Balanced copper-cobalt-nickel-phosphorus alloy strip and preparation method thereof

Abstract

The invention provides a balanced copper-cobalt-nickel-phosphorus alloy strip and a preparation method thereof, and relates to the technical field of copper alloys. The balanced copper-cobalt-nickel-phosphorus alloy strip provided by the invention comprises the following components in percentage by mass: 0.1 to 0.5 percent of Co, 0.1 to 0.5 percent of Ni, 0.1 to 0.3 percent of P, 0.05 to 0.2 percent of Cr and the balance of Cu. The tensile strength of the alloy strip ranges from 700 MPa to 770 MPa, the percentage elongation after fracture A50 is larger than or equal to 3%, the hardness HV ranges from 200 to 250, the electric conductivity is larger than or equal to 70% IACS, the grain size is smaller than or equal to 0.015 mm, the requirements that 90-degree bending R / T is smaller than or equal to 1.0 and 180-degree bending R / T is smaller than or equal to 1.5 in the GW / BW direction can be met, and the requirements of the high-end field can be met.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of copper alloy, in particular to a balanced copper-cobalt-nickel-phosphorus alloy strip and a preparation method thereof. BACKGROUND

[0002] In today's era of rapid development of science and technology, strategic emerging industries such as electronic information, aerospace, and new energy vehicles are showing a vigorous development trend, and the performance requirements for materials are becoming increasingly stringent. Copper alloy, with its excellent electrical conductivity, occupies an irreplaceable position in many fields such as electrical connection and electronic heat dissipation. However, traditional copper alloys often struggle to achieve an ideal balance between strength and electrical conductivity, making it difficult to meet the high requirements of high-end fields for comprehensive material performance. For example, in the field of electronic information, as integrated circuits develop towards high integration and miniaturization, lead frames and other key components need to have higher strength to withstand complex processing and harsh working environments, while also maintaining good electrical conductivity to ensure fast signal transmission. In the field of aerospace, the lightweight and high performance of aircraft have put forward extremely high requirements for the strength and electrical conductivity of conductive structural materials to reduce weight and improve energy efficiency. In the field of new energy vehicles, key components such as motors and batteries require high-strength and high-conductivity copper alloy materials to improve energy conversion efficiency and reliability.

[0003] In view of the above, the present application is proposed. SUMMARY

[0004] The first object of the present application is to provide a balanced copper-cobalt-nickel-phosphorus alloy strip to solve the problem of the difficulty in balancing the strength and electrical conductivity of traditional copper alloys.

[0005] The second object of the present application is to provide a preparation method for the above-mentioned balanced copper-cobalt-nickel-phosphorus alloy strip.

[0006] In order to achieve the above objects, the following technical solutions are adopted: In a first aspect, the present application provides a balanced copper-cobalt-nickel-phosphorus alloy strip, which comprises, by mass percentage: Co 0.1% to 0.5%, Ni 0.1% to 0.5%, P 0.1% to 0.3%, Cr 0.05% to 0.2%, and the balance being Cu.

[0007] As a further technical solution, it also includes one or more of Mg, Zn, Fe, Si, Mn, Ti, Zr, Al, or Pb with a mass percentage of 0.1% to 0.8%.

[0008] In a second aspect, the present application provides a preparation method for the above-mentioned balanced copper-cobalt-nickel-phosphorus alloy strip, comprising the following steps: According to the mass percentage, then sequentially smelting, casting, hot rolling, milling, on-line solid solution, first annealing, first cold rolling, second annealing, second cold rolling, third annealing, third cold rolling and fourth annealing, a copper-nickel-tin alloy strip is prepared.

[0009] As a further technical solution, the smelting temperature is 1220-1240℃.

[0010] As a further technical solution, the casting temperature is 1210-1230℃, and the casting speed is 55-85mm / min.

[0011] As a further technical solution, the cast ingot is heated to 840-930℃, and after holding for 6-8h, hot rolling is performed at a temperature of 820-910℃. The total rolling rate of the hot rolling is 90%-95%, and the final rolling temperature is 650-750℃.

[0012] As a further technical solution, the on-line solid solution is performed in a vertical continuous annealing furnace, the on-line solid solution temperature is 900-1000℃, and the speed is 20-30m / min.

[0013] As a further technical solution, the first annealing is continuous annealing, the continuous annealing temperature is 600-700℃, and the continuous annealing speed is 25-40m / min.

[0014] As a further technical solution, the total rolling rate of the first cold rolling is 80%-85%; The total rolling rate of the second cold rolling is 40%-70%; The total rolling rate of the third cold rolling is 40%-70%.

[0015] As a further technical solution, the second annealing is bell jar annealing, the bell jar annealing temperature is 370-430℃, the holding time is 4-6h, and the annealing atmosphere is a mixed atmosphere of reducing gas and inert gas; The third annealing is bell jar annealing, the bell jar annealing temperature is 350-410℃, the holding time is 4-6h, and the annealing atmosphere is a mixed atmosphere of reducing gas and inert gas; The fourth annealing is bell jar annealing, the bell jar annealing temperature is 270-330℃, the holding time is 2-4h, and the annealing atmosphere is a mixed atmosphere of reducing gas and inert gas.

[0016] Compared with the prior art, the present application has the following beneficial effects: The balanced copper-cobalt-nickel-phosphorus alloy strip provided by the application is compounded with Co, Ni, P, Cr, Mg and other alloy elements, wherein Co generates fine and dispersed precipitated phases in the matrix, can synergistically strengthen Cr and Ni, forms multiple precipitated phases, hinders the movement of dislocations and grain boundaries, thereby refining the grains and improving the strength of the alloy; P and Ni synergistically promote the precipitation of Ni elements from the matrix; in the melting and casting process, P has a deoxidizing effect, can increase the fluidity of the melt and reduce the ingot defects; Cr elements mainly provide precipitation strengthening effect, and Cr elements can be segregated at the grain boundaries to stabilize the grain boundaries and inhibit grain coarsening during aging process. The balanced copper-cobalt-nickel-phosphorus alloy strip has a tensile strength of 700-770 MPa, an elongation A 50 ≥ 3%, a hardness HV200-250, an electrical conductivity ≥ 70% IACS, a grain size ≤ 0.015 mm, and meets 90° bending R / T ≤ 1.0 and 180° bending R / T ≤ 1.5 in the GW / BW direction to meet the needs of high-end fields. DETAILED DESCRIPTION

[0017] The embodiments of the application will be described in detail below with reference to the embodiments and examples, but those skilled in the art will understand that the following embodiments and examples are only used to illustrate the application and should not be regarded as limiting the scope of the application. All other examples obtained by those skilled in the art without creative labor based on the examples in the application belong to the scope of protection of the application. If the specific conditions are not specified, the conventional conditions or the conditions recommended by the manufacturer are used. If the reagents or instruments used are not specified by the manufacturer, they are all conventional products that can be purchased on the market.

[0018] In a first aspect, the application provides a balanced copper-cobalt-nickel-phosphorus alloy strip mainly composed of Co, Ni, P, Cr and Cu. For example, the mass fraction of Co can be, but is not limited to, 0.1%, 0.2% or 0.5%; the mass fraction of Ni can be, but is not limited to, 0.1%, 0.3% or 0.5%; the mass fraction of P can be, but is not limited to, 0.1%, 0.2% or 0.3%; and the mass fraction of Cr can be, but is not limited to, 0.05%, 0.1% or 0.2%.

[0019] Co can be solid-solved in the matrix, causing lattice distortion and improving the strength of the alloy. In addition, Co elements can form Co-P phases with P elements. The moving dislocations will be pinned by the second phase after encountering the dispersedly distributed second phase, further improving the strength of the alloy. If the content of Co is too low, the solid-solution strengthening effect is not significant, and excessive addition of Co will reduce the electrical conductivity of the alloy and produce coarse Co-rich phases.

[0020] Ni and Cu have similar atomic radii, so Ni will occupy Cu atomic positions and can form solid solutions in any proportion, increasing the alloy's strength. Furthermore, Ni and P can form Ni... x P y The precipitated second-phase particles are dispersed in the matrix, effectively hindering dislocation slip and refining the grain size. Insufficient Ni content results in insignificant strengthening and insufficient Ni to bond with P, leading to P excess and decreased alloy conductivity. Excessive Ni content, on the other hand, easily forms coarse second-phase particles, affecting the material's mechanical properties and reducing conductivity.

[0021] P can form Co with Co and Ni. x P y Ni x P y Precipitated phases hinder dislocation and grain boundary movement, refine grains, and improve alloy strength. In addition, phosphorus (P) acts as a degassing agent and increases melt fluidity. Too low a P content prevents the formation of sufficient precipitates, while too high a content negatively impacts conductivity and can easily lead to hot-rolling cracking.

[0022] During the casting process, Cr preferentially precipitates at grain boundaries, thus achieving grain boundary strengthening and reducing cracking during hot rolling. In addition, Cr can improve the corrosion resistance of copper alloys. Cr has low solid solubility in copper alloys, and during aging, it will produce fine precipitates that improve the alloy strength. If the Cr content is too low, the strengthening effect will be insufficient; if the Cr content is too high, Cr will lead to the formation of coarse second phases.

[0023] Traditional high-strength and high-conductivity alloys such as Cu-Fe, Cu-Cr, and Cu-Ni alloys are difficult to meet the comprehensive performance requirements of strength ≥700MPa and conductivity ≥70%IACS. To address the shortcomings of existing technologies, this invention improves a novel copper-cobalt-nickel-phosphorus alloy system. By rationally controlling the content of each element and adding multiple alloying elements such as Co, Ni, P, Cr, and Mg, a synergistic improvement in strength (≥700MPa) and conductivity (≥70%IACS) is achieved, making it an ideal material to meet the needs of high-end fields.

[0024] In some optional embodiments, it also includes one or more of Mg, Zn, Fe, Si, Mn, Ti, Zr, Al or Pb in a mass percentage of 0.1% to 0.8%.

[0025] The addition of small amounts of Mg, Zn, Fe, Si, Mn, Ti, Zr, Al, and Pb can refine the grain size and improve the mechanical properties of the material. Excessive addition will reduce the alloy's electrical conductivity, while insufficient addition will have little strengthening effect. Si can form Ni with Ni and Co. x Si y Co xSi y These precipitates hinder dislocation and grain boundary movement, refine grains, and improve alloy strength. Mg and Ti contribute to improving the alloy's bending properties.

[0026] In some optional embodiments, the thickness of the balanced copper-cobalt-nickel-phosphorus alloy strip is 0.1~0.4mm and the width is ≥580mm.

[0027] Secondly, the present invention provides a method for preparing the above-mentioned balanced copper-cobalt-nickel-phosphorus alloy strip, comprising the following steps: The raw materials are batched according to the mass percentage, and then smelting, casting, hot rolling, milling, online solution treatment, first annealing, first cold rolling, second annealing, second cold rolling, third annealing, third cold rolling, and fourth annealing are carried out in sequence to prepare copper-nickel-tin alloy strip.

[0028] This invention employs a combined process of "online solution treatment + pre-aging + multi-stage deformation heat treatment + aging". The online solution treatment eliminates enriched phases such as Co, P, and Cr, allowing them to fully dissolve into the matrix. A brief pre-aging process then further precipitates easily precipitated elements such as Co, Ni, P, and Cr, resulting in the formation of Co... x P y Ni x P y The fine dispersed phases, which hinder dislocation slip during subsequent cold deformation, promote grain refinement and dislocation multiplication, and reduce the phase transformation activation energy. During the subsequent annealing process, the fine dispersed phases generated by pre-aging prevent grain growth by delaying grain boundary migration and dislocation movement. A multi-stage deformation heat treatment process is then applied to improve the overall properties of the alloy.

[0029] In some alternative embodiments, the melting temperature may be, for example, but not limited to, 1220°C, 1230°C, or 1240°C.

[0030] In some optional embodiments, the casting temperature may be, for example, but not limited to, 1210°C, 1220°C, or 1230°C; the initial casting speed may be 60±5 mm / min; the normal casting speed may be 80±5 mm / min; and the cooling water flow rate may be 35~45 m³ / min. 3 / h.

[0031] In some alternative embodiments, the cast ingot is heated to 840~930°C, held at that temperature for 6-8 hours, and then hot-rolled at 820~910°C. The total processing rate of the hot rolling can be, for example, but not limited to, 90%, 93%, or 95%, and the final rolling temperature can be, for example, but not limited to, 650°C, 700°C, or 750°C. Water cooling spray is used after hot rolling.

[0032] In some alternative implementations, oxidation inevitably occurs on the surface of the alloy sheet during hot rolling, so double-sided milling is used to remove oxides, with each side milled by 0.7~0.9 mm. In some optional embodiments, the online solution treatment is carried out in a vertical continuous annealing furnace, and the temperature of the online solution treatment can be, for example, but not limited to, 900°C, 950°C or 1000°C, and the speed can be, for example, but not limited to, 20 m / min, 25 m / min or 30 m / min.

[0033] In some optional embodiments, the first annealing is continuous annealing (pre-aging), and the continuous annealing temperature can be, for example, but not limited to, 600°C, 650°C or 700°C, and the continuous annealing speed can be, for example, but not limited to, 25 m / min, 30 m / min or 40 m / min.

[0034] In some alternative implementations, the total processing rate of the first cold rolling can be, for example, but not limited to, 80%, 83%, or 85%, and the number of rolling passes can be, for example, but not limited to, 7, 8, or 9.

[0035] In some alternative implementations, the total processing rate of the second cold rolling can be, for example, but not limited to, 40%, 50% or 70%, and the number of rolling passes can be, for example, but not limited to, 5, 6 or 7.

[0036] In some alternative implementations, the total processing rate of the third cold rolling can be, for example, but not limited to, 40%, 50% or 70%, and the number of rolling passes can be, for example, but not limited to, 5, 6 or 7.

[0037] In some optional embodiments, the second annealing is bell annealing, which is carried out in a bell annealing furnace with a heating time of 4 hours, a temperature of 370~430℃, a holding time of 4~6 hours, and an atmosphere of 75%H2+25%N2. The cooling method is furnace cooling.

[0038] In some optional embodiments, the third annealing is bell annealing, which is carried out in a bell annealing furnace with a heating time of 4 hours, a temperature of 350~410℃, a holding time of 4~6 hours, and an atmosphere of 75%H2+25%N2. The cooling method is furnace cooling.

[0039] In some optional embodiments, the fourth annealing is bell annealing, which is carried out in a bell annealing furnace with a heating time of 3 hours, a temperature of 300°C, a holding time of 2 to 4 hours, and an atmosphere of 75% H2 + 25% N2. The cooling method is furnace cooling.

[0040] The present invention will be further illustrated below with specific embodiments and comparative examples. However, it should be understood that these embodiments are merely for the purpose of more detailed illustration and should not be construed as limiting the present invention in any way.

[0041] Example 1: A balanced copper-cobalt-nickel-phosphorus alloy material, the elemental composition of which is shown in Table 1, by mass percentage includes Co: 0.1%, Ni: 0.1%, P: 0.1%, Cr: 0.05%, Mg: 0.1%, with the balance being copper and unavoidable impurities.

[0042] The preparation method is as follows: a. Weigh the raw materials according to the alloy composition ratio, mix them, and then feed, melt and cast them in sequence; b. Hot rolling; c. Milling; d. Solution treatment; e. Continuous annealing; f. First cold rolling; g. First bell annealing; h. Second cold rolling; i. Second bell annealing; j. Third cold rolling; k. Third bell annealing.

[0043] In step a, a non-vacuum medium-frequency induction furnace is used for melting and casting. Electrolytic copper, pure cobalt, nickel plate, pure chromium, copper-magnesium master alloy, and copper-phosphorus master alloy are added to the furnace. The temperature is raised to 1220~1240℃. After the melt is completely melted, it is poured into a holding furnace and stirred evenly. The casting temperature is controlled at 1210~1230℃. After holding at this temperature for 10 minutes, the casting is poured. The initial casting speed is 60±5mm / min, the normal casting speed is 80±5mm / min, and the normal cooling water flow rate is 35~45m³ / min. 3 / h.

[0044] In step b, the above alloy ingot is heated in a walking beam furnace at a temperature of 840°C for 8 hours. It is then hot-worked at 820°C with a total processing rate of 95%. The final rolling temperature is 650°C, followed by water-cooled spraying.

[0045] In step d, the milled strip is placed in a vertical continuous annealing furnace for solution treatment at a temperature of 950°C and a speed of 30 m / min.

[0046] In step e, the solution-treated strip is placed in a vertical continuous annealing furnace for continuous annealing at a temperature of 600°C and a speed of 25 m / min.

[0047] In step f, the continuously annealed strip is cold rolled once, with a rolling rate of 80%, and goes through 7 passes.

[0048] In step g, the alloy strip after cold rolling is placed in a bell-type annealing furnace for bell annealing. The heating time is 4 hours, the temperature is 370℃, the holding time is 6 hours, and the annealing is carried out in a 75% H2 + 25% N2 atmosphere. The cooling method is furnace cooling.

[0049] In step h, the strip after the first bell annealing is subjected to a second cold rolling process with a rolling rate of 60% and 6 passes.

[0050] In step i, the alloy strip after secondary cold rolling is placed in a bell-type annealing furnace for secondary bell annealing. The heating time is 4 hours, the temperature is 350℃, the holding time is 6 hours, and the annealing is carried out in a 75% H2 + 25% N2 atmosphere. The cooling method is furnace cooling.

[0051] In step j, the strip after secondary bell annealing is subjected to three cold rolling processes with a rolling rate of 40% and five passes.

[0052] In step k, the alloy strip after three cold rollings is placed in a bell-type annealing furnace for three bell-type annealings. The heating time is 3 hours, the temperature is 300℃, the holding time is 2 hours, and the annealing is carried out in a 75% H2 + 25% N2 atmosphere. The cooling method is furnace cooling.

[0053] Example 2: A balanced copper-cobalt-nickel-phosphorus alloy material, the elemental composition of which is shown in Table 1, by mass percentage, includes Co: 0.2%, Ni: 0.2%, P: 0.15%, Cr: 0.1%, Mg: 0.1%, Zn: 0.1%, Fe: 0.1%, with the balance being copper and unavoidable impurities.

[0054] The preparation method is as follows: a. Weigh the raw materials according to the alloy composition ratio, mix them, and then feed, melt and cast them in sequence; b. Hot rolling; c. Milling; d. Solution treatment; e. Continuous annealing; f. First cold rolling; g. First bell annealing; h. Second cold rolling; i. Second bell annealing; j. Third cold rolling; k. Third bell annealing.

[0055] In step a, a non-vacuum medium-frequency induction furnace is used for melting and casting. Electrolytic copper, pure cobalt, nickel plate, pure chromium, pure zinc, copper-magnesium master alloy, copper-iron master alloy, and copper-phosphorus master alloy are added to the furnace. The temperature is raised to 1220~1240℃. After the melt is completely melted, it is poured into a holding furnace and stirred evenly. The casting temperature is controlled at 1210~1230℃. After holding at this temperature for 10 minutes, the casting is poured. The initial casting speed is 60±5mm / min, the normal casting speed is 80±5mm / min, and the normal cooling water flow rate is 35~45m³ / min. 3 / h.

[0056] In step b, the above alloy ingot is heated in a walking beam furnace at a temperature of 890°C for 7 hours, and then hot-deformed at 860°C with a total processing rate of 95%. The final rolling temperature is 690°C, followed by water-cooled spraying.

[0057] In step d, the milled strip is placed in a vertical continuous annealing furnace for solution treatment at a temperature of 950°C and a speed of 20 m / min.

[0058] In step e, the solution-treated strip is placed in a vertical continuous annealing furnace for continuous annealing at a temperature of 650°C and a speed of 30 m / min.

[0059] In step f, the continuously annealed strip is cold rolled once, with a rolling rate of 85%, and goes through 7 passes.

[0060] In step g, the alloy strip after cold rolling is placed in a bell-type annealing furnace for bell annealing. The heating time is 4 hours, the temperature is 390℃, the holding time is 5 hours, and the annealing is carried out in a 75% H2 + 25% N2 atmosphere. The cooling method is furnace cooling.

[0061] In step h, the strip after the first bell annealing is subjected to a second cold rolling process with a rolling rate of 70% and 6 passes.

[0062] In step i, the alloy strip after secondary cold rolling is placed in a bell-type annealing furnace for secondary bell annealing. The heating time is 4 hours, the temperature is 380℃, the holding time is 5 hours, and the annealing is carried out in a 75% H2 + 25% N2 atmosphere. The cooling method is furnace cooling.

[0063] In step j, the strip after secondary bell annealing is subjected to three cold rolling processes with a rolling rate of 70% and five passes.

[0064] In step k, the alloy strip after three cold rollings is placed in a bell-type annealing furnace for three bell-type annealings. The heating time is 2 hours, the temperature is 300℃, the holding time is 4 hours, and the annealing is carried out in a 75% H2 + 25% N2 atmosphere. The cooling method is furnace cooling.

[0065] Example 3: A balanced copper-cobalt-nickel-phosphorus alloy material, the elemental composition of which is shown in Table 1, by mass percentage includes Co: 0.3%, Ni: 0.3%, P: 0.2%, Cr: 0.15%, Si: 0.2%, Ti: 0.3%, Zr: 0.1%, with the balance being copper and unavoidable impurities.

[0066] The preparation method is as follows: a. Weigh the raw materials according to the alloy composition ratio, mix them, and then feed, melt and cast them in sequence; b. Hot rolling; c. Milling; d. Solution treatment; e. Continuous annealing; f. First cold rolling; g. First bell annealing; h. Second cold rolling; i. Second bell annealing; j. Third cold rolling; k. Third bell annealing.

[0067] In step a, a non-vacuum medium-frequency induction furnace is used for melting and casting. Electrolytic copper, pure cobalt, nickel plate, pure chromium, pure zirconium, copper-silicon master alloy, and sponge titanium are added to the furnace. The temperature is raised to 1220~1240℃. After the melt is completely melted, it is poured into a holding furnace and stirred evenly. The casting temperature is controlled at 1210~1230℃. After holding at this temperature for 10 minutes, the casting is poured. The initial casting speed is 60±5mm / min, the normal casting speed is 80±5mm / min, and the normal cooling water flow rate is 35~45m³ / min. 3 / h.

[0068] In step b, the above alloy ingot is heated in a walking beam furnace at a temperature of 930°C for 6 hours, and then hot-deformed at 910°C with a total processing rate of 90%. The final rolling temperature is 750°C, followed by water-cooled spraying.

[0069] In step d, the milled strip is placed in a vertical continuous annealing furnace for solution treatment at a temperature of 950°C and a speed of 30 m / min.

[0070] In step e, the solution-treated strip is placed in a vertical continuous annealing furnace for continuous annealing at a temperature of 700°C and a speed of 40 m / min.

[0071] In step f, the continuously annealed strip is cold rolled once, with a rolling rate of 80%, and goes through 7 passes.

[0072] In step g, the alloy strip after cold rolling is placed in a bell-type annealing furnace for bell annealing. The heating time is 4 hours, the temperature is 430℃, the holding time is 4 hours, and the annealing is carried out in a 75% H2 + 25% N2 atmosphere. The cooling method is furnace cooling.

[0073] In step h, the strip after the first bell annealing is subjected to a second cold rolling process with a rolling rate of 50% and 5 passes.

[0074] In step i, the alloy strip after secondary cold rolling is placed in a bell-type annealing furnace for secondary bell annealing. The heating time is 4 hours, the temperature is 410℃, the holding time is 4 hours, and the annealing is carried out in a 75% H2 + 25% N2 atmosphere. The cooling method is furnace cooling.

[0075] In step j, the strip after secondary bell annealing is subjected to three cold rolling processes with a rolling rate of 40% and five passes.

[0076] In step k, the alloy strip after three cold rollings is placed in a bell-type annealing furnace for three bell-type annealings. The heating time is 3 hours, the temperature is 300℃, the holding time is 4 hours, and the annealing is carried out in a 75% H2 + 25% N2 atmosphere. The cooling method is furnace cooling.

[0077] Example 4 The difference from Example 1 is that the elemental composition is different, as shown in Table 1.

[0078] Example 5 The difference from Example 1 is that the elemental composition is different, as shown in Table 1.

[0079] Example 6 The difference from Example 5 is that the elemental composition is different and no Mg, Zn, Fe, Si, Mn, Ti, Zr, Al, or Pb elements were added. The elemental composition is shown in Table 1.

[0080] Example 7 The difference from Example 1 lies in the elemental composition, which is shown in Table 1.

[0081] Comparative Example 1: The difference from Example 1 is that the content of Co is too low.

[0082] Comparative Example 2: The difference from Example 1 is that the Ni content is too low.

[0083] Comparative Example 3: The difference from Example 1 is that the content of P is too low.

[0084] Comparative Example 4: The difference from Example 1 is that the Cr content is too low.

[0085] Comparative Example 5: The difference from Example 5 is that the content of Co is excessive.

[0086] Comparative Example 6: The difference from Example 5 is that the Ni content is excessive.

[0087] Comparative Example 7: The difference from Example 5 is that the content of P is excessive.

[0088] Comparative Example 8: The difference from Example 5 is that the Cr content is excessive.

[0089] Comparative Example 9: The difference from Example 5 is that the amount of Mg, Zn, Fe, Si, Mn, Ti, Zr, Al, and Pb added is greater than 0.8%.

[0090] Comparative Example 10: The difference from Example 1 is that continuous annealing (pre-aging) was not performed after solution treatment.

[0091] Table 1 Alloy composition formulations of the examples and comparative examples

[0092] Table 2 Performance test results of the examples and comparative examples

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A balanced copper-cobalt-nickel-phosphorus alloy strip, characterized in that, By mass percentage, it includes: Co 0.1%~0.5%, Ni 0.1%~0.5%, P 0.1%~0.3%, Cr 0.05%~0.2%, with the balance being Cu.

2. The balanced copper-cobalt-nickel-phosphorus alloy strip according to claim 1, characterized in that, It also includes one or more of Mg, Zn, Fe, Si, Mn, Ti, Zr, Al or Pb in a mass ratio of 0.1% to 0.8%.

3. The method for preparing the balanced copper-cobalt-nickel-phosphorus alloy strip according to claim 1 or 2, characterized in that, Includes the following steps: The raw materials are batched according to the mass percentage, and then smelting, casting, hot rolling, milling, online solution treatment, first annealing, first cold rolling, second annealing, second cold rolling, third annealing, third cold rolling, and fourth annealing are carried out in sequence to prepare copper-nickel-tin alloy strip.

4. The preparation method according to claim 3, characterized in that, The melting temperature is 1220~1240℃.

5. The preparation method according to claim 3, characterized in that, The casting temperature is 1210~1230℃, and the casting speed is 55~85mm / min.

6. The preparation method according to claim 3, characterized in that, The cast ingot is heated to 840~930℃, held for 6-8 hours, and then hot rolled at 820~910℃. The total processing rate of the hot rolling is 90%~95%, and the final rolling temperature is 650-750℃.

7. The preparation method according to claim 3, characterized in that, The online solution treatment is carried out in a vertical continuous annealing furnace at a temperature of 900-1000℃ and a speed of 20-30m / min.

8. The preparation method according to claim 3, characterized in that, The first annealing is a continuous annealing, with a temperature of 600~700℃ and a speed of 25-40m / min.

9. The preparation method according to claim 3, characterized in that, The total processing rate of the first cold rolling is 80%~85%; The total processing rate of the second cold rolling is 40%~70%; The total processing rate of the third cold rolling is 40% to 70%.

10. The preparation method according to claim 3, characterized in that, The second annealing is bell annealing, with a temperature of 370~430℃, a holding time of 4~6h, and an annealing atmosphere of a mixture of reducing gas and inert gas. The third annealing is bell annealing, with a temperature of 350~410℃, a holding time of 4~6h, and an annealing atmosphere of a mixture of reducing gas and inert gas. The fourth annealing is bell annealing, with a temperature of 270~330℃, a holding time of 2~4h, and an annealing atmosphere of a mixture of reducing gas and inert gas.

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