A method for producing a titanium bronze alloy wire

Abstract

This invention belongs to the field of copper alloy preparation technology, and relates to a method for preparing titanium bronze alloy wire. The raw materials contain 1.75-2.25 wt% Ti, 0.4-0.6 wt% Cr, and the balance copper by mass percentage. The steps include: S1 material preparation; S2 vacuum casting; S3 forging; S4 hot extrusion; S5 drawing; S6 solution treatment; S7 cold drawing; and S8 annealing. This invention produces titanium bronze alloy wire with good strength and plasticity, high dimensional accuracy, smooth and uniform surface, and stable mechanical properties, which meets the requirements for copper alloy welding and forming wire. Furthermore, the preparation method is simple, suitable for large-scale industrial production, and reduces production costs.

Description

Technical Field

[0001] This invention belongs to the field of copper alloy preparation technology, and particularly relates to a method for preparing titanium bronze alloy wire. Background Technology

[0002] Titanium bronze alloy is a copper alloy material with high strength, hardness, and elasticity. Its performance is comparable to that of beryllium bronze. It has advantages such as excellent wear resistance, fatigue resistance, heat resistance, and corrosion resistance. It can withstand pressure processing in both hot and cold states, so it is widely used in electrical switches, relay components, vacuum tube sockets, precision gears, etc.

[0003] Given the excellent properties of titanium bronze, titanium bronze wire, as a special product, can be applied in fields such as marine development, weaponry, and aerospace where high strength, hardness, and conductivity are required. Currently, the titanium element mass fraction in the American standard grade C19900 / C19910 titanium bronze is 2.9-3.5 wt%. High strength can be achieved through work hardening and precipitation hardening, but cracking and wire breakage are prone to occur during wire processing. Chinese invention patent CN112458332A discloses a titanium bronze alloy rod, its preparation method, and its application. This titanium bronze alloy has good comprehensive properties, but this method cannot obtain titanium bronze wire with a diameter of less than 5.0 mm.

[0004] Therefore, there is a need for a method to prepare titanium bronze alloy wire that has high dimensional accuracy, smooth and uniform surface, and stable mechanical properties, so as to meet the requirements for wire used in copper alloy welding and forming. Summary of the Invention

[0005] To address the shortcomings of the existing technology, this invention provides a method for preparing titanium bronze alloy wire, the specific technical solution of which is as follows:

[0006] A method for preparing titanium bronze alloy wire, wherein the mass percentage of each element in the raw material is 1.75-2.25 wt% Ti, 0.4-0.6 wt% Cr, and the balance copper;

[0007] The steps include: S1 material preparation; S2 vacuum casting; S3 forging; S4 hot extrusion; S5 drawing; S6 solution treatment; S7 cold drawing; and S8 annealing.

[0008] This invention uses a low titanium content to avoid the formation of oxide slag during the smelting process due to excessive titanium content, which would cause component segregation. The addition of a small amount of Cr can hinder grain growth during hot working, refine the grains, and improve cold working performance. This invention can produce titanium bronze wire with a diameter of less than Φ5.0mm, which has good strength and plasticity, can meet the requirements of wire for automatic welding and forming of copper alloys, and the preparation method is simple and suitable for large-scale industrial production.

[0009] Furthermore, the preparation method of the titanium bronze alloy wire specifically includes the following steps:

[0010] S1 Material Preparation: Clean and dry the raw materials, mix them according to the element mass percentage, clean and dry the inner walls of the crucible and casting mold, spray the casting mold with release agent and bake it for later use.

[0011] S2 Vacuum Melting: The raw materials are vacuum melted, and after slag removal, the molten copper is introduced into the intermediate ladle in the vacuum casting chamber. Then the molten copper is poured into the mold, and after cooling and solidification, it is demolded to obtain a copper alloy ingot.

[0012] S3 Forging: After removing the riser and bottom of the copper alloy ingot, it is heated and held at a certain temperature before forging to obtain a copper alloy billet.

[0013] S4 hot extrusion: After removing the oxide scale from the copper alloy billet, it is hot extruded and cooled in water to obtain copper alloy rods;

[0014] S5 drawing: Cold drawing of copper alloy bars to obtain copper alloy wire blanks;

[0015] S6 solution treatment: The copper alloy wire blank is solution treated, water cooled, and then the oxide scale is removed by peeling.

[0016] S7 Cold Drawing: Copper alloy wire is obtained by drawing copper alloy wire blanks that have been stripped of their oxide scale in multiple passes.

[0017] S8 Annealing: Annealing copper alloy wire in a protective atmosphere.

[0018] In the preparation of titanium bronze alloy wire, the casting and pouring processes are carried out in a vacuum environment, which can reduce the burning and oxidation of elements and ensure the accuracy of the composition. The addition of a forging process before hot extrusion avoids defects such as cracks caused by coarse grains in the cast structure during hot extrusion or wire drawing.

[0019] Furthermore, the raw materials are electrolytic copper plates, chromium copper alloys, and titanium copper alloys.

[0020] Furthermore, in step S1, the baking temperature of the casting mold is ≥200℃, the thickness of the sprayed release agent is 1-3mm, and the release agent is a zircon powder release agent.

[0021] Furthermore, in step S2, when the raw materials are vacuum melted, the electrolytic copper plate and chromium-copper alloy are first melted, and then titanium-copper alloy is added and heated to 1250-1280℃, stirred and melted. The vacuum degree of vacuum melting is -0.1MPa and the melting temperature is 1250-1280℃; the vacuum degree of vacuum casting chamber is -0.1MPa and the casting temperature is 1200-1210℃.

[0022] Furthermore, in step S3, the heating and holding temperature is 850-900℃, and the heating and holding time is 1-2 hours; the forging process involves three upsetting and three drawing operations.

[0023] In the preparation of titanium bronze alloy wire, this invention employs multiple upsetting and drawing processes to refine the grains, improve the uniformity of the microstructure, and further avoid defects such as cracks caused by coarse grains in the cast microstructure during hot extrusion or wire drawing.

[0024] Furthermore, in step S4, the hot extrusion temperature is 850-900℃, the holding time is 1-2h, the extrusion speed is 0.8-2m / s, and the extrusion ratio is 18-35%.

[0025] Furthermore, in step S5, the deformation amount of a single cold drawing is 20-40%.

[0026] Furthermore, in step S6, the solution temperature is 800-850℃, and the holding time is 20-45 minutes.

[0027] Furthermore, in step S7, the cold drawing is performed at room temperature, using a single-die or multi-die multi-pass drawing method, with a single-pass deformation of 20-40%. Through single-die or multi-die multi-pass drawing, the diameter Φ of the copper alloy wire can reach 1.0-2.0 mm.

[0028] Furthermore, in step S8, the annealing temperature is 400-500℃, the holding time is 6-8h, and the protective atmosphere is nitrogen.

[0029] The beneficial effects of this invention are as follows:

[0030] This invention produces titanium bronze alloy wire with good strength and plasticity, high dimensional accuracy, smooth and uniform surface, and stable mechanical properties, which can meet the requirements of copper alloy welding and forming wire. Moreover, the preparation method is simple, suitable for large-scale industrial production, and reduces production costs. Attached Figure Description

[0031] Figure 1 This is a flowchart illustrating the preparation process of the titanium bronze alloy wire of the present invention.

[0032] Figure 2 The image shown is a physical photograph of a product according to an embodiment of the present invention.

[0033] Figure 3 Metallographic image of the product according to an embodiment of the present invention;

[0034] Figure 4 The image shown is a physical photograph of the product used in this invention as a comparative example. Detailed Implementation

[0035] The principles and features of the present invention are described below with reference to embodiments. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0036] Example:

[0037] like Figure 1 As shown, a method for preparing titanium bronze alloy wire includes the following steps:

[0038] S1 Material Preparation: Clean and dry the raw materials electrolytic copper plate, chromium copper alloy, and titanium copper alloy, and mix them according to the following element weight percentages: Ti 1.85%, Cr 0.4%, balance copper; clean and dry the inner wall of the crucible and casting mold, then spray and brush the inner wall of the casting mold with a uniform zircon powder release agent with a thickness of about 2mm, and then bake it at a temperature of 200-300℃.

[0039] S2 Vacuum Casting: The raw materials are melted in a vacuum induction furnace at a vacuum pressure of -0.1 MPa and a melting temperature of 1270°C. After slag removal, the molten copper is introduced into the intermediate ladle in a vacuum casting chamber at a vacuum pressure of -0.1 MPa and poured into the mold at a pouring temperature of 1210°C. After cooling and solidification, the mold is removed to obtain a copper alloy ingot.

[0040] S3 Forging: After removing the riser and bottom of the copper alloy ingot, it is heated to 900℃ in a box furnace and held for 2 hours. It is then hot-forged in an air hammer at a final forging temperature of 840℃. The ingot is upsetting and drawing are performed 3 times each to obtain a copper alloy billet.

[0041] S4 Hot Extrusion: After removing the oxide scale by turning the copper alloy billet, it is hot extruded in a 2800T horizontal extrusion press at a temperature of 890℃, a holding time of 1.5h, an extrusion speed of 1.5m / s, an extrusion ratio of 19%, and water-sealed cooling to obtain copper alloy rods.

[0042] S5 drawing: Copper alloy bars are drawn on a 50T drawing machine with a single deformation of 30% to obtain copper alloy wire blanks.

[0043] S6 Solution Treatment: The copper alloy wire blank is solution treated in a box furnace at a temperature of 850°C for 30 minutes, then cooled with water, and the oxide scale is removed.

[0044] S7 Cold Drawing: Copper alloy wire blanks with peeled and de-oxidized surfaces are drawn one pass at a time using an inverted wire drawing machine and a pulley wire drawing machine to obtain copper alloy wire. The deformation per pass is ≤40%. The blank size variation is Φ20-Φ7mm for the inverted wire drawing machine and Φ7-Φ1.6mm for the pulley wire drawing machine.

[0045] S8 Annealing: The copper alloy wire is heated to 460℃ in a vertical bell furnace, held for 8 hours, and annealed under nitrogen protection.

[0046] Comparative example:

[0047] A method for preparing titanium bronze alloy wire includes the following steps:

[0048] S1 Material Preparation: Clean and dry the raw materials electrolytic copper plate, chromium copper alloy, and titanium copper alloy, and mix them according to the following element weight percentages: Ti 1.85%, Cr 0.4%, balance copper; clean and dry the inner wall of the crucible and casting mold, then spray and brush the inner wall of the casting mold with a uniform zircon powder release agent with a thickness of about 2mm, and then bake it at a temperature of 200-300℃.

[0049] S2 Non-Vacuum Melting: The raw materials are melted in a vacuum induction furnace at a vacuum of -0.1 MPa and a melting temperature of 1270°C. After slag removal, the molten copper is introduced into the intermediate ladle in the casting chamber and poured into the mold at a pouring temperature of 1210°C. After cooling and solidification, the mold is removed to obtain a copper alloy ingot.

[0050] S3 Hot Extrusion: After removing the oxide scale from the copper alloy ingot by turning, it is hot extruded in a 2800T horizontal extrusion press at a temperature of 890℃, a holding time of 1.5h, an extrusion speed of 1.5m / s, an extrusion ratio of 19%, and water-sealed cooling to obtain copper alloy bars.

[0051] S4 drawing: Copper alloy bars are drawn on a 50T drawing machine with a single deformation of 30% to obtain copper alloy wire blanks.

[0052] S5 Solution Treatment: The copper alloy wire blank is solution treated in a box furnace at a temperature of 890℃ for 30 minutes, then cooled with water, and the oxide scale is removed.

[0053] S6 Cold Drawing: Copper alloy wire blanks with peeled and de-oxidized surfaces are drawn one pass at a time using an inverted drawing machine and a pulley drawing machine to obtain copper alloy wire. The deformation per pass is ≤40%. The blank size variation is Φ20-Φ7mm for the inverted drawing machine and Φ7-Φ1.6mm for the pulley drawing machine.

[0054] S7 Annealing: The copper alloy wire is heated to 460℃ in a vertical bell furnace, held for 8 hours, and annealed under nitrogen protection.

[0055] The performance of the titanium bronze alloy wires obtained in the examples and comparative examples was tested, and the test results are shown in Table 1.

[0056] Table 1. Performance Test Results of Examples and Comparative Examples

[0057]

[0058] "-" indicates that it was not detected because the comparative product had a crack defect.

[0059] As can be seen from the data in Table 1, compared with the improved process of the comparative example, the titanium bronze alloy wire of the present invention has good strength, plasticity, and electrical conductivity. Figure 2 It can be seen that the titanium bronze alloy wire of this invention has a smooth and uniform surface, free from defects such as cracks and broken wires; Figure 3 As can be seen, aging refines the grains, with chromium-titanium compounds evenly distributed between the grains, and no defects such as cracks or inclusions. Therefore, the titanium bronze alloy wire prepared by this invention can meet the requirements for wire used in copper alloy welding and forming, and the preparation method is simple and suitable for large-scale industrial production.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing titanium bronze alloy wire, characterized in that, The raw materials contain the following elemental mass percentages: 1.75-1.85 wt% Ti, 0.4-0.6 wt% Cr, and balance copper. The steps include: S1 Material preparation; S2 Vacuum casting; S3 Forging; S4 Hot extrusion; S5 Drawing; S6 Solution treatment; S7 Cold drawing; S8 Annealing. Specifically, the steps include the following: S1 Material Preparation: Clean and dry the raw materials, mix them according to the element mass percentage, clean and dry the inner walls of the crucible and casting mold, spray the casting mold with release agent and bake it for later use. S2 Vacuum Melting: The raw materials are vacuum melted, and after slag removal, the molten copper is introduced into the intermediate ladle in the vacuum casting chamber. Then the molten copper is poured into the mold, and after cooling and solidification, it is demolded to obtain a copper alloy ingot. S3 Forging: After removing the riser and bottom of the copper alloy ingot, it is heated and held at a certain temperature before forging to obtain a copper alloy billet. S4 hot extrusion: After removing the oxide scale from the copper alloy billet, it is hot extruded and cooled in water to obtain copper alloy rods; S5 drawing: Cold drawing of copper alloy bars to obtain copper alloy wire blanks; S6 solution treatment: The copper alloy wire blank is solution treated, water cooled, and then the oxide scale is removed by peeling. S7 Cold Drawing: Copper alloy wire is obtained by drawing copper alloy wire blanks that have been stripped of their oxide scale in multiple passes. S8 annealing: Annealing copper alloy wire in a protective atmosphere; In step S2, when the raw materials are vacuum melted, the electrolytic copper plate and chromium-copper alloy are first melted, and then titanium-copper alloy is added and heated to 1250-1280℃. The mixture is stirred until melted. The vacuum of the vacuum melting chamber is -0.1MPa and the melting temperature is 1250-1280℃. The vacuum of the vacuum casting chamber is -0.1MPa and the casting temperature is 1200-1210℃. In step S3, the heating and holding temperature is 850-900℃, and the heating and holding time is 1-2 hours; the forging process involves three upsetting and three drawing operations. In step S4, the hot extrusion temperature is 850-900℃, the holding time is 1-2 hours, the extrusion speed is 0.8-2 m / s, and the extrusion ratio is 18-35%. In step S6, the solution temperature is 800-850℃ and the holding time is 20-45min; In step S7, the cold drawing is performed at room temperature, using a single-die or multi-die multi-pass drawing method, with a single-pass deformation of 20-40%. Through single-die or multi-die multi-pass drawing, the diameter of copper alloy wire can be Φ up to 1.0-2.0mm.

2. The method for preparing titanium bronze alloy wire according to claim 1, characterized in that, The raw materials are electrolytic copper plates, chromium copper alloys, and titanium copper alloys.

3. The method for preparing titanium bronze alloy wire according to claim 2, characterized in that, In step S1, the baking temperature of the casting mold is ≥200℃, the thickness of the release agent is 1-3mm, and the release agent is zircon powder release agent.

4. The method for preparing titanium bronze alloy wire according to claim 1, characterized in that, In step S8, the annealing temperature is 400-500℃, the holding time is 6-8h, and the protective atmosphere is nitrogen.

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