Pulse electric field cooperated vacuum annealing method for eliminating stress of ultrathin wide titanium foil

Abstract

The invention discloses a pulsed electric field and vacuum annealing cooperation method for eliminating the stress of an ultrathin wide titanium foil, and belongs to the technical field of advanced material manufacturing. Comprising the following steps that S1, the precise titanium foil is cleaned and blow-dried, and residual dirt on the surface is removed to ensure that the belt surface is smooth and clean; s2, pulse current is applied to the titanium foil in the step 1 according to preset process conditions and parameters, and pulsed electric field synergistic stress relief annealing is carried out; and S3, the titanium foil in the step 2 is subjected to stress relief under the action of a pulsed electric field and cooled to the room temperature, and the finished micron-sized titanium foil is obtained. According to the method, dislocation slippage and atom movement of the titanium foil are promoted through the heat effect and the impact effect generated by the synergistic effect of the pulsed electric field and the vacuum annealing; the residual stress of the treated titanium foil is effectively removed, the deformation and warping degree of the material is remarkably reduced, the oxidation phenomenon is avoided, the microstructure of the material is improved, the plasticity and toughness are improved, and the requirements of subsequent machining and application can be met.

Description

Technical Field

[0001] The invention belongs to the technical field of advanced material manufacturing, and relates to a pulse electric field coordinated vacuum annealing method for eliminating stress of ultra-thin wide titanium foil with a thickness of 0.01 to 0.1 mm and a width of more than 600 mm. Background Art

[0002] Ultra-thin wide titanium foil has a wide range of applications in aerospace, electronics, chemical industry, medical and other fields due to its excellent strength, corrosion resistance and biocompatibility. However, residual stress is easily generated in the preparation process of titanium foil strip, which leads to material deformation, dimensional instability, performance degradation and other problems, which seriously affect its application; especially in ultra-thin titanium foil with a thickness of 0.01-0.1 mm, the problem is more significant.

[0003] In the existing technology, conventional heat treatment and mechanical processing methods are difficult to effectively remove the residual stress of ultra-thin titanium foil, and are prone to material deformation, performance loss, and grain coarsening. The stress removal process is usually time-consuming and energy-intensive, affecting production efficiency. Especially in large-scale production, the lengthy annealing time will reduce the overall production capacity. In the current context of environmental protection and energy conservation, this problem is particularly prominent. At the same time, the existing technology is often difficult to ensure uniform stress release, which may lead to unstable performance of the final product during use, affecting reliability.

[0004] In summary, there is an urgent need for a technical process method for eliminating stress of ultra-thin wide titanium foil with a thickness of 0.01 to 0.1 mm and a width of more than 600 mm to overcome the shortcomings of the existing technology and fill the technical gap in this field. Summary of the invention

[0005] The purpose of the present invention is to provide a pulsed electric field coordinated vacuum annealing method for stress elimination of ultra-thin wide-width titanium foil. The method adopts vacuum argon protection and pulsed electric field coordination to effectively remove the internal residual stress of the ultra-thin wide-width titanium foil. The process is simple and efficient, and surface oxidation of the titanium foil is avoided, so as to overcome the shortcomings of the existing technology.

[0006] The process scheme of the present invention comprises the following steps:

[0007] S1. Clean and dry the precision titanium foil to remove residual dirt on the surface to ensure a smooth surface;

[0008] S2, applying pulse electric field coordinated stress relief annealing process path to the titanium foil in step 1, applying pulse current and stress relief according to preset process conditions and parameters;

[0009] S3, after stress relief annealing, the titanium foil material in step 2 is cooled to room temperature under the action of a pulse electric field to obtain a finished micron-grade titanium foil material.

[0010] Furthermore, the titanium foil material in S1 has a thickness of 0.01-0.1 mm and a width of more than 600 mm; the precision foil material is pure titanium or a titanium alloy series, such as grades TA1, TA2, TA4, etc.

[0011] Furthermore, the vacuum degree of S2 is 1×10 -4 (Pa), the protective atmosphere is argon.

[0012] Furthermore, the titanium foil stress relief annealing process described in S2 is controlled by a segmented temperature zone platform, the first temperature platform: firstly heats from 0°C to T1, and the holding time of this stage is 10 to 20 minutes in total;

[0013] Furthermore, the second temperature platform controlled by the segmented temperature zone platform continues to heat from T1 to T2, and the insulation time in this stage is 20 to 35 minutes in total.

[0014] Furthermore, in the pulse electric field and coordinated vacuum annealing process, the pulse current used in steps S2-S3 is direct current, and the process parameters are: current size: 10-400A, current density range: 10A / m²-500A / m²; electric field strength: 5-30kV / mm.

[0015] Furthermore, the amplitude and vibration frequency of the pulse signal are adjusted by controlling the voltage and pulse frequency of the pulse electric field, with the voltage range being 30 to 500 V and the pulse frequency being 1 Hz to 10 Hz.

[0016] Furthermore, the cooling process in S3 is protected by argon gas, and the cooling method is furnace cooling or water cooling + air cooling.

[0017] The beneficial effects of the present invention are:

[0018] The technical process path of pulse electric field coordinated vacuum annealing proposed in the present invention effectively removes the residual stress of titanium foil after being processed by this process method, significantly reduces the deformation and warping of the material, and avoids oxidation. At the same time, the microstructure of the material is improved, and the plasticity and toughness are improved, which can meet the needs of subsequent processing and application. At the same time, this technical process method fills the gap in this field, can effectively overcome the shortcomings of the existing technology, improve the performance and quality of the product, meet the requirements of energy saving and environmental protection, and can meet the processing and application needs of the current new energy, 3C precision electronics, and high-end technology frontier fields.

[0019] The innovative features of the present invention are as follows:

[0020] (1) The use of pulsed electric field coordinated vacuum annealing technology can effectively remove the residual stress inside the titanium foil, thereby avoiding material deformation and warping, further optimizing the microstructure of the titanium foil, and enhancing its plasticity and toughness to meet the needs of subsequent processing and application fields. At the same time, under vacuum conditions and argon protection, the oxidation of the titanium foil at high temperatures is effectively prevented, ensuring surface finish and mechanical properties. The process flow of the present invention is simple, easy to operate, has low equipment cost, and high processing efficiency, and is suitable for large-scale production. The technology has wide applicability and is suitable for ultra-thin wide-width pure titanium foils of various specifications with different thicknesses and widths.

[0021] (2) Compared with the traditional annealing method, the main difference lies in controlling the voltage and pulse frequency of the pulse electric field to adjust the amplitude and vibration frequency of the pulse signal. The thermal effect and shock effect generated by the synergistic effect of the pulse electric field and vacuum annealing change the arrangement of atoms and electrons, promote dislocation movement and grain boundary migration, effectively eliminate the residual stress inside the titanium foil, better control grain growth, and maintain excellent plate shape and mechanical properties. Therefore, the use of pulse electric field synergistic vacuum annealing technology provides a new process method for stress relief of titanium foil that is efficient, energy-saving, and can maintain material properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The present invention is a flow chart of the pulse electric field coordinated vacuum annealing method for stress elimination of ultra-thin wide titanium foil. DETAILED DESCRIPTION

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. The following description of at least one exemplary embodiment is actually only illustrative and is by no means a limitation on the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Embodiment 1:

[0025] Refer to the following Figure 1 A pulse electric field coordinated vacuum annealing method for stress relief of ultra-thin wide titanium foil according to an embodiment of the present invention is described, comprising the following steps:

[0026] S1. Specifications The TA4 titanium foil was cleaned and dried, and pulse electric field coordinated stress relief annealing was performed according to the preset process conditions and parameters. It was first heated from 0°C to T1 temperature platform. The holding time in this stage was 15 minutes. The annealing temperature was 240°C. The pulse current was direct current. The pulse electric field parameters used in the first temperature platform were: voltage: 200V, current: 160A, current density controlled at 50A / m²~180A / m²; pulse frequency: 4Hz, electric field strength: 18kV / mm; argon protection was used throughout the process, and the vacuum degree was controlled at 1×10 -4 (Pa);

[0027] S2. After the heat preservation is completed, continue heating from T1 to T2. The heat preservation time in this stage is 25min in total. The annealing temperature is 500℃. The pulse current is direct current. The pulse electric field parameters used in the second temperature platform are: voltage: 400V, current: 300A, current density controlled at 180A / m²~430A / m², pulse frequency: 4Hz, electric field strength: 27kV / mm; argon protection is used throughout the process, and the vacuum degree is controlled at 1×10 -4 (Pa);

[0028] S3. The titanium foil is cooled by furnace cooling. The cooling process is protected by argon gas and the pulse electric field effect remains unchanged. After cooling to room temperature, the finished TA4 titanium foil is obtained.

[0029] Finally, it should be noted that the above embodiments are only used as technical solutions rather than limitations of the present invention; although the present invention has been described in detail with reference to the embodiments, those skilled in the art should understand that modifications or equivalent substitutions of the technical solutions of the present invention do not depart from the spirit and scope of the technical solutions of the present invention, and should all be included in the scope of the claims of the present invention.

Claims

1. A pulse electric field coordinated vacuum annealing method for stress relief of ultra-thin wide titanium foil, characterized in that: The following steps are involved: S1. Clean and dry the precision titanium foil to remove residual dirt on the surface to ensure a smooth surface; S2, applying pulse electric field and vacuum annealing to remove stress on the titanium foil in step 1, and applying pulse current and stress removal according to preset process conditions and parameters; S3, after stress relief annealing, the titanium foil material in step 2 is cooled to room temperature under the action of a pulse electric field to obtain a finished micron-grade titanium foil material.

2. The pulse electric field coordinated vacuum annealing method for stress relief of ultra-thin wide titanium foil according to claim 1 is characterized in that: S1 The titanium foil material has a thickness of 0.01-0.1 mm and a width of more than 600 mm; the precision foil material is pure titanium or titanium alloy series, with grades TA1, TA2, and TA4.

3. The pulse electric field coordinated vacuum annealing method for stress relief of ultra-thin wide titanium foil according to claim 1 is characterized in that: The vacuum degree of S2 is 1×10 -4 (Pa), the protective atmosphere is argon.

4. The pulse electric field coordinated vacuum annealing method for stress relief of ultra-thin wide titanium foil according to claim 1 is characterized in that: The stress relief annealing process of S2 titanium foil adopts segmented temperature zone platform control. The first temperature platform: first heats from 0℃ to T1, and the insulation time in this stage is 10 to 20 minutes.

5. The pulse electric field coordinated vacuum annealing method for stress relief of ultra-thin wide titanium foil according to claim 4 is characterized in that: Second temperature platform: Continue heating from T1 to T2, and the total insulation time in this stage is 20 to 35 minutes.

6. The pulse electric field coordinated vacuum annealing method for stress relief of ultra-thin wide titanium foil according to claim 1, characterized in that: In the pulse electric field coordinated vacuum annealing process described in S3, the pulse current used in steps S2-S3 is direct current, and the process parameters are: current size: 10~400A, current density range: 10A / m²~500A / m²; electric field strength: 5~30kV / mm.

7. The pulse electric field coordinated vacuum annealing method for stress relief of ultra-thin wide titanium foil according to claim 6, characterized in that: The amplitude and vibration frequency of the pulse signal are adjusted by controlling the voltage and pulse frequency of the pulse electric field, the voltage range is: 30-500V, and the pulse frequency is: 1Hz-10Hz.

8. The pulse electric field coordinated vacuum annealing method for stress relief of ultra-thin wide titanium foil according to claim 1, characterized in that: S3 The cooling process is protected by argon gas, and the cooling method is furnace cooling or water cooling + air cooling.

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