to 0.10 percent of Co, less than or equal to 0.40 percent of Al, less than or equal to 0.30 percent of Ti, less than or equal to 20ppm of O, less than or equal to 30ppm of N, less than or equal to 5ppm of H and the balance of Ni and inevitable impurities. The outer diameter of the high-temperature alloy capillary tube is 0.5-2 mm; the wall thickness of the high-temperature alloy capillary tube ranges from 0.05 mm to 0.1 mm. The material components of the superfine regular high-temperature alloy capillary tube are optimized, so that the purity, the corrosion resistance, the size precision and the mechanical property of the high-temperature alloy capillary tube with the size can meet the strict requirements on the capillary tube in ultra-pure fluid transmission of an aerospace engine fuel control system or semiconductor equipment.

Description

Technical Field

[0001] This invention relates to the field of metal material processing technology, and in particular to a high-temperature alloy capillary, its preparation method, and its application. Background Technology

[0002] High-temperature alloy GH3625 has excellent corrosion resistance, high strength and good thermal stability, and is widely used in aerospace, petrochemical, marine engineering and other fields.

[0003] CN119351826A discloses a GH3625 high-temperature alloy pipe and its manufacturing process. The GH3625 high-temperature alloy pipe has the following composition by mass percentage: Mo: 8~10%, Nb: 3.25~4.00%, C: 0.003~0.065%, Cr: 20~23%, Fe≤5%, Cu≤0.30%, Al: 0.10~0.25%, Ti: 0.15~0.35%, Co≤1.0%, Si≤0.45%, Mn≤0.45%, S≤0.010%, P≤0.015%, B≤0.006%, Mg≤0.10%, W≤0.10%, with the remainder being Ni and unavoidable... Impurities; The production process includes the following steps performed in sequence: S1, ingot smelting, where the alloy material is smelted into an ingot through vacuum induction melting, vacuum casting electrode, and vacuum electroslag remelting technology; S2, ingot forging, where the ingot is heated to 1170℃~1190℃ for forging, with a final forging temperature of 950℃, and forged into cylindrical bars with a forging ratio of 4~10; S3, bar solution treatment, where the cylindrical bars are returned to the furnace and heated to 1130℃~1150℃, using water as a cooling medium for rapid cooling; the furnace temperature when the bars enter the furnace is 900℃, the holding time is 2.0min~5.0min / mm, and the temperature is increased to the target temperature at a rate of 150℃~250℃ / h; S4, first S4. Secondary billet processing: Drill the inner hole and turn the outer diameter of the bar stock, and flatten both ends to obtain the billet. A flared opening angle of α is machined at the inner diameter of the billet head. S5. Non-destructive testing of the billet: Perform ultrasonic testing on the billet obtained in S4. S6. First reaming: Use a vertical reamer to ream the heated billet to complete the first reaming. S7. Secondary billet processing: Turn the outer diameter and polish the billet after the first reaming, flatten both ends, machine a flared opening angle of α' at the inner diameter of the billet head, and machine a chamfer angle of β at the outer diameter of the tail. A fillet is machined at the connection between the chamfer and the billet body. S8. Secondary reaming: Use a vertical reamer to ream the heated billet to complete the second reaming. S9. Raw tube extrusion: Extrude the billet from the second reaming step in S8. After the blank is heated, it is extruded into a rough tube using a horizontal extrusion press; S10, the rough tube undergoes solution treatment, which involves heating it to the required temperature in stages using a chamber furnace and then water cooling; S11, cold rolling is performed using a Pilger cold rolling mill for two to seven passes, with a deformation of 30% to 60% per pass, a feed rate of 2.6 to 5.6 mm / pass, and a rolling speed of 30 to 60 passes / minute, while controlling the deformation of the last pass to 30% to 50%; after each pass of cold rolling, the intermediate tube is first degreased in a degreasing tank to remove the cold rolling oil, then undergoes solution treatment, and is then transferred to a mixed acid pickling tank for pickling to remove oxide scale; the solution treatment process for the intermediate tube in the cold rolling stage is heating at 1150℃ for 3.0 to 6 minutes.0 min / mm, rapid cooling is achieved using water as the cooling medium; S12, solution treatment of finished tubes: cold-rolled tubes with an inner diameter of 35mm and above are heated to a certain temperature and then water-cooled. The process is: heating at 960℃~1030℃ for 3.0min~8.0min / mm, with rapid cooling achieved using water as the cooling medium within 60 seconds; cold-rolled tubes with an inner diameter of less than 35mm and a wall thickness of less than 5mm are heat-treated in a protective atmosphere bright annealing furnace. The process is: heating at 960℃~1030℃ for 3.0min~8.0min / mm, with strong convection jet of protective gas + water cooling jacket; S13, finishing treatment: straightening, inspection, surface treatment, end flattening, and packaging. Its room temperature mechanical properties include a maximum tensile strength of 883MPa, a maximum yield strength of 389MPa, and a maximum grain size of 5.5.

[0004] Therefore, it is of great significance to develop a high-temperature alloy capillary that simultaneously ensures purity, dimensional accuracy, and mechanical properties. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a high-temperature alloy capillary, its preparation method, and its application. This invention optimizes the material composition of ultra-fine, regular high-temperature alloy capillary, ensuring that the purity, corrosion resistance, dimensional accuracy, and mechanical properties of the high-temperature alloy capillary of this size meet the stringent requirements for capillary tubes in ultrapure fluid transmission in aerospace engine fuel control systems or semiconductor devices.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a high-temperature alloy capillary, the chemical composition of which, by mass percentage, comprises: Cr: 20.00~23.00%, Mo: 8.00~10.00%, Nb+Ta: 3.15~4.15%, Fe≤5.00%, C≤0.025%, Mn≤0.10%, Si≤0.10%, S≤0.0035%, P≤0.0035%, Co≤0.10%, Al≤0.40%, Ti≤0.30%, O≤20ppm, N≤30ppm and H≤5ppm, with the remainder being Ni and unavoidable impurities;

[0008] The outer diameter of the high-temperature alloy capillary is 0.5~2mm;

[0009] The wall thickness of the high-temperature alloy capillary is 0.05~0.1mm.

[0010] High-temperature alloy capillaries with an outer diameter of 0.5~2mm and a wall thickness of 0.05~0.1mm are products with extremely high manufacturing technical difficulty. This is because maintaining an outer diameter of 0.5~2mm along the entire length of the high-temperature alloy capillary is very difficult, requiring extremely precise molds and a stable manufacturing process. Furthermore, the minimum wall thickness of existing high-temperature alloy capillaries is 1.5mm, while the high-temperature alloy capillaries of this invention have a wall thickness of 0.05~0.1mm. This means that any tiny deviation will lead to eccentricity or uneven wall thickness. Simultaneously, any tiny surface scratches, pits, or inclusions may also cause… As stress concentration points, these capillaries can directly lead to leakage or breakage during subsequent processing or use. This invention optimizes the material composition of high-temperature alloy capillaries of this size by limiting the content of Mn, Si, S, P, Co, O, N, and H elements in capillaries with an outer diameter of 0.5~2mm and a wall thickness of 0.05~0.1mm, and further limiting the content of Nb+Ta. This ensures that the purity, corrosion resistance, dimensional accuracy, and mechanical properties of high-temperature alloy capillaries of this size meet the stringent requirements for capillaries in ultrapure fluid transmission in aerospace engine fuel control systems or semiconductor devices.

[0011] In this invention, the "high-temperature alloy" in the high-temperature alloy capillary refers to a nickel-based alloy material that can work for a long time under high temperature above 600℃ and under certain stress. It has excellent high-temperature strength, good oxidation and hot corrosion resistance, good fatigue performance, fracture toughness and other comprehensive properties.

[0012] The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: Cr: 20.00~23.00%, for example, it can be 20.00%, 20.50%, 21.00%, 21.50%, 22.00%, 22.50% or 23.00%, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0013] The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: Mo: 8.00~10.00%, for example, it can be 8.00%, 8.50%, 9.00%, 9.50% or 10.00%, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0014] The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: Nb+Ta: 3.15~4.15%, for example, 3.15%, 3.35%, 3.55%, 3.75%, 3.95% or 4.15%, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0015] The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: Fe≤5.00%, for example, it can be 1.00%, 2.00%, 3.00%, 4.00% or 5.00%, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0016] The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: C ≤ 0.025%, for example, 0.002%, 0.005%, 0.010%, 0.015%, 0.020% or 0.025%, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0017] The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: Mn≤0.10%, for example, it can be 0.01%, 0.02%, 0.04%, 0.06%, 0.08% or 0.10%, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0018] The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: Si ≤ 0.10%, for example, it can be 0.02%, 0.04%, 0.06%, 0.08% or 0.10%, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0019] The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: S≤0.0035%, for example, it can be 0.0010%, 0.0015%, 0.0020%, 0.0025%, 0.0030% or 0.0035%, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0020] The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: P≤0.0035%, for example, it can be 0.0015%, 0.0020%, 0.0025%, 0.0030% or 0.0035%, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0021] The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: Co ≤ 0.10%, for example, it can be 0.01%, 0.02%, 0.04%, 0.06%, 0.08% or 0.10%, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0022] The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: Al ≤ 0.40%, for example, it can be 0.20%, 0.25%, 0.30%, 0.35% or 0.40%, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0023] The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: Ti ≤ 0.30%, for example, it can be 0.10%, 0.15%, 0.20%, 0.25% or 0.30%, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0024] The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: 0 ≤ 20 ppm, for example, 5 ppm, 8 ppm, 12 ppm, 16 ppm or 20 ppm, but is not limited to the listed values. Other unlisted values ​​within the above range also apply.

[0025] The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: N≤30ppm, for example, 10ppm, 15ppm, 20ppm, 25ppm or 30ppm, but is not limited to the listed values. Other unlisted values ​​within the above range also apply.

[0026] The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: H ≤ 5ppm, for example, it can be 1ppm, 2ppm, 3ppm, 4ppm or 5ppm, but is not limited to the listed values. Other unlisted values ​​within the above range also apply.

[0027] The outer diameter of the high-temperature alloy capillary is 0.5~2mm, for example, it can be 0.5mm, 0.8mm, 1.2mm, 1.5mm or 2mm, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0028] The wall thickness of the high-temperature alloy capillary is 0.05~0.1mm, for example, it can be 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm or 0.1mm, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0029] As a preferred technical solution of the present invention, the wall thickness uniformity deviation of the high-temperature alloy capillary is -0.01~0.01mm, for example, it can be -0.01mm, -0.005mm, 0mm, 0.005mm or 0.01mm, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0030] Preferably, the inner surface roughness of the high-temperature alloy capillary is <0.8μm, for example, it can be 0.3μm, 0.4μm, 0.5μm, 0.6μm or 0.7μm, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0031] Preferably, the outer surface roughness of the high-temperature alloy capillary is <0.4μm, for example, it can be 0.1μm, 0.15μm, 0.2μm, 0.25μm, 0.3μm or 0.35μm, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0032] Preferably, the straightness of the high-temperature alloy capillary is ≤0.5mm / m, for example, it can be 0.1mm / m, 0.2mm / m, 0.3mm / m, 0.4mm / m or 0.5mm / m, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0033] Preferably, the room temperature mechanical properties of the high-temperature alloy capillary include a yield strength ≥ 500 MPa, such as 500 MPa, 510 MPa, 520 MPa, 530 MPa, 540 MPa or 550 MPa; a tensile strength ≥ 900 MPa, such as 900 MPa, 910 MPa, 920 MPa, 930 MPa, 940 MPa or 950 MPa; and an elongation ≥ 48%, such as 48%, 49%, 50%, 51% or 52%, but not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0034] The room temperature mechanical properties in this invention refer to the mechanical properties tested at 25~30℃.

[0035] Preferably, the grain size grade of the high-temperature alloy capillary is ≥7, for example, it can be grade 7, grade 8, grade 9 or grade 10, and the grain size difference of the high-temperature alloy capillary is ≤1, for example, it can be grade 0 or grade 1, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0036] In a second aspect, the present invention provides a method for preparing a high-temperature alloy capillary according to the first aspect, the method comprising the following steps:

[0037] (1) The raw materials are mixed according to the proportion of each element, and vacuum induction melting, electroslag remelting and forging are carried out in sequence to obtain a billet;

[0038] (2) Inclusion detection and ultrasonic testing are performed on the billet;

[0039] (3) The billet from step (2) is subjected to hot extrusion to obtain a rough tube;

[0040] (4) The rough tube is subjected to a first cold rolling process and a first annealing process in sequence to obtain annealed tube material;

[0041] (5) The annealed pipe is subjected to a second cold rolling process and a second annealing process in sequence to obtain a preliminary finished pipe;

[0042] (6) The preliminary finished pipe is subjected to finishing and heat treatment in sequence to obtain a high-temperature alloy capillary tube with an outer diameter of 0.5~2mm and a wall thickness of 0.05~0.1mm.

[0043] This invention involves mixing novel elemental materials to ensure the purity and accurate proportions of each element. The mixture is then subjected to vacuum induction melting, electroslag remelting, and forging to obtain a billet. Vacuum induction melting is performed in a vacuum environment to prevent oxidation of the added raw materials, ensuring the alloy composition meets target requirements. Simultaneously, vacuum induction melting removes most gases and impurities. The alloy ingot obtained from vacuum induction melting is then used as a consumable electrode for electroslag remelting in the presence of slag. Here, the slag adsorbs inclusions in the raw materials, further improving the purity of the final high-temperature alloy capillary. This process also yields a uniform and refined solidification structure, enhancing the chemical composition uniformity of the final high-temperature alloy capillary. Subsequently, forging is performed, where the alloy ingot is forged at high temperature to break up the as-cast structure, compact internal defects, improve the density and uniformity of the alloy ingot, and initially shape the ingot into a round billet. The billet is then subjected to inclusion detection and ultrasonic testing to ensure the final high-temperature alloy capillary is of high quality. To ensure the uniformity and reliability of the performance of high-temperature alloy capillary tubes, the billet is hot-extruded to ensure uniform wall thickness and surface quality. It then undergoes a first cold rolling and first annealing process, followed by a second cold rolling and second annealing. Cold rolling induces plastic deformation in the billet, precisely controlling the wall thickness and diameter-to-thickness ratio, and improving the tube's strength and hardness. Annealing after cold rolling eliminates internal stress, restores the tube's plasticity and toughness, and further enhances the consistency of the microstructure of the preliminary finished tube. Finally, the preliminary finished tube undergoes finishing and heat treatment to achieve optimal corrosion resistance and mechanical properties. Through the synergistic effect of the above processes, this invention prepares high-temperature alloy capillary tubes with an outer diameter of 0.5~2mm and a wall thickness of 0.05~0.1mm, achieving the preparation of ultra-fine, regular high-temperature alloy capillary tubes. The purity, corrosion resistance, dimensional accuracy, and mechanical properties of the prepared high-temperature alloy capillary tubes meet the stringent requirements for capillary tubes in ultrapure fluid transmission for aerospace engine fuel control systems or semiconductor equipment.

[0044] As a preferred technical solution of the present invention, the temperature of the vacuum induction melting process is 1500~1600℃, for example, it can be 1500℃, 1520℃, 1540℃, 1560℃, 1580℃ or 1600℃, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0045] Preferably, the vacuum degree of the vacuum induction melting process is ≤2.6Pa, for example, it can be 0.5Pa, 1.0Pa, 1.5Pa, 2.0Pa or 2.6Pa, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0046] Preferably, the vacuum induction melting process takes 20 to 50 minutes, for example, 20 minutes, 30 minutes, 40 minutes or 50 minutes, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0047] Preferably, the electromagnetic stirring time in the vacuum induction melting process is 10 to 30 minutes, for example, it can be 10 minutes, 15 minutes, 20 minutes, 25 minutes or 30 minutes, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0048] Preferably, the casting temperature in the vacuum induction melting process is 1480~1520℃, for example, it can be 1480℃, 1490℃, 1500℃, 1510℃ or 1520℃, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0049] Preferably, the electroslag remelting process includes: grinding the vacuum induction ingot obtained from the vacuum induction melting process to obtain an induction electrode, and then welding the induction electrode to an auxiliary electrode and loading it into an electroslag remelting furnace for electroslag remelting.

[0050] Preferably, the slag system used in the electroslag remelting process comprises CaF2, Al2O3, CaO, and MgO.

[0051] Preferably, the mass ratio of CaF2, Al2O3, CaO and MgO in the slag system is (12~14):(2~4):(2~4):1, for example, it can be 12:2:2:1, 12:4:4:1, 13:3:3:1, 14:2:2:1 or 14:4:4:1, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0052] Preferably, the electroslag remelting process is carried out under an inert atmosphere.

[0053] This invention involves electroslag remelting under an inert atmosphere to effectively control gas intake during the electroslag remelting process, thereby stabilizing the oxygen content of the final high-temperature alloy capillary to below 20 ppm and the hydrogen content to below 5 ppm.

[0054] Preferably, the melting rate of the electroslag remelting process is 3~5 kg / min, for example, it can be 3 kg / min, 3.5 kg / min, 4 kg / min, 4.5 kg / min or 5 kg / min, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0055] Preferably, the preparation method further includes machining the electroslag remelted ingot between the electroslag remelting treatment and the forging billet treatment to obtain a melt-cast ingot.

[0056] In this invention, the finishing process can remove the oxide scale and defects on the surface of the ingot after electroslag remelting, resulting in a high-purity cast ingot.

[0057] As a preferred technical solution of the present invention, the forging billet treatment includes: heating the electroslag remelted ingot to 1190~1210℃ in a heat treatment furnace, holding it at that temperature for ≥4h, and then forging it to obtain the billet. The heating temperature is 1190~1210℃, for example, it can be 1190℃, 1195℃, 1200℃, 1205℃ or 1210℃, and the holding time is ≥4h, for example, it can be 4h, 4.2h, 4.4h, 4.6h, 4.8h or 5h, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0058] Preferably, the initial forging temperature of the forging billet treatment is ≥1050℃, for example, it can be 1050℃, 1100℃, 1150℃, 1200℃ or 1250℃, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0059] Preferably, the final forging temperature of the forging billet treatment is ≥900℃, for example, it can be 900℃, 920℃, 940℃, 960℃, 980℃ or 1000℃, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0060] Preferably, the forging ratio of the forging blanking process is 3 to 5, for example, it can be 3, 3.5, 4, 4.5 or 5, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0061] The specific operations of the forging blanking process in this invention can be adjusted by those skilled in the art according to their needs, and are not limited here.

[0062] As a preferred technical solution of the present invention, the temperature of the hot extrusion treatment is 1150~1200℃, for example, it can be 1150℃, 1160℃, 1170℃, 1180℃, 1190℃ or 1200℃, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0063] Preferably, the extrusion ratio of the hot extrusion treatment is 5.5 to 7.09, for example, it can be 5.5, 5.8, 6.1, 6.5 or 7.09, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0064] Preferably, the extrusion speed of the hot extrusion process is ≤50mm / s, for example, it can be 30mm / s, 35mm / s, 40mm / s, 45mm / s or 50mm / s, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0065] The hot extrusion process in this invention has advantages over machining, drilling, and skew rolling, resulting in higher material utilization, better uniformity of raw tube wall thickness, and more complete microstructure.

[0066] Preferably, the outer diameter of the rough tube is 80~100mm, for example, it can be 80mm, 85mm, 90mm, 95mm or 100mm, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0067] Preferably, the wall thickness of the rough tube is 6 to 8 mm, for example, it can be 6 mm, 6.5 mm, 7 mm, 7.5 mm or 8 mm, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0068] As a preferred embodiment of the present invention, the thickness deformation rate of the first cold rolling process is greater than that of the second cold rolling process.

[0069] Preferably, the thickness deformation rate of the first cold rolling process is 10-40% greater than that of the second cold rolling process. For example, it can be 10%, 15%, 20%, 25%, 30%, 35%, or 40%, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0070] In this invention, the thickness deformation rate of the first cold rolling process is 10-40% greater than that of the second cold rolling process. That is, the second cold rolling process is more refined than the first cold rolling process. This invention ensures that the rough tube will not crack during the rolling process by first performing rough rolling and then fine rolling, and improves the dimensional accuracy and mechanical properties of the final high-temperature alloy capillary tube, so that it can meet the stringent requirements for capillary tubes in the ultrapure fluid transmission of aerospace engine fuel control systems or semiconductor equipment.

[0071] Preferably, the thickness deformation rate of the first cold rolling process is 40-50%, for example, it can be 40%, 42%, 44%, 46%, 48% or 50%, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0072] Preferably, the rolling speed of the first cold rolling process is 30~60 r / min, for example, it can be 30 r / min, 40 r / min, 50 r / min, 55 r / min or 60 r / min, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0073] Preferably, the feed rate of the first cold rolling process is 2 to 5 mm / time, for example, it can be 2 mm / time, 3 mm / time, 4 mm / time, 4.5 mm / time or 5 mm / time, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0074] In this invention, annealed tubes with high-precision dimensions, excellent surface quality, and superior mechanical properties are prepared through a combination of a first cold rolling process and a first annealing process. The advantage of this combined process is not simply the superposition of two processes, but rather that by sequentially performing the first cold rolling process and the first annealing process, effects that cannot be achieved by a single process are realized. The cold rolling process can precisely control the uniformity of the tube wall thickness, the tolerance of the outer diameter, and the roundness. However, the first cold rolling process introduces high residual stress, which makes the product dimensions unstable. The first annealing process can eliminate residual stress, improve the stability of the tube dimensions, and eliminate work hardening through recrystallization, restoring the plasticity and toughness of the tube. At the same time, this invention limits the parameters of the first cold rolling process to improve the mechanical properties, dimensional accuracy, straightness, and roughness of the finally prepared high-temperature alloy capillary tube, so that it can meet the stringent requirements for capillary tubes in the ultrapure fluid transmission of aerospace engine fuel control systems or semiconductor equipment.

[0075] Preferably, the number of repetitions of step (5) in the preparation method is 1 to 5 times, for example, it can be 1 time, 2 times, 3 times, 4 times or 5 times, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0076] Preferably, the thickness deformation rate of the second cold rolling process is 10-30%, for example, it can be 10%, 15%, 20%, 25% or 30%, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0077] Preferably, the rolling speed of the second cold rolling process is 20~40 r / min, for example, it can be 20 r / min, 25 r / min, 30 r / min, 35 r / min or 40 r / min, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0078] Preferably, the feed rate of the second cold rolling process is 1~3mm / time, for example, it can be 1mm / time, 1.5mm / time, 2mm / time, 2.5mm / time or 3mm / time, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0079] Similarly, in this invention, a combination process of multiple passes of second cold rolling and second annealing is performed to prepare a preliminary finished tube with high-precision dimensions, excellent surface quality and mechanical properties. At the same time, this invention limits the parameters of the second cold rolling process to further improve the mechanical properties, dimensional accuracy, straightness and roughness of the finally prepared high-temperature alloy capillary, so that it can meet the stringent requirements for capillary in ultrapure fluid transmission in aerospace engine fuel control systems or semiconductor equipment.

[0080] Preferably, the rolling oil temperature for the first cold rolling process and the second cold rolling process is independently 40~80℃, for example, it can be 40℃, 50℃, 60℃, 70℃ or 80℃, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0081] This invention avoids the formation of oxide scale at high temperatures by controlling the rolling oil temperature in the first and second cold rolling processes, thereby obtaining a bright and smooth surface.

[0082] Preferably, the temperatures of the first annealing treatment and the second annealing treatment are each independently 1080~1120℃, for example, 1080℃, 1090℃, 1100℃, 1110℃ or 1120℃, but are not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0083] Preferably, the time for the first annealing treatment and the second annealing treatment is independently 10 to 60 minutes, for example, 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes or 60 minutes, but not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0084] Preferably, after the second annealing treatment, the pipe is rapidly cooled with argon gas to 100~200°C to obtain the preliminary finished pipe.

[0085] As a preferred technical solution of the present invention, the finishing process includes straightening, tube cutting, cleaning and surface polishing processes performed in sequence.

[0086] Preferably, the straightening speed is 1~5m / min, for example, it can be 1m / min, 2m / min, 3m / min, 4m / min or 5m / min, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0087] Preferably, the straightness of the pre-finished pipe after the straightening treatment is ≤0.5mm / m, for example, it can be 0.1mm / m, 0.2mm / m, 0.3mm / m, 0.4mm / m or 0.5mm / m, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0088] Preferably, the cleaning agent used in the cleaning process includes any one or a combination of at least two of anhydrous ethanol, a weak alkaline degreasing agent, or a phosphoric acid solution, wherein typical but non-limiting combinations include: a combination of anhydrous ethanol and a weak alkaline degreasing agent, a combination of anhydrous ethanol and a phosphoric acid solution, a combination of a weak alkaline degreasing agent and a phosphoric acid solution, and a combination of anhydrous ethanol, a weak alkaline degreasing agent, and a phosphoric acid solution.

[0089] Preferably, the surface roughness of the pre-finished pipe after surface polishing is <0.4μm, for example, it can be 0.1μm, 0.15μm, 0.2μm, 0.25μm, 0.3μm or 0.35μm, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0090] Preferably, the inner surface roughness of the pre-finished pipe after surface polishing is <0.8μm, for example, it can be 0.3μm, 0.4μm, 0.5μm, 0.6μm or 0.7μm, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0091] Preferably, the heat treatment temperature is 960~1000℃, for example, it can be 960℃, 970℃, 980℃, 990℃ or 1000℃, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0092] Preferably, the heat treatment time is 10 to 30 minutes, for example, 10 minutes, 15 minutes, 20 minutes, 25 minutes or 30 minutes, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0093] In this invention, a calcining tube is used to support the preliminary finished pipe during the heat treatment process to prevent abnormal bending of the preliminary finished pipe.

[0094] Preferably, after the heat treatment, the material is rapidly cooled with argon gas to 50~100°C to obtain the high-temperature alloy capillary.

[0095] As a preferred technical solution of the present invention, the preparation method includes the following steps:

[0096] (1) The raw materials are mixed according to the proportion of each element, and vacuum induction melting, electroslag remelting and forging are carried out in sequence to obtain a billet;

[0097] (2) Inclusion detection and ultrasonic testing are performed on the billet;

[0098] (3) The billet from step (2) is subjected to hot extrusion treatment at a temperature of 1150~1200℃, an extrusion ratio of 5.5~7.09 and an extrusion speed of ≤50mm / s to obtain a rough tube with an outer diameter of 80~100mm and a wall thickness of 6~8mm.

[0099] (4) The rough tube is subjected to a first cold rolling process with a thickness deformation rate of 40-50%, a rolling speed of 30-60 r / min, and a feed amount of 2-5 mm / time, and a first annealing process with a temperature of 1080-1120℃ and a time of 10-60 min to obtain the annealed tube.

[0100] (5) The annealed pipe is subjected to a second cold rolling process with a thickness deformation rate of 10~30%, a rolling speed of 20~40 r / min, and a feed amount of 1~3 mm / time, and then subjected to a second annealing process with a temperature of 1080~1120℃ and a time of 10~60 min. The second cold rolling process and the second annealing process are repeated 1~5 times to obtain the preliminary finished pipe.

[0101] (6) The preliminary finished pipe is subjected to straightening, cutting, cleaning, surface polishing and heat treatment at a temperature of 960~1000℃ for 10~30min in sequence to obtain a high-temperature alloy capillary with an outer diameter of 0.5~2mm and a wall thickness of 0.05~0.1mm.

[0102] Thirdly, the present invention provides an application of the high-temperature alloy capillary according to the first aspect in the ultrapure fluid transport of aerospace engine fuel control systems and / or semiconductor devices.

[0103] The high-temperature alloy capillary of the present invention has high purity, corrosion resistance, dimensional accuracy and mechanical properties that can meet the stringent requirements for capillary in ultrapure fluid transport in aerospace engine fuel control systems and / or semiconductor devices.

[0104] Compared with the prior art, the present invention has at least the following beneficial effects:

[0105] (1) By optimizing the material composition of the tube, the present invention enables the high-temperature alloy capillary with an outer diameter of 0.5~2mm and a wall thickness of 0.05~0.1mm to meet the stringent requirements for capillary in ultrapure fluid transmission in aerospace engine fuel control systems or semiconductor equipment in terms of purity, corrosion resistance, mechanical properties and dimensional accuracy. Among them, the room temperature mechanical properties of the high-temperature alloy capillary are: yield strength ≥500MPa, tensile strength ≥900MPa, elongation ≥48%; the inner surface roughness of the high-temperature alloy capillary is <0.8μm, the outer surface roughness is <0.4μm, and the straightness of the high-temperature alloy capillary can be controlled below 0.5mm / m and the wall thickness uniformity deviation is less than ±0.01mm.

[0106] (2) This invention prepares high-temperature alloy capillary tubes with an outer diameter of 0.5~2mm and a wall thickness of 0.05~0.1mm by means of the synergistic effect of vacuum induction melting, electroslag remelting, forging, hot extrusion, first cold rolling, first annealing, second cold rolling, second annealing, finishing and heat treatment processes. This achieves the preparation of ultra-fine and regular high-temperature alloy capillary tubes, and ensures that the purity, corrosion resistance, dimensional accuracy and mechanical properties of the prepared high-temperature alloy capillary tubes can meet the stringent requirements for capillary tubes in ultrapure fluid transmission in aerospace engine fuel control systems or semiconductor equipment. Detailed Implementation

[0107] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0108] Example 1

[0109] This embodiment provides a high-temperature alloy capillary. The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: Cr: 21.39%, Mo: 8.65%, Nb+Ta: 3.57%, Fe: 2.91%, C: 0.0043%, Mn: 0.01%, Si: 0.08%, S: 0.0010%, P: 0.0029%, Co: 0.01%, Al: 0.22%, Ti: 0.14%, O: 10ppm, N: 15ppm, and H: 3ppm, with the remainder being Ni and unavoidable impurities, the total of which is 100%.

[0110] This embodiment also provides a method for preparing a high-temperature alloy capillary, the method comprising the following steps:

[0111] (1) The raw materials are mixed according to the proportion of each element, and vacuum induction melting, electroslag remelting and forging are carried out in sequence to obtain a billet;

[0112] The vacuum induction melting process involves a temperature of 1520℃, a vacuum degree of 2.0 Pa, and a time of 20 min. Simultaneously, electromagnetic stirring is performed for 10 min during the vacuum induction melting process, followed by casting at 1500℃ to obtain a vacuum induction ingot. The ingot is then ground to obtain an induction electrode with a diameter of 180 mm. This induction electrode is welded to an auxiliary electrode and placed in an electroslag remelting furnace. Under argon protection, electroslag remelting is performed at a melting rate of 4 kg / min. The resulting ingot is then machined to obtain a cast billet. This billet is then heated to 1200℃ in a heat treatment furnace and held for 5 hours before being forged to obtain a bar billet with a diameter of 80 mm. The initial forging temperature is 1150℃, the final forging temperature is 950℃, and the forging ratio is 4.

[0113] The slag used in electroslag remelting is CaF2, Al2O3, CaO and MgO in a mass ratio of 65:15:15:5;

[0114] (2) Inclusion detection and ultrasonic testing are performed on the billet;

[0115] (3) The billet from step (2) is subjected to hot extrusion treatment at a temperature of 1180℃, an extrusion ratio of 6.2 and an extrusion speed of 40mm / s to obtain a rough tube with an outer diameter of 89mm and a wall thickness of 7mm.

[0116] (4) The rough tube is subjected to a first cold rolling process with a thickness deformation rate of 45%, a rolling speed of 45 r / min, a feed rate of 3.5 mm / time, and a rolling oil temperature of 60°C, and then subjected to a first annealing process with a temperature of 1100°C and a time of 45 min to obtain the annealed tube.

[0117] (5) The annealed tube was subjected to a second cold rolling process using a multi-roll cyclic cold rolling mill with a thickness deformation rate of 20%, a rolling speed of 30 r / min, a feed rate of 2 mm / time, and a rolling oil temperature of 50°C. Then, a second annealing process was performed at a temperature of 1100°C for 45 min. The second cold rolling process and the second annealing process were repeated 5 times. The tube was then rapidly cooled to 150°C with argon gas to obtain a preliminary finished tube. The thickness deformation rate of the second cold rolling process during the cyclic process was 20%, 25%, 15%, 10%, and 10% respectively.

[0118] (6) The preliminary finished pipe is subjected to finishing treatment and heat treatment at 980°C for 25 minutes, and then rapidly cooled to 80°C with argon gas to obtain a high-temperature alloy capillary tube with an outer diameter of 1.5 mm and a wall thickness of 0.1 mm. The finishing treatment includes straightening treatment at a speed of 3 m / min to make the straightness of the preliminary finished pipe 0.3 mm / m, and then pipe cutting treatment. Then, it is cleaned with a 5 wt% weak alkali degreasing agent, and then surface polishing treatment is performed. During the heat treatment, a calcined tube is used to support the preliminary finished pipe.

[0119] Example 2

[0120] This embodiment provides a high-temperature alloy capillary. The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: Cr: 20.00%, Mo: 8.00%, Nb+Ta: 4.15%, Fe: 1.00%, C: 0.025%, Mn: 0.05%, Si: 0.02%, S: 0.0020%, P: 0.0015%, Co: 0.05%, Al: 0.30%, Ti: 0.30%, O: 20ppm, N: 10ppm, and H: 5ppm, with the remainder being Ni and unavoidable impurities, the total of which is 100%.

[0121] This embodiment also provides a method for preparing a high-temperature alloy capillary, the method comprising the following steps:

[0122] (1) The raw materials are mixed according to the proportion of each element, and vacuum induction melting, electroslag remelting and forging are carried out in sequence to obtain a billet;

[0123] The vacuum induction melting process involves a temperature of 1500℃, a vacuum degree of 0.5Pa, and a time of 50min. Simultaneously, electromagnetic stirring is performed for 30min during the vacuum induction melting process, followed by casting at 1520℃ to obtain a vacuum induction ingot. The ingot is then ground to obtain an induction electrode with a diameter of 200mm. This induction electrode is welded to an auxiliary electrode and placed in an electroslag remelting furnace. Under argon protection, electroslag remelting is performed at a melting rate of 3kg / min. The resulting ingot is then machined to obtain a cast billet. This billet is then heated to 1190℃ in a heat treatment furnace and held for 5.5h before being forged to obtain a bar billet with a diameter of 90mm. The initial forging temperature is 1050℃, the final forging temperature is 900℃, and the forging ratio is 5.

[0124] The slag used in electroslag remelting is CaF2, Al2O3, CaO and MgO in a mass ratio of 60:20:15:5;

[0125] (2) Inclusion detection and ultrasonic testing are performed on the billet;

[0126] (3) The billet from step (2) is subjected to hot extrusion treatment at a temperature of 1200℃, an extrusion ratio of 7.09 and an extrusion speed of 50mm / s to obtain a rough tube with an outer diameter of 80mm and a wall thickness of 8mm.

[0127] (4) The rough tube is subjected to a first cold rolling process with a thickness deformation rate of 40%, a rolling speed of 30 r / min, a feed amount of 2 mm / time, and a rolling oil temperature of 40°C, and then subjected to a first annealing process with a temperature of 1080°C and a time of 60 min to obtain the annealed tube.

[0128] (5) The annealed tube is subjected to a second cold rolling process with a thickness deformation rate of 10%, a rolling speed of 20 r / min, a feed rate of 1 mm / time, and a rolling oil temperature of 40°C using a multi-roll cyclic cold rolling mill. Then, a second annealing process is performed at a temperature of 1120°C for 20 min. The second cold rolling process and the second annealing process are repeated 3 times. The tube is then rapidly cooled to 100°C with argon gas to obtain a preliminary finished tube. The thickness deformation rate of the second cold rolling process during the cyclic process is 20%, 25%, and 30% respectively.

[0129] (6) The preliminary finished pipe is subjected to finishing treatment and heat treatment at 960°C for 30 minutes, and then rapidly cooled to 50°C with argon gas to obtain a high-temperature alloy capillary tube with an outer diameter of 2 mm and a wall thickness of 0.05 mm. The finishing treatment includes straightening treatment at a speed of 1 m / min to make the straightness of the preliminary finished pipe 0.5 mm / m, and then pipe cutting treatment. Then, it is cleaned with anhydrous ethanol and then surface polished. During the heat treatment, a calcined tube is used to support the preliminary finished pipe.

[0130] Example 3

[0131] This embodiment provides a high-temperature alloy capillary. The chemical composition of the high-temperature alloy capillary, by mass percentage, includes: Cr: 23.00%, Mo: 10.00%, Nb+Ta: 3.15%, Fe: 5.00%, C: 0.002%, Mn: 0.10%, Si: 0.10%, S: 0.0035%, P: 0.0035%, Co: 0.10%, Al: 0.40%, Ti: 0.10%, O: 5ppm, N: 30ppm, and H: 1ppm, with the remainder being Ni and unavoidable impurities, the total of which is 100%.

[0132] This embodiment also provides a method for preparing a high-temperature alloy capillary, the method comprising the following steps:

[0133] (1) The raw materials are mixed according to the proportion of each element, and vacuum induction melting, electroslag remelting and forging are carried out in sequence to obtain a billet;

[0134] The vacuum induction melting process involves a temperature of 1600℃, a vacuum degree of 2.6Pa, and a time of 20min. Simultaneously, electromagnetic stirring is performed for 15min during the vacuum induction melting process, followed by casting at 1480℃ to obtain a vacuum induction ingot. The ingot is then ground to obtain an induction electrode with a diameter of 160mm. This induction electrode is welded to an auxiliary electrode and placed in an electroslag remelting furnace. Under argon protection, electroslag remelting is performed at a melting rate of 5kg / min. The resulting ingot is then machined to obtain a cast billet. This billet is then heated to 1210℃ in a heat treatment furnace and held for 4 hours before being forged to obtain a bar billet with a diameter of 70mm. The initial forging temperature is 1250℃, the final forging temperature is 1000℃, and the forging ratio is 3.

[0135] The slag used in electroslag remelting is CaF2, Al2O3, CaO and MgO in a mass ratio of 70:10:15:5;

[0136] (2) Inclusion detection and ultrasonic testing are performed on the billet;

[0137] (3) The billet from step (2) is subjected to hot extrusion treatment at a temperature of 1150℃, an extrusion ratio of 5.5 and an extrusion speed of 30mm / s to obtain a rough tube with an outer diameter of 100mm and a wall thickness of 6mm.

[0138] (4) The rough tube is subjected to a first cold rolling process with a thickness deformation rate of 50%, a rolling speed of 60 r / min, a feed amount of 5 mm / time, and a rolling oil temperature of 80°C, and then subjected to a first annealing process with a temperature of 1120°C and a time of 10 min to obtain the annealed tube.

[0139] (5) The annealed tube is subjected to a second cold rolling process with a thickness deformation rate of 30%, a rolling speed of 40 r / min, a feed rate of 3 mm / time, and a rolling oil temperature of 80°C using a multi-roll periodic cold rolling mill. Then, a second annealing process is performed at a temperature of 1080°C for 60 min. The second cold rolling process and the second annealing process are repeated once. The tube is then rapidly cooled to 200°C with argon gas to obtain a preliminary finished tube. The thickness deformation rate of the second cold rolling process during the cyclic process is 25%.

[0140] (6) The preliminary finished pipe is subjected to finishing treatment and heat treatment at 1000℃ for 10min in sequence, and then rapidly cooled to 100℃ with argon gas to obtain a high-temperature alloy capillary with an outer diameter of 0.5mm and a wall thickness of 0.1mm. The finishing treatment includes straightening treatment at a speed of 5m / min to make the straightness of the preliminary finished pipe 0.1mm / m, and then pipe cutting treatment. Then, it is cleaned with a 10wt% phosphoric acid solution and then surface polishing treatment is performed. During the heat treatment, a calcined tube is used to support the preliminary finished pipe.

[0141] Example 4

[0142] This embodiment provides a high-temperature alloy capillary tube, which differs from Embodiment 1 only in that, except that the thickness deformation rate of the first cold rolling treatment in step (4) is 20%, the rest is the same as Embodiment 1.

[0143] Example 5

[0144] This embodiment provides a high-temperature alloy capillary tube, which differs from Embodiment 1 only in that, except that the thickness deformation rate of the first cold rolling treatment in step (4) is 80%, the rest is the same as Embodiment 1.

[0145] Example 6

[0146] This embodiment provides a high-temperature alloy capillary tube, which differs from Embodiment 1 only in that, except that the thickness deformation rate of the second cold rolling process in step (5) is 5%, the rest is the same as Embodiment 1.

[0147] Example 7

[0148] This embodiment provides a high-temperature alloy capillary tube, which differs from Embodiment 1 only in that, except that the thickness deformation rate of the second cold rolling treatment in step (5) is 50%, the rest is the same as Embodiment 1.

[0149] Example 8

[0150] This embodiment provides a high-temperature alloy capillary tube, which differs from Embodiment 1 only in that the number of cycles of the second cold rolling treatment and the second annealing treatment in step (5) is adjusted from 5 to 0. All other aspects are the same as in Embodiment 1.

[0151] Example 9

[0152] This embodiment provides a high-temperature alloy capillary tube, which differs from Embodiment 1 only in that the number of cycles of the second cold rolling treatment and the second annealing treatment in step (5) is adjusted from 5 to 10, and the thickness deformation rate of the second cold rolling treatment during the cycle treatment is 20%, 25%, 15%, 10%, 10%, 20%, 25%, 15%, 10% and 10% respectively. All other aspects are the same as in Embodiment 1.

[0153] Example 10

[0154] This embodiment provides a high-temperature alloy capillary tube, which differs from Embodiment 1 only in that the electroslag remelting treatment is not carried out under argon protection, while the rest is the same as Embodiment 1.

[0155] In this embodiment, the contents of O, N and H elements in the high-temperature alloy capillary are 35ppm, 42ppm and 8ppm, respectively.

[0156] Comparative Example 1

[0157] This comparative example provides a high-temperature alloy capillary tube, which differs from Example 1 only in that the preparation method does not include step (2), but is otherwise the same as Example 1.

[0158] Comparative Example 2

[0159] This comparative example provides a high-temperature alloy capillary tube, which differs from Example 1 only in that the hot extrusion process in step (3) is changed to skew rolling piercing process, and the piercing mill roll speed is 80 r / min, the feed rate is 3 mm / s, and the mandrel is a conical mandrel in the skew rolling piercing process. Otherwise, it is the same as Example 1.

[0160] Comparative Example 3

[0161] This comparative example provides a high-temperature alloy capillary tube, which differs from Example 1 only in that, except that step (4) only performs the first cold rolling process to obtain the cold-rolled tube, i.e., step (5) performs the second cold rolling process and the second annealing process on the cold-rolled tube to obtain the preliminary finished tube, the rest is the same as Example 1.

[0162] Comparative Example 4

[0163] This comparative example provides a high-temperature alloy capillary tube, which differs from Example 1 only in that, except for step (4), which involves only the first annealing treatment to obtain the annealed tube, the rest is the same as Example 1.

[0164] Comparative Example 5

[0165] This comparative example provides a high-temperature alloy capillary tube, which differs from Example 1 only in that, except for step (5) which involves only a second cold rolling process to obtain a preliminary finished tube, the rest is the same as Example 1.

[0166] Comparative Example 6

[0167] This comparative example provides a high-temperature alloy capillary tube, which differs from Example 1 only in that, except for step (5) which only involves a second annealing process to obtain a preliminary finished tube, the rest is the same as Example 1.

[0168] Comparative Example 7

[0169] This comparative example provides a high-temperature alloy capillary tube, which differs from Example 1 only in that step (6) is adjusted to perform heat treatment and finishing treatment on the preliminary finished tube in sequence, while the rest is the same as Example 1.

[0170] Inclusions in the billet obtained in step (1) were tested according to GB / T 10561-2005. The inclusion levels are shown in Table 1. Ultrasonic testing was performed on the billet obtained in step (1) according to GB / T4162 A. The test results are shown in Table 1. The outer diameter, wall thickness, grain size, inner surface roughness, outer surface roughness and straightness of the high-temperature alloy capillary were tested. The test results are shown in Table 2. Among them, the grain size and roughness were tested according to GB / T 6394-2017 and GB / T1031-2009 respectively. The formula for calculating the wall thickness uniformity deviation is: wall thickness deviation (mm) = maximum wall thickness - minimum wall thickness. The room temperature mechanical properties of the high-temperature alloy capillary were tested at 25~30℃ according to GB / T 228.1-2010. The corrosion resistance test of the high-temperature alloy capillary was performed according to ASTM G48-11A. The test results are shown in Table 3.

[0171] Table 1

[0172]

[0173] Table 2

[0174]

[0175] Table 3

[0176]

[0177] The test results show that:

[0178] (1) As can be seen from Examples 1 to 3, by optimizing the chemical composition and preparation process parameters of the high-temperature alloy capillary, the present invention can prepare a high-temperature alloy capillary with high dimensional accuracy, excellent mechanical properties and good corrosion resistance. Its yield strength is ≥520MPa, tensile strength is ≥925MPa, elongation is ≥49%, and corrosion rate is ≤0.03g / m 2 The inner surface roughness is <0.7μm, the outer surface roughness is <0.35μm, the straightness is ≤0.5mm / m, the wall thickness uniformity deviation is ≤0.008mm, and the grain size grade is ≥7.

[0179] (2) As can be seen from Examples 1 and 4-5, the thickness deformation rate of the first cold rolling treatment in Example 1 is 45%, which produces a high-temperature alloy capillary with a grain size of grade 8, and the yield strength of the high-temperature alloy capillary is 540 MPa, the tensile strength is 940 MPa, and the elongation is 50%; while the thickness deformation rate of the first cold rolling treatment in Example 4 is 20%, which produces a high-temperature alloy capillary with a grain size of grade 7, and the yield strength of the high-temperature alloy capillary is 510 MPa, the tensile strength is 920 MPa, and the elongation is 48%. In Example 5, the thickness deformation rate of the first cold rolling process is 80%, which produces a high-temperature alloy capillary with a grain size of grade 7. The high-temperature alloy capillary has a yield strength of 505 MPa, a tensile strength of 900 MPa, and an elongation of 48.5%. It can be seen that the present invention improves the mechanical properties and corrosion resistance of the final high-temperature alloy capillary by limiting the thickness deformation rate of the first cold rolling process, so that it can meet the stringent requirements for capillary in the ultrapure fluid transmission of aerospace engine fuel control systems or semiconductor equipment.

[0180] (3) As can be seen from Examples 1 and 6-7, the thickness deformation rates of the second cold rolling treatment in Example 1 are 20%, 20%, 25%, 15%, 10% and 10% respectively, which produces high-temperature alloy capillaries with a grain size of grade 8, and the yield strength of the high-temperature alloy capillaries is 540 MPa, the tensile strength is 940 MPa and the elongation is 50%; while the thickness deformation rates of the second cold rolling treatment in Example 6 are all 5%, which produces high-temperature alloy capillaries with a grain size of grade 6, and the yield strength of the high-temperature alloy capillaries is 485 MPa and the tensile strength is 890 MPa. a. The elongation is 47%. In Example 7, the thickness deformation rate of the second cold rolling process is 50%. The resulting high-temperature alloy capillary has a grain size of 6.5 and a yield strength of 495 MPa, a tensile strength of 895 MPa, and an elongation of 47.5%. It can be seen that the present invention improves the grain size, mechanical properties, and corrosion resistance of the final high-temperature alloy capillary by limiting the thickness deformation rate of the second cold rolling process, so that it can meet the stringent requirements for capillary in the ultrapure fluid transmission of aerospace engine fuel control systems or semiconductor equipment.

[0181] (4) As can be seen from Examples 1 and 8-9, in Example 1, the number of cycles for the second cold rolling and second annealing in step (5) is 5, and a high-temperature alloy capillary with a grain size of grade 8 is prepared. The yield strength of the high-temperature alloy capillary is 540 MPa, the tensile strength is 940 MPa, and the elongation is 50%. In Example 8, the number of cycles for the second cold rolling and second annealing in step (5) is 0, and a high-temperature alloy capillary with a grain size of grade 5 is prepared. The yield strength of the high-temperature alloy capillary is 470 MPa, the tensile strength is 880 MPa, and the elongation is 46%. In Example 9, the number of cycles for the second cold rolling and second annealing in step (5) is 0. The second annealing process involves 10 cycles, resulting in a high-temperature alloy capillary with a grain size of 8.5. The capillary exhibits a yield strength of 545 MPa, a tensile strength of 945 MPa, and an elongation of 50.5%. This demonstrates that by limiting the number of cycles in the second cold rolling and annealing processes, the present invention improves the grain size, mechanical properties, and corrosion resistance of the final high-temperature alloy capillary. This allows it to meet the stringent requirements for capillary tubes in ultrapure fluid transport applications in aerospace engine fuel control systems or semiconductor devices. Conversely, excessive cycles, while leading to a slight performance improvement, have limited impact and increase production costs.

[0182] (5) As can be seen from Examples 1 and 10, electroslag remelting treatment under an inert atmosphere can effectively reduce the content of O, N and H elements in the high-temperature alloy capillary, improve its purity and comprehensive performance. When it is not carried out under an inert atmosphere, the gas content increases and the corrosion resistance decreases.

[0183] (6) As can be seen from Example 1 and Comparative Example 1, inclusion detection and ultrasonic testing of the billet can effectively remove the defective billet and improve the performance of the final product. Without this step, the various properties of the high-temperature alloy capillary tube are significantly reduced.

[0184] (7) As can be seen from Example 1 and Comparative Example 2, compared with skew rolling piercing treatment, hot extrusion treatment can obtain high-temperature alloy capillary tubes with better wall thickness uniformity, surface quality and mechanical properties.

[0185] (8) As can be seen from Example 1 and Comparative Examples 3-6, the combination process of the first cold rolling treatment and the first annealing treatment, and the combination process of the second cold rolling treatment and the second annealing treatment are crucial to improving the performance of high-temperature alloy capillary tubes. When only a single cold rolling or annealing treatment is performed, the product performance will be significantly reduced.

[0186] (9) As can be seen from Example 1 and Comparative Example 7, the order of finishing and heat treatment has a certain impact on the performance of high-temperature alloy capillary tubes. Finishing before heat treatment can achieve better dimensional accuracy and surface quality.

[0187] In summary, this invention optimizes the material composition of the tube and, through the synergistic effect of vacuum induction melting, electroslag remelting, forging, hot extrusion, first cold rolling, first annealing, second cold rolling, second annealing, finishing, and heat treatment processes, ensures that the purity, corrosion resistance, dimensional accuracy, and mechanical properties of the prepared high-temperature alloy capillary meet the stringent requirements for capillary tubes in ultrapure fluid transmission for aerospace engine fuel control systems or semiconductor equipment.

[0188] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A high-temperature alloy capillary tube, characterized in that, The chemical composition of the high-temperature alloy capillary is expressed as a percentage by mass. Includes: Cr: 20.00~23.00%, Mo: 8.00~10.00%, Nb+Ta: 3.15~4.15%, Fe≤5.00%, C≤0.025%, Mn≤0.10%, Si≤0.10%, S≤0.0035%, P≤0.0035%, Co≤0.10%, Al≤0.40%, Ti≤0.30%, O≤20ppm, N≤30ppm and H≤5ppm, with the remainder being Ni and unavoidable impurities; The outer diameter of the high-temperature alloy capillary is 0.5~2mm; The wall thickness of the high-temperature alloy capillary is 0.05~0.1mm.

2. The high-temperature alloy capillary tube according to claim 1, characterized in that, The wall thickness uniformity deviation of the high-temperature alloy capillary is -0.01~0.01mm; Preferably, the inner surface roughness of the high-temperature alloy capillary is <0.8μm; Preferably, the outer surface roughness of the high-temperature alloy capillary is <0.4μm; Preferably, the straightness of the high-temperature alloy capillary is ≤0.5mm / m; Preferably, the room temperature mechanical properties of the high-temperature alloy capillary are: yield strength ≥ 500 MPa, tensile strength ≥ 900 MPa, and elongation ≥ 48%. Preferably, the high-temperature alloy capillary has a grain size grade ≥ 7, and the grain size difference of the high-temperature alloy capillary is ≤ 1 grade.

3. A method for preparing a high-temperature alloy capillary according to claim 1 or 2, characterized in that, The preparation method includes the following steps: (1) The raw materials are mixed according to the proportion of each element, and vacuum induction melting, electroslag remelting and forging are carried out in sequence to obtain a billet; (2) Inclusion detection and ultrasonic testing are performed on the billet; (3) The billet from step (2) is subjected to hot extrusion to obtain a rough tube; (4) The rough tube is subjected to a first cold rolling process and a first annealing process in sequence to obtain annealed tube material; (5) The annealed pipe is subjected to a second cold rolling process and a second annealing process in sequence to obtain a preliminary finished pipe; (6) The preliminary finished pipe is subjected to finishing and heat treatment in sequence to obtain a high-temperature alloy capillary tube with an outer diameter of 0.5~2mm and a wall thickness of 0.05~0.1mm.

4. The preparation method according to claim 3, characterized in that, The temperature of the vacuum induction melting process is 1500~1600℃; Preferably, the vacuum degree of the vacuum induction melting process is ≤2.6 Pa; Preferably, the vacuum induction melting process takes 20 to 50 minutes; Preferably, the electromagnetic stirring time in the vacuum induction melting process is 10-30 minutes; Preferably, the casting temperature in the vacuum induction melting process is 1480~1520℃; Preferably, the electroslag remelting process includes: grinding the vacuum induction ingot obtained from the vacuum induction melting process to obtain an induction electrode, and then welding the induction electrode to an auxiliary electrode and loading it into an electroslag remelting furnace for electroslag remelting. Preferably, the slag system used in the electroslag remelting process comprises CaF2, Al2O3, CaO, and MgO; Preferably, the mass ratio of CaF2, Al2O3, CaO and MgO in the slag system is (12~14):(2~4):(2~4):1; Preferably, the electroslag remelting process is carried out under an inert atmosphere; Preferably, the melting rate of the electroslag remelting process is 3~5 kg / min.

5. The preparation method according to claim 3 or 4, characterized in that, The forging billet processing includes: heating the electroslag remelted ingot to 1190~1210℃ in a heat treatment furnace, holding it at that temperature for ≥4h, and then forging it to obtain the billet. Preferably, the initial forging temperature of the forging billet treatment is ≥1050℃; Preferably, the final forging temperature of the forging blanking process is ≥900℃; Preferably, the forging ratio of the forging blanking process is 3 to 5.

6. The preparation method according to any one of claims 3-5, characterized in that, The temperature of the hot extrusion process is 1150~1200℃; Preferably, the extrusion ratio of the hot extrusion treatment is 5.5 to 7.09; Preferably, the extrusion speed of the hot extrusion process is ≤50mm / s; Preferably, the outer diameter of the rough pipe is 80~100mm; Preferably, the wall thickness of the rough pipe is 6-8 mm.

7. The preparation method according to any one of claims 3-6, characterized in that, The thickness deformation rate of the first cold rolling process is greater than that of the second cold rolling process; Preferably, the thickness deformation rate of the first cold rolling treatment is 10-40% greater than that of the second cold rolling treatment; Preferably, the thickness deformation rate of the first cold rolling process is 40-50%; Preferably, the rolling speed of the first cold rolling process is 30~60 r / min; Preferably, the feed rate of the first cold rolling process is 2~5mm / batch; Preferably, step (5) in the preparation method is repeated 1 to 5 times; Preferably, the thickness deformation rate of the second cold rolling treatment is 10-30%; Preferably, the rolling speed of the second cold rolling process is 20~40 r / min; Preferably, the feed rate for the second cold rolling process is 1~3 mm / batch; Preferably, the rolling oil temperature for the first cold rolling treatment and the second cold rolling treatment is independently 40~80°C; Preferably, the temperatures of the first annealing treatment and the second annealing treatment are each independently 1080~1120℃; Preferably, the time for the first annealing process and the second annealing process are each 10~60 min independently.

8. The preparation method according to any one of claims 3-7, characterized in that, The finishing process includes straightening, tube cutting, cleaning, and surface polishing performed sequentially. Preferably, the straightening speed is 1~5 m / min; Preferably, the straightness of the pre-finished pipe after the straightening treatment is ≤0.5mm / m; Preferably, the cleaning agent used in the cleaning process includes any one or a combination of at least two of anhydrous ethanol, a weak alkaline degreasing agent, or a phosphoric acid solution; Preferably, the surface roughness of the pre-finished pipe after the surface polishing treatment is <0.4μm; Preferably, the inner surface roughness of the pre-finished pipe after surface polishing is <0.8μm; Preferably, the temperature of the heat treatment is 960~1000℃; Preferably, the heat treatment time is 10-30 minutes.

9. The preparation method according to any one of claims 3-8, characterized in that, The preparation method includes the following steps: (1) The raw materials are mixed according to the proportion of each element, and vacuum induction melting, electroslag remelting and forging are carried out in sequence to obtain a billet; (2) Inclusion detection and ultrasonic testing are performed on the billet; (3) The billet from step (2) is subjected to hot extrusion treatment at a temperature of 1150~1200℃, an extrusion ratio of 5.5~7.09 and an extrusion speed of ≤50mm / s to obtain a rough tube with an outer diameter of 80~100mm and a wall thickness of 6~8mm. (4) The rough tube is subjected to a first cold rolling process with a thickness deformation rate of 40-50%, a rolling speed of 30-60 r / min, and a feed amount of 2-5 mm / time, and a first annealing process with a temperature of 1080-1120℃ and a time of 10-60 min to obtain the annealed tube. (5) The annealed pipe is subjected to a second cold rolling process with a thickness deformation rate of 10~30%, a rolling speed of 20~40 r / min, and a feed amount of 1~3 mm / time, and then subjected to a second annealing process with a temperature of 1080~1120℃ and a time of 10~60 min. The second cold rolling process and the second annealing process are repeated 1~5 times to obtain the preliminary finished pipe. (6) The preliminary finished pipe is subjected to straightening, cutting, cleaning, surface polishing and heat treatment at a temperature of 960~1000℃ for 10~30min in sequence to obtain a high-temperature alloy capillary with an outer diameter of 0.5~2mm and a wall thickness of 0.05~0.1mm.

10. The application of a high-temperature alloy capillary according to claim 1 or 2 in ultrapure fluid transport in aerospace engine fuel control systems and / or semiconductor devices.

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