Ultra-high-strength conductive copper-titanium alloy and preparation method thereof

Abstract

The present invention belongs to the technical field of beryllium-free copper alloy materials, and provides an ultra-high-strength conductive copper-titanium alloy and a preparation method thereof. The present invention takes Cu as the matrix, adds Cr and Mg, effectively improves the strength and conductivity of the alloy, Mg is solid-dissolved in the matrix, plays a solid solution strengthening role, Cr and Ti can form Cr2Ti intermetallic compounds, thereby improving the strength and conductivity of the alloy; combined with combined aging treatment, the volume fraction of β-Cu4Ti precipitated phase can be increased while reducing production costs, thereby greatly improving the conductivity of the alloy; combined with hot rolling and cold rolling, it is beneficial to obtain a high-density, uniformly distributed β-Cu4Ti phase, thereby improving the strength and conductivity of the copper-titanium alloy. The results of the embodiment show that the hardness of the ultra-high-strength conductive copper-titanium alloy prepared by the preparation method provided by the present invention can reach 310HV, and the conductivity can reach 35%IACS.

Description

Technical Field

[0001] The present invention relates to the technical field of beryllium-free copper alloy materials, and in particular to an ultra-high-strength conductive copper-titanium alloy and a preparation method thereof. Background Art

[0002] Beryllium bronze is a typical precipitation-hardening alloy with excellent comprehensive properties, earning it the reputation of the king of elastic copper alloys. It boasts high strength, high elasticity, high hardness, high wear resistance, excellent electrical and thermal conductivity, and no sparking when impacted. It is widely used in precision instrument manufacturing, connectors, and conductive springs. However, beryllium bronze is prone to producing beryllium dust during the smelting process, which poses a serious health hazard. Furthermore, when operating at temperatures exceeding 200°C, beryllium bronze experiences a stress relaxation rate exceeding 40%, leading to relay failure. Furthermore, beryllium reserves in the Earth's crust are limited, making the alloy costly. Therefore, there is an urgent need to find alternative materials to beryllium bronze.

[0003] Beryllium-free copper-titanium alloy is also a typical precipitation-hardening alloy. The solute atomic Ti has a strong solid solution strengthening effect on the copper-titanium alloy. The peak aging α-Cu4Ti phase is coherent with the matrix, which has a good dispersion strengthening effect. The strength of copper-titanium alloy is comparable to that of beryllium copper, making it an ideal alternative material.

[0004] The mechanical properties of copper-titanium alloy are comparable to those of beryllium copper, but its electrical conductivity is lower than that of beryllium copper. In order to improve the performance of the product, the prior art proposes methods of adding different trace elements, rolling and aging. Common third alloying elements are Al, Sn, Zn, Zr, Ni, and Cr. For example, patent CN201510108135.4 discloses a high-strength copper-titanium alloy and a preparation method thereof, patent CN202010620874.2 discloses a copper-titanium alloy and a preparation method thereof, and patent CN20201087436.3 discloses an elastic copper-titanium alloy and a preparation method thereof. However, the above patents are not ideal in balancing the strength and conductivity of copper-titanium alloys. Therefore, there is an urgent need for a method that can ensure the high strength of copper-titanium alloys while improving their electrical conductivity. Summary of the Invention

[0005] The object of the present invention is to provide an ultra-high-strength conductive copper-titanium alloy and a preparation method thereof. The ultra-high-strength conductive copper-titanium alloy prepared by the preparation method provided by the present invention has high strength and high conductivity.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] The present invention provides a method for preparing an ultra-high-strength conductive copper-titanium alloy, comprising the following steps:

[0008] (1) melting and casting the raw materials of ultra-high-strength conductive copper-titanium alloy in sequence to obtain a copper-titanium alloy ingot;

[0009] (2) subjecting the copper-titanium alloy ingot obtained in step (1) to solution treatment, hot rolling and first aging treatment in sequence to obtain a copper-titanium alloy plate;

[0010] (3) subjecting the copper-titanium alloy plate obtained in step (2) to a first cold rolling, a second aging treatment, and a second cold rolling in sequence to obtain an ultra-high-strength conductive copper-titanium alloy;

[0011] Calculated by mass percentage, the ultra-high-strength conductive copper-titanium alloy comprises: Ti 1-5%, Cr 0.1-3%, Mg 0.1-3% and the balance Cu.

[0012] Preferably, the smelting temperature in step (1) is 1150-1350°C; and the casting temperature is 1100-1250°C.

[0013] Preferably, the temperature of the solution treatment in step (2) is 700-900° C., and the holding time of the solution treatment is 4-8 hours.

[0014] Preferably, in step (2), the hot rolling temperature is 600-850° C., the hot rolling holding time is 1-3 hours, and the hot rolling processing rate is 50-80%.

[0015] Preferably, the first aging treatment in step (2) is specifically: first keeping warm at 550-600°C for 1-3 hours, then keeping warm at 500-550°C for 1-3 hours, and finally keeping warm at 400-450°C for 8-12 hours.

[0016] Preferably, the second aging treatment in step (3) is specifically as follows: first, keeping warm at 400-450°C for 1-3 hours, then keeping warm at 350-380°C for 1-3 hours, and finally keeping warm at 320-350°C for 6-8 hours.

[0017] Preferably, the temperatures of the first cold rolling and the second cold rolling in step (3) are independently room temperature.

[0018] Preferably, the deformation amounts of the first cold rolling and the second cold rolling in step (3) are independently 40 to 70%.

[0019] The present invention also provides an ultra-high-strength conductive copper-titanium alloy prepared by the preparation method described in the above technical solution.

[0020] The present invention provides a preparation method of an ultra-high-strength conductive copper-titanium alloy, comprising the following steps: (1) smelting and casting raw materials of the ultra-high-strength conductive copper-titanium alloy in sequence to obtain a copper-titanium alloy ingot; (2) subjecting the copper-titanium alloy ingot obtained in step (1) to solution treatment, hot rolling and a first aging treatment in sequence to obtain a copper-titanium alloy plate; (3) subjecting the copper-titanium alloy plate obtained in step (2) to a first cold rolling, a second aging treatment and a second cold rolling in sequence to obtain an ultra-high-strength conductive copper-titanium alloy; the ultra-high-strength conductive copper-titanium alloy comprises, in terms of mass percentage, 1-5% Ti, 0.1-3% Cr, 0.1-3% Mg and a balance of Cu. The present invention uses Cu as the matrix and effectively improves the strength and conductivity of the alloy by adding alloying elements Cr and Mg. The Mg element is dissolved in the matrix and plays a solid solution strengthening role. Cr and Ti can form Cr2Ti intermetallic compounds, which reduces the solid solution Ti content and improves the conductivity of the alloy. In addition, the intermetallic compounds hinder dislocation movement during the later rolling process, increase the dislocation density, and thus improve the strength and conductivity of the alloy. Combined with combined aging treatment, the volume fraction of the β-Cu4Ti precipitated phase can be increased while reducing production costs, thereby greatly improving the conductivity of the alloy. Combined with hot rolling and cold rolling, it is conducive to obtaining a high-density, uniformly distributed β-Cu4Ti phase, thereby improving the strength and conductivity of the copper-titanium alloy. The results of the embodiment show that the ultra-high-strength conductive copper-titanium alloy prepared by the preparation method provided by the present invention has a hardness of up to 310HV and a conductivity of up to 35%IACS. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a SEM image of the ultra-high-strength conductive copper-titanium alloy prepared in Example 1 of the present invention;

[0022] Figure 2 This is a SEM image of the copper-titanium alloy prepared in Comparative Example 1 of the present invention;

[0023] Figure 3 This is a SEM image of the ultra-high-strength conductive copper-titanium alloy prepared in Example 2 of the present invention;

[0024] Figure 4 This is a SEM image of the copper-titanium alloy prepared in Comparative Example 2 of the present invention;

[0025] Figure 5 This is a SEM image of the ultra-high-strength conductive copper-titanium alloy prepared in Example 3 of the present invention;

[0026] Figure 6 This is the SEM image of the copper-titanium alloy prepared in Comparative Example 3 of the present invention. DETAILED DESCRIPTION

[0027] The present invention provides a method for preparing an ultra-high-strength conductive copper-titanium alloy, comprising the following steps:

[0028] (1) melting and casting the raw materials of ultra-high-strength conductive copper-titanium alloy in sequence to obtain a copper-titanium alloy ingot;

[0029] (2) subjecting the copper-titanium alloy ingot obtained in step (1) to solution treatment, hot rolling and first aging treatment in sequence to obtain a copper-titanium alloy plate;

[0030] (3) subjecting the copper-titanium alloy plate obtained in step (2) to a first cold rolling, a second aging treatment, and a second cold rolling in sequence to obtain an ultra-high-strength conductive copper-titanium alloy;

[0031] Calculated by mass percentage, the ultra-high-strength conductive copper-titanium alloy comprises: Ti 1-5%, Cr 0.1-3%, Mg 0.1-3% and the balance Cu.

[0032] The invention sequentially smelts and casts raw materials of ultra-high-strength conductive copper-titanium alloy to obtain copper-titanium alloy ingots.

[0033] The present invention has no special limitation on the smelting and casting operations, and the smelting and casting technical solutions well known to those skilled in the art can be adopted.

[0034] In the present invention, the smelting temperature is preferably 1150-1350° C., more preferably 1150-1250° C. In the present invention, the smelting equipment is preferably a vacuum induction furnace.

[0035] In the present invention, the order of adding materials in the smelting is preferably: first adding Cu, then adding Ti, Cr and Mg in sequence.

[0036] In the present invention, the casting temperature is preferably 1100-1250°C, more preferably 1150-1200°C.

[0037] After casting, the present invention preferably mills the cast product. The present invention does not specifically limit the milling operation, and any milling technique known to those skilled in the art can be employed. Milling removes casting defects from the product surface.

[0038] After obtaining the copper-titanium alloy ingot, the present invention sequentially performs solid solution treatment, hot rolling and first aging treatment on the copper-titanium alloy ingot to obtain a copper-titanium alloy plate.

[0039] The present invention does not specifically limit the operation of the solution treatment, and the technical scheme of the solution treatment well known to those skilled in the art can be used. The present invention uses the solution treatment to dissolve the solute atoms in the copper matrix as much as possible, preparing for the subsequent aging treatment, thereby controlling the formation of the precipitated phase.

[0040] In the present invention, the temperature of the solution treatment is preferably 700-900° C., more preferably 850-900° C.; the holding time of the solution treatment is preferably 4-8 h, more preferably 6-8 h.

[0041] In the present invention, the cooling method after the solution treatment is preferably room temperature water cooling.

[0042] The present invention does not specifically limit the hot rolling process, and hot rolling techniques well known to those skilled in the art may be employed. The hot rolling process employed in the present invention can refine the matrix grains, thereby facilitating the formation of a high-density, uniformly distributed β-Cu4Ti phase, thereby improving the strength and electrical conductivity of the copper-titanium alloy.

[0043] In the present invention, the hot rolling temperature is preferably 600-850°C, more preferably 700-800°C; the hot rolling holding time is preferably 1-3h, more preferably 2-3h; the hot rolling processing rate is preferably 50-80%, more preferably 60-70%.

[0044] In the present invention, the cooling method after hot rolling is preferably air cooling.

[0045] In the present invention, the first aging treatment is preferably: first, holding at 550-600°C for 1-3 hours, then holding at 500-550°C for 1-3 hours, and finally holding at 400-450°C for 8-12 hours; more preferably, first, holding at 580-600°C for 2-3 hours, then holding at 520-550°C for 2-3 hours, and finally holding at 420-450°C for 8-10 hours. By adopting a combined aging treatment of the first and second aging treatments, the present invention can increase the volume fraction of the β-Cu4Ti precipitate phase while reducing production costs, thereby significantly improving the electrical conductivity of the alloy.

[0046] In the present invention, the cooling method after the first aging treatment is preferably air cooling or water cooling.

[0047] After obtaining the copper-titanium alloy plate, the present invention sequentially performs a first cold rolling, a second aging treatment, and a second cold rolling on the copper-titanium alloy plate to obtain an ultra-high-strength conductive copper-titanium alloy.

[0048] In the present invention, the second aging treatment is preferably: first, keep at 400-450°C for 1-3 hours, then keep at 350-380°C for 1-3 hours, and finally keep at 320-350°C for 6-8 hours; more preferably, keep at 420-450°C for 1-2 hours, then keep at 360-380°C for 1-2 hours, and finally keep at 330-350°C for 6-8 hours. By adopting a combined aging treatment of the first and second aging treatments, the present invention can increase the volume fraction of the β-Cu4Ti precipitate phase while reducing production costs, thereby significantly improving the electrical conductivity of the alloy.

[0049] In the present invention, the cooling method after the second aging treatment is preferably air cooling.

[0050] The present invention does not specifically limit the first and second cold rolling processes; cold rolling techniques familiar to those skilled in the art may be employed. The present invention combines hot and cold rolling to refine the matrix grains, thereby facilitating the formation of a high-density, uniformly distributed β-Cu4Ti phase and improving the strength and electrical conductivity of the copper-titanium alloy.

[0051] In the present invention, the temperatures of the first cold rolling and the second cold rolling are preferably independently room temperature.

[0052] In the present invention, the deformation amounts of the first cold rolling and the second cold rolling are preferably independently 40 to 70%, more preferably 40 to 50%.

[0053] In the present invention, the ultra-high-strength conductive copper-titanium alloy comprises 1-5%, preferably 2-4%, of Ti, by mass percentage. The Ti in the present invention can form a Cr2Ti intermetallic compound with Cr. The intermetallic compound hinders dislocation motion during subsequent rolling, increasing dislocation density and thereby improving the strength and conductivity of the copper-titanium alloy.

[0054] In the present invention, the ultra-high-strength conductive copper-titanium alloy comprises 0.1-3% Cr, preferably 0.5-2% Cr, by mass percentage. Cr and Ti in the present invention form a Cr2Ti intermetallic compound, which reduces the solid-solution Ti content and improves the conductivity of the alloy.

[0055] In the present invention, the ultra-high-strength conductive copper-titanium alloy comprises 0.1-3% Mg, preferably 0.5-2% Mg, by mass percentage. The Mg element in the present invention is solid-dissolved in the matrix, playing a solid-solution strengthening role, and can effectively improve the strength and conductivity of the copper-titanium alloy.

[0056] In the present invention, the ultra-high-strength conductive copper-titanium alloy further includes a balance of Cu in terms of mass percentage. The Cu in the present invention is the alloy matrix.

[0057] The present invention uses Cu as a matrix and effectively improves the strength and electrical conductivity of the alloy by adding alloying elements Cr and Mg. The Mg element is solid-dissolved in the matrix and plays a solid-solution strengthening role. Cr and Ti can form a Cr2Ti intermetallic compound, which reduces the solid-solution Ti content and improves the electrical conductivity of the alloy. In addition, the intermetallic compound hinders dislocation movement during the subsequent rolling process, increases the dislocation density, and thus improves the strength and electrical conductivity of the alloy. Combined with a combined aging treatment, the volume fraction of the β-Cu4Ti precipitated phase can be increased while reducing production costs, thereby significantly improving the electrical conductivity of the alloy. Combined with hot rolling and cold rolling, it is beneficial to obtain a high-density, uniformly distributed β-Cu4Ti phase, thereby improving the strength and electrical conductivity of the copper-titanium alloy.

[0058] The present invention also provides an ultra-high-strength conductive copper-titanium alloy prepared by the preparation method described in the above technical solution.

[0059] The ultra-high-strength conductive copper-titanium alloy provided by the present invention has high strength and high conductivity.

[0060] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions of the present invention. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0061] Example 1

[0062] The composition of the ultra-high-strength conductive copper-titanium alloy is, by mass percentage, 4% Ti, 0.5% Cr, 0.5% Mg, and the balance is copper;

[0063] Preparation method:

[0064] (1) First, Cu is added into a vacuum induction furnace for smelting at a smelting temperature of 1250°C. After melting, Ti is added and stirred thoroughly. Before being discharged from the furnace, Cr and Mg are added into the melt and stirred thoroughly before casting at a casting temperature of 1150°C. After milling, a copper-titanium alloy ingot is obtained.

[0065] (2) subjecting the copper-titanium alloy ingot obtained in step (1) to solution treatment at 900° C., holding the temperature for 4 h, and water-cooling at room temperature; and then hot rolling at 800° C., holding the temperature for 3 h, with a processing rate of 70%, to obtain a copper-titanium alloy plate;

[0066] (3) The copper-titanium alloy plate obtained in step (2) is first kept at 600° C. for 3 h, then kept at 550° C. for 3 h, and finally kept at 450° C. for 8 h, and water quenched at room temperature; then, a first cold rolling is performed at room temperature, with a deformation of 40% in the first cold rolling, to obtain a first cold-rolled copper-titanium alloy plate;

[0067] (4) The first cold-rolled copper-titanium alloy plate obtained in step (3) is first kept at 450°C for 1 hour, then kept at 380°C for 1 hour, and finally kept at 350°C for 8 hours, and air-cooled; then a second cold rolling is performed at room temperature, and the deformation of the second cold rolling is 40%, thereby obtaining an ultra-high-strength conductive copper-titanium alloy.

[0068] Figure 1 This is the SEM image of the ultra-high strength conductive copper-titanium alloy prepared in this embodiment. Figure 1 It can be seen that after combined aging, the lamellar β-Cu4Ti phase dominates and appears alternately with the copper matrix phase.

[0069] Comparative Example 1

[0070] The composition of the ultra-high-strength conductive copper-titanium alloy is, by mass percentage, 4% Ti, 0.5% Cr, 0.5% Mg, and the balance is copper;

[0071] Preparation method:

[0072] (1) First, Cu is added into a vacuum induction furnace for smelting at a smelting temperature of 1250°C. After melting, Ti is added and stirred thoroughly. Before being discharged from the furnace, Cr and Mg are added into the melt and stirred thoroughly before casting at a casting temperature of 1150°C. After milling, a copper-titanium alloy ingot is obtained.

[0073] (2) subjecting the copper-titanium alloy ingot obtained in step (1) to solution treatment at 900° C., holding the temperature for 4 h, and water-cooling at room temperature; and then hot rolling at 800° C., holding the temperature for 3 h, with a processing rate of 70%, to obtain a copper-titanium alloy plate;

[0074] (3) Isothermally aging the copper-titanium alloy plate obtained in step (2) at 450° C. for 100 h to obtain a copper-titanium alloy.

[0075] Figure 2 This is the SEM image of the copper-titanium alloy prepared in Comparative Example 1. Figure 2 It can be seen that after aging at 450℃ for 100h, there is only a small amount of precipitated phase on the grain boundaries in the microstructure, and the main phase is copper matrix.

[0076] Example 2

[0077] The composition of the ultra-high-strength conductive copper-titanium alloy is, by mass percentage, 4% Ti, 0.5% Cr, 1% Mg, and the balance is copper;

[0078] Preparation method:

[0079] (1) First, Cu is added into a vacuum induction furnace for smelting at a smelting temperature of 1250°C. After melting, Ti is added and stirred thoroughly. Before being discharged from the furnace, Cr and Mg are added into the melt and stirred thoroughly before casting at a casting temperature of 1200°C. The copper-titanium alloy ingot is obtained by milling the surface.

[0080] (2) subjecting the copper-titanium alloy ingot obtained in step (1) to solution treatment at 850° C., holding the temperature for 4 hours, and water-cooling at room temperature; and then hot rolling at 700° C., holding the temperature for 3 hours, with a processing rate of 60%, to obtain a copper-titanium alloy plate;

[0081] (3) The copper-titanium alloy plate obtained in step (2) is first kept at 600° C. for 3 h, then kept at 550° C. for 3 h, and finally kept at 450° C. for 12 h, and air-cooled; then, a first cold rolling is performed at room temperature, with a deformation amount of 50%, to obtain a first cold-rolled copper-titanium alloy plate;

[0082] (4) The first cold-rolled copper-titanium alloy plate obtained in step (3) is first kept at 450°C for 3 hours, then kept at 380°C for 3 hours, and finally kept at 350°C for 8 hours, and air-cooled; then a second cold rolling is performed at room temperature, and the deformation amount of the second cold rolling is 40%, thereby obtaining an ultra-high-strength conductive copper-titanium alloy.

[0083] Figure 3 This is the SEM image of the ultra-high strength conductive copper-titanium alloy prepared in this embodiment. Figure 3 It can be seen that after combined aging, the lamellar β-Cu4Ti phase dominates and appears alternately with the copper matrix phase.

[0084] Comparative Example 2

[0085] The composition of the ultra-high-strength conductive copper-titanium alloy is, by mass percentage, 4% Ti, 0.5% Cr, 1% Mg, and the balance is copper;

[0086] Preparation method:

[0087] (1) First, Cu is added into a vacuum induction furnace for smelting at a smelting temperature of 1250°C. After melting, Ti is added and stirred thoroughly. Before being discharged from the furnace, Cr and Mg are added into the melt and stirred thoroughly before casting at a casting temperature of 1200°C. The copper-titanium alloy ingot is obtained by milling the surface.

[0088] (2) subjecting the copper-titanium alloy ingot obtained in step (1) to solution treatment at 850° C., holding the temperature for 4 hours, and water-cooling at room temperature; and then hot rolling at 700° C., holding the temperature for 3 hours, with a processing rate of 60%, to obtain a copper-titanium alloy plate;

[0089] (3) Isothermally aging the copper-titanium alloy plate obtained in step (2) at 450° C. for 100 h to obtain a copper-titanium alloy.

[0090] Figure 4 This is the SEM image of the copper-titanium alloy prepared in Comparative Example 2. Figure 4 It can be seen that after aging at 450℃ for 100h, there is a very small amount of precipitated phase on the grain boundary in the microstructure, which is mainly composed of copper matrix phase.

[0091] Example 3

[0092] The composition of the ultra-high-strength conductive copper-titanium alloy is, by mass percentage, 4% Ti, 1% Cr, 0.5% Mg, and the balance is copper;

[0093] Preparation method:

[0094] (1) First, Cu is added into a vacuum induction furnace for smelting at a smelting temperature of 1250°C. After melting, Ti is added and stirred thoroughly. Before being discharged from the furnace, Cr and Mg are added into the melt and stirred thoroughly before casting at a casting temperature of 1200°C. The copper-titanium alloy ingot is obtained by milling the surface.

[0095] (2) subjecting the copper-titanium alloy ingot obtained in step (1) to solution treatment at 850° C., holding the temperature for 8 h, and water-cooling at room temperature; and then hot rolling at 700° C., holding the temperature for 3 h, with a processing rate of 60%, to obtain a copper-titanium alloy plate;

[0096] (3) The copper-titanium alloy plate obtained in step (2) is first kept at 600° C. for 3 hours, then kept at 550° C. for 3 hours, and finally kept at 450° C. for 9 hours, and air-cooled; then, a first cold rolling is performed at room temperature, and the deformation amount of the first cold rolling is 50%, thereby obtaining a first cold-rolled copper-titanium alloy plate;

[0097] (4) The first cold-rolled copper-titanium alloy plate obtained in step (3) is first kept at 450°C for 1 hour, then kept at 380°C for 2 hours, and finally kept at 350°C for 8 hours, and air-cooled; then a second cold rolling is performed at room temperature, and the deformation of the second cold rolling is 45%, thereby obtaining an ultra-high-strength conductive copper-titanium alloy.

[0098] Figure 5 This is the SEM image of the ultra-high strength conductive copper-titanium alloy prepared in this embodiment. Figure 5 It can be seen that after combined aging, the lamellar β-Cu4Ti phase dominates and appears alternately with the copper matrix phase.

[0099] Comparative Example 3

[0100] The composition of the ultra-high-strength conductive copper-titanium alloy is, by mass percentage, Ti 4%, Cr 1%, Mg 0.5%, and the balance is copper;

[0101] Preparation method:

[0102] (1) First, Cu is added into a vacuum induction furnace for smelting at a smelting temperature of 1250°C. After melting, Ti is added and stirred thoroughly. Before being discharged from the furnace, Cr and Mg are added into the melt and stirred thoroughly before casting at a casting temperature of 1200°C. The copper-titanium alloy ingot is obtained by milling the surface.

[0103] (2) subjecting the copper-titanium alloy ingot obtained in step (1) to solution treatment at 850° C., holding the temperature for 8 h, and water-cooling at room temperature; and then hot rolling at 700° C., holding the temperature for 3 h, with a processing rate of 60%, to obtain a copper-titanium alloy plate;

[0104] (3) Isothermally aging the copper-titanium alloy plate obtained in step (2) at 450° C. for 100 h to obtain a copper-titanium alloy.

[0105] Figure 6 This is the SEM image of the copper-titanium alloy prepared in Comparative Example 3. Figure 6 It can be seen that after aging at 450℃ for 100h, there is a small amount of precipitation phase centered on the CuTi phase on the grain boundaries in the microstructure, and the main phase is copper matrix.

[0106] The hardness and electrical conductivity of the copper-titanium alloys prepared in Examples 1 to 3 and Comparative Examples 1 to 3 were tested. The test results are shown in Table 1.

[0107] Table 1 Properties of copper-titanium alloys prepared in Examples 1 to 3 and Comparative Examples 1 to 3

[0108]

[0109]

[0110] It can be seen from the above examples that the ultra-high-strength conductive copper-titanium alloy prepared by the preparation method provided by the present invention has high strength and high conductivity, and its hardness can reach 310HV and its conductivity can reach 35%IACS.

[0111] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for preparing an ultra-high-strength conductive copper-titanium alloy, comprising the following steps: (1) melting and casting the raw materials of ultra-high-strength conductive copper-titanium alloy in sequence to obtain a copper-titanium alloy ingot; (2) The copper-titanium alloy ingot obtained in step (1) is subjected to solution treatment, hot rolling and first aging treatment in sequence to obtain a copper-titanium alloy plate; the temperature of the solution treatment is 700-900°C, the holding time of the solution treatment is 4-8 hours, and the cooling method after the solution treatment is room temperature water cooling; the first aging treatment is specifically: first holding at 550-600°C for 1-3 hours, then holding at 500-550°C for 1-3 hours, and finally holding at 400-450°C for 8-12 hours; (3) subjecting the copper-titanium alloy plate obtained in step (2) to a first cold rolling, a second aging treatment, and a second cold rolling in sequence to obtain an ultra-high-strength conductive copper-titanium alloy; the second aging treatment is specifically as follows: first, keeping the temperature at 400-450°C for 1-3 hours, then keeping the temperature at 350-380°C for 1-3 hours, and finally keeping the temperature at 320-350°C for 6-8 hours; Calculated by mass percentage, the ultra-high-strength conductive copper-titanium alloy comprises: Ti 1-5%, Cr 0.1-3%, Mg 0.1-3% and the balance Cu.

2. The preparation method according to claim 1, characterized in that The smelting temperature in step (1) is 1150-1350°C; the casting temperature is 1100-1250°C.

3. The preparation method according to claim 1, characterized in that In the step (2), the hot rolling temperature is 600-850° C., the hot rolling holding time is 1-3 hours, and the hot rolling processing rate is 50-80%.

4. The preparation method according to claim 1, characterized in that The temperatures of the first cold rolling and the second cold rolling in step (3) are independently room temperature.

5. The preparation method according to claim 1 or 4, characterized in that In the step (3), the deformation amounts of the first cold rolling and the second cold rolling are independently 40 to 70%.

6. The ultra-high-strength conductive copper-titanium alloy prepared by the preparation method according to any one of claims 1 to 5.

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