Thermomechanical treatment method for copper-chromium-zirconium alloy strip

Abstract

The invention discloses a thermomechanical treatment method of a copper-chromium-zirconium alloy strip, which comprises the following steps: weighing casting raw materials according to a preset ratio range, and putting the casting raw materials into a smelting furnace for smelting and casting to obtain a cast ingot, the casting raw materials comprising a Cu raw material, a Cr raw material, a Zr raw material and impurities; carrying out heating treatment and hot rolling treatment on the cast ingot to obtain a hot-rolled blank, and carrying out primary solid solution treatment on the hot-rolled blank to obtain a primary solid solution blank; primary cold rolling treatment is carried out on the primary solid solution blank, intermediate heat treatment is carried out on a primary cold-rolled strip, secondary solid solution treatment is carried out on an intermediate strip, and a secondary solid solution blank is obtained; secondary cold rolling treatment is conducted on the secondary solid solution blank, and a secondary cold-rolled strip is obtained; and the secondary cold-rolled strip is subjected to aging treatment, and the copper-chromium-zirconium alloy strip is obtained. By designing the combination of multi-stage solid solution and specific intermediate heat treatment, a precipitated phase is induced to be precipitated in a finer and more dispersed form in the cold rolling process, and the strength and conductivity of the alloy are improved.

Description

Technical Field

[0001] This invention relates to the field of material processing technology, specifically to a deformation heat treatment method for copper-chromium-zirconium alloy strip. Background Technology

[0002] With the rapid development of high-end electronic components towards higher density, miniaturization, and higher reliability, core structural components such as lead frames and connectors are facing increasingly stringent requirements for the comprehensive performance of materials. Copper-chromium-zirconium alloys, possessing excellent high strength, high electrical conductivity, and good heat resistance, have become a key material with great application potential in this field. Their strengthening mechanism mainly relies on the pinning effect of nanoscale precipitates of Cr and Zr elements in the copper matrix, resulting in relative dislocations and grain boundaries, thereby effectively improving the material's strength.

[0003] However, there is an inherent contradiction between the strength and conductivity of copper-chromium-zirconium alloys, a core issue that severely limits their performance ceiling and application scope. Specifically, to obtain high material strength, it is usually necessary to introduce a large number of crystal defects through cold deformation and combine it with aging treatment to promote the dispersed distribution of nano-precipitates. However, these crystal defects and precipitates will have a strong scattering effect on electron transport, resulting in a significant decrease in the material's conductivity. Conversely, to pursue excellent conductivity, it is necessary to eliminate crystal defects through high-temperature annealing to reduce electron scattering, but this will cause grain growth and coarsening of precipitates, resulting in a significant loss of material strength. It is difficult to optimize both simultaneously.

[0004] In existing technologies, the industry commonly uses the conventional process of "solution treatment → cold deformation → aging treatment" to prepare copper-chromium-zirconium alloy strips. However, this process has many insurmountable defects: First, poor performance matching. A single aging treatment is difficult to achieve the optimal quantity, size, and distribution of nano-precipitates. Often, one property must be sacrificed for another. For example, it is difficult to stably achieve the simultaneous satisfaction of tensile strength ≥550MPa and conductivity ≥80% IACS. Second, narrow process window. The control requirements for aging temperature and time are extremely stringent. Slight deviations can easily lead to excessively rapid growth or dissolution of precipitates, resulting in large fluctuations in product performance and low yield. Third, insufficient thermal stability. The alloy microstructure obtained by the conventional process is prone to over-aging during subsequent high-temperature processing or service, leading to material performance degradation.

[0005] In summary, existing technologies, limited by the aforementioned bottlenecks in the processing flow, struggle to effectively and synergistically improve the strength and conductivity of copper-chromium-zirconium alloys. Therefore, a new processing method is urgently needed that can synergistically enhance both the strength and conductivity of copper-chromium-zirconium alloys. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a deformation heat treatment method for copper-chromium-zirconium alloy strips. The aim is to improve the alloy's strength and electrical conductivity by designing a combination of multi-stage solid solution treatment and specific intermediate heat treatment, thereby inducing precipitates to form finer and more dispersed phases during cold rolling.

[0007] This invention discloses a deformation heat treatment method for copper-chromium-zirconium alloy strip, comprising: Weigh the casting raw materials according to the preset ratio range, and put the casting raw materials into the melting furnace for melting and casting to obtain ingots. The casting raw materials include Cu raw materials, Cr raw materials, Zr raw materials and impurities. The ingot is placed in a heating furnace for heating treatment, and the heated ingot is hot rolled to obtain a hot rolled billet. The heating treatment temperature range is 920~980℃, and the holding time of the heating treatment is 1~3 hours. Hot-rolled billets are subjected to primary solution treatment at a temperature range of 700~860℃ to obtain primary solution-treated billets. The primary solution-treated billet is subjected to a first cold rolling process to obtain the first cold-rolled strip; The first cold-rolled strip is subjected to intermediate heat treatment to obtain intermediate strip, and the intermediate strip is subjected to secondary solution treatment to obtain secondary solution billet; The secondary solution-treated billet is subjected to secondary cold rolling to obtain secondary cold-rolled strip; The secondary cold-rolled strip is subjected to aging treatment to obtain copper-chromium-zirconium alloy strip.

[0008] Preferably, the preset proportion range of casting raw materials is as follows: Cu raw material accounts for 98.55~99.45% by mass, Cr raw material accounts for 0.5~1.2% by mass, Zr raw material accounts for 0.05~0.25% by mass, and impurities account for less than or equal to 0.03% by mass.

[0009] Preferably, after placing the ingot in a heating furnace for heat treatment to obtain a hot-rolled billet, the process further includes: The hot-rolled billet is subjected to double-sided milling to remove 0.8~1.2 mm of oxide layer and defect layer from the upper and lower surfaces.

[0010] Preferably, the heat treatment time for the first-stage solution treatment is 2 to 5 minutes; After subjecting the hot-rolled billet to a first-stage solution treatment at a temperature range of 700~860℃ to obtain a first-stage solution-treated billet, the process further includes: The primary solution-treated billet is cooled to a preset temperature using a preset cooling method, which includes one or more of water quenching, air cooling, and oil quenching, with a preset temperature of 20~30℃.

[0011] Preferably, the deformation range of the first cold-rolled strip compared to the first solution-treated billet is 80% to 90%, and the deformation range of the second cold-rolled strip compared to the first solution-treated billet is 50% to 80%.

[0012] Preferably, the first cold-rolled strip is subjected to intermediate heat treatment to obtain intermediate strip, comprising: The first cold-rolled strip is placed in a bell furnace and heated to a preset intermediate heat treatment temperature. After holding at this temperature for 1 to 4 hours, it is cooled to obtain an intermediate strip. The preset intermediate heat treatment temperature is 450 to 550°C.

[0013] Preferably, the treatment temperature for the secondary solution treatment is 800~940℃, and the holding time for the secondary solution treatment is 1~10 minutes; After the secondary solution-treated billet is subjected to secondary cold rolling to obtain secondary cold-rolled strip, the process also includes cooling the secondary cold-rolled strip.

[0014] Preferably, the aging treatment temperature range is 400~480℃, and the aging treatment holding time is 2~6 hours.

[0015] Preferably, the copper-chromium-zirconium alloy strip has a tensile strength greater than or equal to 580 MPa, a conductivity greater than or equal to 82% IACS, and a hardness greater than or equal to 180 HV.

[0016] Preferably, the copper-chromium-zirconium alloy strip includes a Cr-Zr composite precipitate phase with a size of 3~10 nm.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention, through a combination of multi-stage solution treatment and specific intermediate heat treatment, induces the precipitation of precipitates in a finer, more dispersed form during cold rolling, effectively resolving the trade-off between strength and electrical conductivity in copper-chromium-zirconium alloys. The deformation heat treatment method of this invention significantly broadens the process window by rationally designing the process parameters for multi-stage solution treatment, intermediate heat treatment, and cold rolling. In the microstructure of the copper-chromium-zirconium alloy strip obtained by this method, the Cr-Zr composite precipitates are small in size and uniformly distributed. This microstructure significantly reduces the coarsening rate of the precipitates during subsequent high-temperature processing or service, effectively suppressing over-aging and improving the thermal stability of the material. Attached Figure Description

[0018] Figure 1 A schematic flowchart of the deformation heat treatment method for copper-chromium-zirconium alloy strip provided by the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] The present invention will now be described in further detail with reference to the accompanying drawings.

[0021] like Figure 1 As shown in the figure, an embodiment of the present invention provides a processing method for high-strength conductive Cu-Ni-Si alloy strip, including the following steps.

[0022] S1. Weigh the casting raw materials according to the preset ratio range, and put the casting raw materials into the smelting furnace for smelting and casting to obtain ingots.

[0023] In this embodiment of the invention, the casting raw materials include Cu, Cr, Zr, and impurities. The preset proportions are controlled as follows: Cu raw materials account for 98.55% to 99.45% by mass, Cr raw materials account for 0.5% to 1.2% by mass, Zr raw materials account for 0.05% to 0.25% by mass, and impurities account for less than or equal to 0.03% by mass.

[0024] For example, the impurities are mainly common metallic impurities such as Fe, Pb, and Sn, and their content needs to be strictly controlled through raw material screening and refining processes during smelting. For instance, oxygen-free copper is used as the Cu raw material matrix, chromium blocks with a purity of ≥99.95% are selected as the Cr raw material, and intermediate alloys (such as Cu-Zr alloys) with a zirconium content of ≥99.9% are selected as the Zr raw material to avoid introducing too many impurities that would affect the alloy's performance.

[0025] For example, during the smelting process, Cu raw material is first added to a medium-frequency induction melting furnace and heated to 1150~1200℃ to completely melt it. Then, Cr raw material and Zr raw material are added sequentially, and the mixture is continuously stirred for 10~15 minutes to ensure uniform composition. During this period, argon gas is introduced for protection to prevent oxidation of alloying elements. The molten liquid is poured into a casting mold at a temperature of 1180~1220℃. The mold size matches the target ingot. At the same time, the poured molten liquid is cooled by water cooling at a rate controlled at 8~12℃ / s, finally obtaining an ingot with dimensions of 150mm×420mm×6000mm.

[0026] S2. The ingot is placed in a heating furnace for heating treatment, and the heated ingot is hot rolled to obtain a hot-rolled billet.

[0027] In this embodiment of the invention, the temperature range of the heat treatment is 920~980℃, and the holding time of the heat treatment is 1~3 hours. For example, a box-type resistance furnace is used to heat the ingot, heating the ingot from room temperature to 950℃ at a heating rate of 5℃ / min, holding it at that temperature for 2 hours, cooling it to 850℃ in the furnace, and then taking it out of the furnace for hot rolling.

[0028] During the hot rolling process, the initial rolling temperature is controlled at 820~850℃, and the final rolling temperature is not lower than 700℃. The ingot thickness is gradually reduced from 150mm to 15~20mm through multiple rolling passes, and the reduction rate of each pass is controlled at 15~25%. High-pressure water is used to cool the rolls and the surface of the billet during the rolling process to prevent local overheating that could lead to oxidation or abnormal grain growth, and finally obtain a hot-rolled billet with uniform thickness.

[0029] Heat treatment and hot rolling of ingots can effectively eliminate coarse columnar crystals and segregation structures formed during the solidification process, laying a uniform microstructure foundation for subsequent processing.

[0030] Specifically, high-temperature heating treatment at 920~980℃ can promote the full diffusion of element atoms inside the ingot, significantly reducing the degree of compositional segregation; while the deformation of the ingot through multiple passes with large reduction rates during hot rolling can break the original coarse grains into fine equiaxed grains, and at the same time introduce a large number of crystal defects such as dislocations into the grains, providing abundant nucleation sites for the subsequent nucleation of precipitated phases.

[0031] Furthermore, due to the high-temperature rolling process, hot-rolled billets are prone to developing an oxide layer of uneven thickness on their surface, and may also contain internal defects such as micro-cracks and inclusions, which need to be removed by double-sided milling. Double-sided milling is performed on the hot-rolled billets to remove 0.8~1.2 mm of oxide and defect layers from both the upper and lower surfaces.

[0032] For example, the milling process uses a dedicated double-sided milling machine. Before milling, the hot-rolled billet is leveled to ensure that the surface flatness deviation is ≤0.5mm / m. Then, the billet is fed into the milling station, and the upper and lower milling cutters simultaneously mill the upper and lower surfaces of the billet. The milling depth is controlled at 0.8~1.2mm per side, the milling speed is adjusted to 10~15m / min, and the feed rate is 0.1~0.2mm / r. After milling, the milling debris on the surface of the billet is removed by high-pressure air blowing, resulting in a billet with a smooth surface, free of oxide and defect layers, and its thickness is controlled at 8~13mm.

[0033] Double-sided milling can completely remove the oxide scale formed on the surface of hot-rolled billets due to high-temperature oxidation, as well as casting defects such as porosity and inclusions that may exist on the surface of the ingot. This prevents these defects from expanding into cracks during subsequent cold rolling, ensuring the consistency of the billet's surface quality and internal structure.

[0034] S3. The hot-rolled billet is subjected to primary solution treatment at a temperature range of 700~860℃ to obtain primary solution-treated billet.

[0035] In this embodiment of the invention, the milled hot-rolled billet is fed into a continuous solution treatment furnace for primary solution treatment. The furnace temperature is controlled at 700~860℃, and the holding time for primary solution treatment is 2~5 minutes. The specific holding time is adjusted according to the thickness of the billet—for example, a billet with a thickness of 10mm is held for 3 minutes, and a billet with a thickness of 12mm is held for 4 minutes, to ensure that the internal temperature of the billet is uniform.

[0036] After the first-stage solution treatment is completed, the first-stage solution billet is cooled to a preset temperature using a preset cooling method, which includes one or more of water quenching, air cooling, and oil quenching, with a preset temperature of 20~30℃.

[0037] For example, water quenching is used to cool the first-stage solution-treated billet. The cooling medium is deionized water at room temperature (20~30℃), and the water quenching time is controlled to be 3~5 seconds. This allows the billet to be cooled rapidly from the solution temperature to room temperature, preventing the precipitated phase from precipitating prematurely during the cooling process, and finally obtaining the first-stage solution-treated billet.

[0038] S4. The first-stage solution-treated billet is subjected to initial cold rolling to obtain the first-stage cold-rolled strip.

[0039] In this embodiment of the invention, the primary solution billet needs to be cleaned and dried before cold rolling to remove surface water stains and impurities, and then sent to a four-roll cold rolling mill for the first cold rolling. The deformation of the first cold-rolled strip is 80% to 90% compared to the primary solution billet.

[0040] For example, the initial cold rolling adopts multi-pass rolling, with the reduction rate of each pass controlled at 20-30% and the rolling speed at 100-150 m / min. During the rolling process, the bending force of the rolls and the flow rate of rolling oil are adjusted to ensure good strip shape. Finally, the primary solution-treated billet is rolled from 8-13 mm to 1.0-1.5 mm, with a deformation range of 80%-90% (for example, when the initial thickness of the billet is 10 mm and the thickness after rolling is 1.0 mm, the deformation is (10-1.0) / 10×100%=90%), thus obtaining the first cold-rolled strip.

[0041] In this way, a large number of high-density dislocations and grain boundaries are introduced into the strip through cold rolling with large deformation. These crystal defects can not only significantly refine the grain size, but also provide sufficient sites for the nucleation of precipitated phases during subsequent intermediate heat treatment.

[0042] S5. The first cold-rolled strip is subjected to intermediate heat treatment to obtain intermediate strip, and the intermediate strip is subjected to secondary solution treatment to obtain secondary solution billet.

[0043] In this embodiment of the invention, the purpose of intermediate heat treatment is to induce the precipitation of fine Cr-Zr composite phases in the supersaturated solid solution inside the first cold-rolled strip by controlling the temperature and holding time, while eliminating some of the internal stress generated by cold rolling deformation.

[0044] In the process of obtaining intermediate strip by intermediate heat treatment of the first cold-rolled strip, the first cold-rolled strip is placed in a bell furnace and heated to the preset intermediate heat treatment temperature, and then cooled after holding at the temperature for 1 to 4 hours to obtain intermediate strip. The preset intermediate heat treatment temperature is 450 to 550℃.

[0045] Furthermore, when performing secondary solution treatment on the intermediate strip, the treatment temperature is 800~940℃ and the holding time is 1~10 minutes.

[0046] For example, the intermediate strip is fed into a continuous solution furnace and rapidly heated to 880°C at a heating rate of 10°C / s. After holding at that temperature for 5 minutes, it is immediately quenched in water at a rate of 50~80°C / s. This allows the alloying elements that have not been completely precipitated inside the strip to be re-dissolved into a supersaturated solid solution. At the same time, some undissolved fine precipitates are retained as the core for subsequent aging treatment, ultimately yielding a secondary solution billet.

[0047] S6. The secondary solution-treated billet is subjected to secondary cold rolling to obtain secondary cold-rolled strip.

[0048] In this embodiment of the invention, the deformation of the secondary cold-rolled strip is 50% to 80% compared to the primary solution-treated billet.

[0049] For example, the secondary solution-treated billet is fed into a four-roll cold rolling mill and rolled in multiple passes with a small reduction rate. The reduction rate of each pass is controlled at 10-15%, and the rolling speed is 80-120 m / min. The secondary solution-treated billet is further thinned from 1.0-1.5 mm to 0.2-0.6 mm, and the deformation is controlled at 60%-70% (for example, when the initial thickness is 1.2 mm and the thickness after rolling is 0.4 mm, the deformation is (1.2-0.4) / 1.2×100%≈66.7%).

[0050] During the secondary cold rolling process, the subgrains inside the strip are further refined, the dislocation density increases again, and some of the remaining precipitates are broken up, providing more nucleation sites for the uniform distribution of precipitates during the final aging treatment.

[0051] After the second cold rolling, the second cold-rolled strip is cooled, for example, by using air cooling to cool the strip temperature to room temperature, with the cooling rate controlled at 5~10℃ / min, to avoid warping of the strip due to rapid cooling.

[0052] S7. The secondary cold-rolled strip is subjected to aging treatment to obtain copper-chromium-zirconium alloy strip.

[0053] In this embodiment of the invention, the aging treatment temperature range is 400~480℃, the holding time is 2~6 hours, and the secondary cold-rolled strip is subjected to aging treatment to obtain copper-chromium-zirconium alloy strip. The copper-chromium-zirconium alloy strip includes Cr-Zr composite precipitates with a size of 3~10nm.

[0054] For example, the secondary cold-rolled strip is placed in a box-type aging furnace and heated to 450°C at a heating rate of 2°C / min. After holding at that temperature for 4 hours, it is cooled to room temperature with the furnace.

[0055] During this process, Cr and Zr atoms in the supersaturated solid solution will precipitate a large number of Cr-Zr composite precipitates with a size of 3~10nm, with the precipitates remaining from the secondary cold rolling as the core. These precipitates are uniformly distributed in the copper matrix, which significantly improves the strength of the alloy through dispersion strengthening. At the same time, the content of solid solution atoms in the matrix decreases, and the conductivity also increases.

[0056] The final copper-chromium-zirconium alloy strip has a tensile strength greater than or equal to 580 MPa, an electrical conductivity greater than or equal to 82% IACS, and a hardness greater than or equal to 180 HV.

[0057] For example, the strip prepared using the above process parameters has a tensile strength of up to 620 MPa, a conductivity of 85% IACS, and a hardness of 190 HV, which fully meets the requirements of high-strength and high-conductivity copper alloy materials in fields such as high-end electronic components and high-speed train contact networks.

[0058] The following two comparative examples illustrate the deformation heat treatment method for copper-chromium-zirconium alloy strip provided by the present invention, and compare the performance of copper-chromium-zirconium alloy strip prepared by the method provided by the present invention with that prepared by conventional methods.

[0059] Example 1: Preparation of an alloy ingot with the composition of Cu-0.8Cr-0.15Zr.

[0060] After solution treatment at 950℃ for 2 hours, the ingot was hot-rolled to a thickness of 16.5 mm, followed by milling with a single-sided milling amount of 1 mm, resulting in a billet thickness of 14.5 mm. A first-stage solution treatment was performed: holding at 800℃ for 3 minutes, followed by rapid air cooling. Next, a first cold rolling process was executed: the material deformation was controlled at 82.8%, ultimately rolling to the target thickness of 2.5 mm. An intermediate heat treatment was then performed: holding at 500℃ for 2 hours, followed by air cooling. A second-stage solution treatment was then performed: the temperature was raised to 880℃ and held for 5 minutes, followed by air cooling again. A second cold rolling process was then performed: this time the deformation was set at 80%, rolling the material to a final thickness of 0.5 mm. Finally, a final aging treatment was carried out: holding at 450℃ for 4 hours to complete all heat treatment processes.

[0061] Comparative Example 1 (Conventional Process): Using the same ingot as in Example 1, the material was solution-treated at 950°C for 2 hours, followed by hot rolling to a thickness of 10 mm. Subsequently, without intermediate heating, the material was further rolled to a final thickness of 1.5 mm using a cold rolling process, resulting in a total deformation of 85%. Finally, the material underwent aging treatment, specifically holding at 450°C for 4 hours.

[0062] The performance of the strips prepared in Example 1 and Comparative Example 1 were tested respectively, and the results are shown in the table below:

[0063] Data shows that the strip prepared by the process of this invention is significantly superior to the strip prepared by conventional processes in terms of three key performance indicators: tensile strength, conductivity, and hardness. Specifically, the tensile strength of Example 1 is increased by approximately 10.2%, the conductivity is increased by 2.4%, and the hardness is increased by 12.1% compared to Comparative Example 1.

[0064] The core reason for this performance difference lies in the multi-stage deformation heat treatment process employed in this invention: "first-stage solution treatment - first cold rolling - intermediate heat treatment - second-stage solution treatment - second cold rolling - aging." Through the alternating combination of two solution treatments and two cold rollings, fine Cr-Zr composite phase nuclei are pre-precipitated during the intermediate heat treatment stage. The second cold rolling further refines the grains and increases dislocation density. Finally, during aging, a large number of 3-10 nm dispersed precipitates are uniformly distributed, fully leveraging the synergistic effect of deformation strengthening and dispersion strengthening. In contrast, Comparative Example 1 only uses a single solution treatment and large-deformation cold rolling. The grain refinement effect during cold rolling is limited, and there are insufficient nucleation sites for precipitates during aging, resulting in larger and unevenly distributed precipitates and a weaker strengthening effect. Particularly noteworthy is the pre-precipitation behavior induced by the intermediate heat treatment at 500℃ for 2 hours in Example 1. As can be seen from the above technical solution, this application provides a deformation heat treatment method for copper-chromium-zirconium alloy strip, comprising: weighing casting raw materials according to a preset proportion range, and feeding the casting raw materials into a melting furnace for melting and casting to obtain an ingot, wherein the casting raw materials include Cu raw materials, Cr raw materials, Zr raw materials and impurities; heating the ingot to obtain a hot-rolled billet, and subjecting the hot-rolled billet to a first-stage solution treatment to obtain a first-stage solution billet; subjecting the first-stage solution billet to a first-stage cold rolling treatment, subjecting the first-stage cold-rolled strip to an intermediate heat treatment to obtain an intermediate strip, and subjecting the intermediate strip to a second-stage solution treatment to obtain a second-stage solution billet; subjecting the second-stage solution billet to a second-stage cold rolling treatment to obtain a second-stage cold-rolled strip; and subjecting the second-stage cold-rolled strip to an aging treatment to obtain a copper-chromium-zirconium alloy strip. This invention, by designing a combination of multi-stage solution treatment and specific intermediate heat treatment, induces precipitates to form finer and more dispersed phases during cold rolling, thereby improving the alloy's strength and electrical conductivity.

[0065] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A deformation heat treatment method for copper-chromium-zirconium alloy strip, characterized in that, include: Weigh the casting raw materials according to the preset proportion range, and put the casting raw materials into the melting furnace for melting and casting to obtain ingots. The casting raw materials include Cu raw materials, Cr raw materials, Zr raw materials and impurities. The ingot is placed in a heating furnace for heating treatment, and the heated ingot is hot rolled to obtain a hot rolled billet. The temperature range of the heating treatment is 920~980℃, and the holding time of the heating treatment is 1~3 hours. The hot-rolled billet is subjected to a first-stage solution treatment at a temperature range of 700~860℃ to obtain a first-stage solution-treated billet. The primary solution-treated billet is subjected to a first cold rolling process to obtain a first cold-rolled strip; The first cold-rolled strip is subjected to intermediate heat treatment to obtain intermediate strip, and the intermediate strip is subjected to secondary solution treatment to obtain secondary solution billet; The secondary solution-treated billet is subjected to a secondary cold rolling process to obtain a secondary cold-rolled strip; The secondary cold-rolled strip is subjected to aging treatment to obtain copper-chromium-zirconium alloy strip.

2. The deformation heat treatment method for copper-chromium-zirconium alloy strip according to claim 1, characterized in that, The preset proportion range of the casting raw materials is as follows: the mass percentage of Cu raw material is 98.55~99.45%, the mass percentage of Cr raw material is 0.5~1.2%, the mass percentage of Zr raw material is 0.05~0.25%, and the mass percentage of impurities is less than or equal to 0.03%.

3. The deformation heat treatment method for copper-chromium-zirconium alloy strip according to claim 1, characterized in that, After placing the ingot in a heating furnace for heating treatment to obtain a hot-rolled billet, the process further includes: The hot-rolled billet is subjected to double-sided milling to remove 0.8~1.2 mm of oxide layer and defect layer from the upper and lower surfaces.

4. The deformation heat treatment method for copper-chromium-zirconium alloy strip according to claim 1 or 3, characterized in that, The heat preservation time for the first-stage solution treatment is 2-5 minutes; After subjecting the hot-rolled billet to a first-stage solution treatment at a temperature range of 700~860℃ to obtain a first-stage solution-treated billet, the process further includes: The primary solution-treated billet is cooled to a preset temperature using a preset cooling method, which includes one or more of water quenching, air cooling, and oil quenching, and the preset temperature is 20~30℃.

5. The deformation heat treatment method for copper-chromium-zirconium alloy strip according to claim 1, characterized in that, The deformation range of the first cold-rolled strip compared to the first-stage solution-treated billet is 80% to 90%, and the deformation range of the second cold-rolled strip compared to the first-stage solution-treated billet is 50% to 80%.

6. The deformation heat treatment method for copper-chromium-zirconium alloy strip according to claim 1, characterized in that, The intermediate heat treatment of the first cold-rolled strip to obtain intermediate strip includes: The first cold-rolled strip is placed in a bell furnace and heated to a preset intermediate heat treatment temperature. After holding at this temperature for 1 to 4 hours, it is cooled to obtain the intermediate strip. The preset intermediate heat treatment temperature is 450 to 550°C.

7. The deformation heat treatment method for copper-chromium-zirconium alloy strip according to claim 1, characterized in that, The secondary solution treatment temperature is 800~940℃, and the holding time for the secondary solution treatment is 1~10 minutes; After the secondary solution-treated billet is subjected to secondary cold rolling to obtain secondary cold-rolled strip, the process further includes cooling the secondary cold-rolled strip.

8. The deformation heat treatment method for copper-chromium-zirconium alloy strip according to claim 1, characterized in that, The aging treatment temperature range is 400~480℃, and the aging treatment holding time is 2~6 hours.

9. The deformation heat treatment method for copper-chromium-zirconium alloy strip according to claim 1, characterized in that, The copper-chromium-zirconium alloy strip has a tensile strength greater than or equal to 580 MPa, a conductivity greater than or equal to 82% IACS, and a hardness greater than or equal to 180 HV.

10. The deformation heat treatment method for copper-chromium-zirconium alloy strip according to claim 1, characterized in that, The copper-chromium-zirconium alloy strip includes a Cr-Zr composite precipitate phase, the size of which is 3~10 nm.

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