CN113046543A - Wire freezing method - Google Patents
Wire freezing method Download PDFInfo
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- CN113046543A CN113046543A CN202110279086.6A CN202110279086A CN113046543A CN 113046543 A CN113046543 A CN 113046543A CN 202110279086 A CN202110279086 A CN 202110279086A CN 113046543 A CN113046543 A CN 113046543A
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- wire
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
- C21D9/525—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length for wire, for rods
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
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- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B1/00—Single-crystal growth directly from the solid state
- C30B1/02—Single-crystal growth directly from the solid state by thermal treatment, e.g. strain annealing
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- Crystallography & Structural Chemistry (AREA)
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Abstract
A wire freezing method belongs to the technical field of audio wires and aims to solve the problems in the prior art. The invention comprises the following steps: the method comprises the following steps: the wire is subjected to one-stage freezing treatment, which specifically comprises the following steps: 1) cooling the wire to the lowest temperature T by adopting liquid nitrogen, and storing for 24 hours under the conditions of constant temperature and constant pressure; 2) heating the wire to room temperature and standing for 12 hours at room temperature; step two: the wire is subjected to two-stage freezing treatment, which specifically comprises the following steps: 1) cooling the wire to-196 ℃ by adopting liquid nitrogen, and preserving for 18 hours under the conditions of constant temperature and constant pressure; 2) heating the wire to room temperature and standing for 12 hours at room temperature; step three: the wire is subjected to three-stage freezing treatment, which specifically comprises the following steps: 1) cooling the wire to-196 ℃ by adopting liquid nitrogen, and preserving for 12 hours under the conditions of constant temperature and constant pressure; 2) heating the wire to room temperature and standing for 12 hours at room temperature; step four: repeating the step three n times.
Description
Technical Field
The invention belongs to the technical field of wires, and particularly relates to a wire freezing method.
Background
The existing wire is usually a metal conductor such as oxygen-free copper, pure silver, gold and the like, the wire is formed by combining a plurality of metal crystal grains in an irregular arrangement mode on an internal structure, certain impurities and defects are accompanied among the crystal grains, the wire cannot be represented as a long-range ordered single crystal structure macroscopically, and the current conduction of the wire is influenced by the boundaries of the crystal grains, so that the sound representation is influenced.
Chinese patent publication No. CN102994920A discloses a method for reducing resistance of copper and copper alloy at high and low temperatures, which is only for copper and copper alloy, the material is too single, and the main current conductor used in the audio field includes, in addition to copper and copper alloy: copper silver plating, copper gold plating, pure silver, single crystal silver, silver alloy, silver gold plating, pure gold, gold alloy, including aluminum materials commonly used for horn coils, and the like.
In the prior art, all methods for processing the wire are oriented to industrial use and are not optimized for the electrification characteristics and the electro-acoustic technology of the wire. The metal grain gaps and the structure can not be effectively improved, and the scattering probability of electrons is reduced, so that the space is still greatly improved. The method cannot be carried out on finished wires: the method comprises the steps of integrally processing after the connection of a wire insulating sheath, various levels of shields and various plugs is finished.
Disclosure of Invention
The invention aims to provide a wire freezing method, which solves the problems that the prior art is single in material, limited in processing capacity, incapable of optimizing the electrification characteristics and the electro-acoustic technology of a wire, incapable of improving the metal grain structure and incapable of processing a finished wire.
In order to achieve the above object, a wire freezing method of the present invention comprises the steps of:
the method comprises the following steps: the wire is subjected to one-stage freezing treatment, which specifically comprises the following steps:
1) cooling the wire to the lowest temperature T by adopting liquid nitrogen, and storing for 24 hours under the conditions of constant temperature and constant pressure;
2) heating the wire to room temperature and standing for 12 hours at room temperature;
step two: the wire is subjected to two-stage freezing treatment, which specifically comprises the following steps:
1) cooling the wire to the lowest temperature T by adopting liquid nitrogen, and storing for 18 hours under the conditions of constant temperature and constant pressure;
2) heating the wire to room temperature and standing for 12 hours at room temperature;
step three: the wire is subjected to three-stage freezing treatment, which specifically comprises the following steps:
1) cooling the wire to the lowest temperature T by adopting liquid nitrogen, and storing for 12 hours under the conditions of constant temperature and constant pressure;
2) heating the wire to room temperature and standing for 12 hours at room temperature;
step four: repeating the step three n times;
the value range of the lowest temperature T in the first step, the second step and the third step is as follows: t is more than or equal to minus 193 ℃ and less than or equal to minus 196 ℃.
In the step 1) of the first step, the wire is cooled to the lowest temperature T by adopting liquid nitrogen, and the wire is slowly and uniformly cooled within 30 minutes.
The temperature of the wire rod is raised slowly and uniformly within 6 hours in the step 2) in the first step.
And in the step 1) in the step two, the wire is cooled to the lowest temperature T by adopting liquid nitrogen, and the wire is slowly and uniformly cooled within 60 minutes.
In the step 2) in the second step, the temperature of the wire rod is slowly and uniformly increased within 8 hours.
And step three), the wire is cooled to the lowest temperature T by adopting liquid nitrogen in step 1), and the wire is slowly and uniformly cooled within 90 minutes.
The temperature of the wire rod is raised in the step 2) in the third step to complete slow and uniform temperature rise within 12 hours.
The value range of n is as follows: n is more than or equal to 0.
The wire is a finished wire.
The temperature range of room temperature t referred to in the present invention is defined as: t is more than or equal to 18 ℃ and less than or equal to 22 ℃.
The invention has the beneficial effects that: the wire freezing method provided by the invention utilizes liquid nitrogen low-temperature freezing, and comprises special control of temperature, time, processing times, heating and cooling links, so that the original irregular crystal structure of metal is broken, and the metal conductor shows a long-range ordered single crystal structure. The grain boundary scattering during the electron transportation is reduced, so that the music performance is more exquisite and smooth, and the method is more suitable for the transmission of 20Hz-50kHz music signals. This application can be after the wire rod preparation is accomplished, and the finished product is whole to carry out the refrigeration treatment, and various metal materials such as the plug, tie point, shielding can all obtain same metal grain reforming promotion in doing so.
Drawings
FIG. 1 is a photograph of a crystal section of an oxygen-free copper wire without freezing treatment under a microscope;
FIG. 2 is a photograph of a crystal section of an oxygen-free copper wire subjected to only one stage of freezing treatment under a microscope;
FIG. 3 is a photograph of a crystal section of an oxygen-free copper wire subjected to one-stage freezing treatment and two-stage freezing treatment under a microscope;
FIG. 4 is a photograph of a crystal section of an oxygen-free copper wire subjected to one-stage freezing treatment, two-stage freezing treatment and three-stage freezing treatment under a microscope.
Detailed Description
The following further describes embodiments of the present invention with reference to the drawings.
The technical principle of the invention is as follows: the metal atom arrangement has periodicity, is expressed as body-centered cubic lattice or face-centered cubic lattice, forms a long-range ordered crystal structure and has a periodic potential field. Thermal shock of atoms will cause the crystal potential field to deviate from the periodic field, causing inelastic scattering of electrons, which macroscopically appears as a resistance proportional to the temperature T. Ideally, the metal resistance is due to electron scattering by thermal shock of the metal atoms.
As the microstructure of the metal conductor wire, most of them are typical units of face-centered cubic lattice. Common metals with such a structure include Cu, Ag, Au, Al, etc.
The solid materials actually used are mostly polycrystalline rather than single crystals of a single oriented lattice arrangement. This is due, firstly, to the fact that during the normal preparation of the material, for example during solidification in the high-temperature molten state, a solid metal is obtained, crystals form around a large number of different nuclei. It is natural that a polycrystal composed of many crystal grains is formed. The size of the grains may be as small as a micron or less, or as large as can be seen only clearly by the eye. The grain size, shape, and orientation distribution can all have a significant effect on the properties of the polycrystalline body. The boundary between grains is called grain boundary, which can be regarded as a crystal defect. The general grain boundary has only a few layers of atoms arranged in a disordered way, and a few layers of atoms arranged on both sides of the grain boundary are arranged according to a crystal lattice, but have larger distortion. Grain boundaries have a certain free energy as in the case of the interfaces of general objects. Generally, the crystal grain size of a polycrystalline body changes at different temperatures. Large grains gradually erode small grains. In particular the movement of grain boundaries. Atoms can diffuse relatively easily along grain boundaries. Foreign atoms can penetrate and be distributed at grain boundaries. Internal impurity atoms or inclusions also tend to concentrate at grain boundaries. These can impart complex properties to the grain boundaries, particularly with respect to current conduction. Therefore, in addition to the lattice vibration of atoms, the non-uniform grains of the actual metal material will also destroy the periodic potential field, causing T-independent electron scattering.
The wire freezing treatment method comprises the following steps:
the method comprises the following steps: the wire is subjected to one-stage freezing treatment, which specifically comprises the following steps:
1) cooling the wire to the lowest temperature T by adopting liquid nitrogen, and storing for 24 hours under the conditions of constant temperature and constant pressure;
2) heating the wire to room temperature and standing for 12 hours at room temperature;
step two: the wire is subjected to two-stage freezing treatment, which specifically comprises the following steps:
1) cooling the wire to the lowest temperature T by adopting liquid nitrogen, and storing for 18 hours under the conditions of constant temperature and constant pressure;
2) heating the wire to room temperature and standing for 12 hours at room temperature;
step three: the wire is subjected to three-stage freezing treatment, which specifically comprises the following steps:
1) cooling the wire to the lowest temperature T by adopting liquid nitrogen, and storing for 12 hours under the conditions of constant temperature and constant pressure;
2) heating the wire to room temperature and standing for 12 hours at room temperature;
step four: repeating the step three n times;
the value range of the lowest temperature T in the first step, the second step and the third step is as follows: t is more than or equal to minus 193 ℃ and less than or equal to minus 196 ℃. The temperature is selectively reduced to-196 ℃ in the implementation.
The temperature of the wire rod is reduced to-196 ℃ by adopting liquid nitrogen in the step 1) in the step one, and the temperature is slowly and uniformly reduced within 30 minutes.
The temperature of the wire rod is raised slowly and uniformly within 6 hours in the step 2) in the first step.
And in the step 1) in the step two, the wire is cooled to-196 ℃ by adopting liquid nitrogen, and the wire is slowly and uniformly cooled within 60 minutes.
In the step 2) in the second step, the temperature of the wire rod is slowly and uniformly increased within 8 hours.
The temperature of the wire rod is reduced to-196 ℃ by adopting liquid nitrogen in the step 1) in the third step, and the temperature is slowly and uniformly reduced within 90 minutes.
The temperature of the wire rod is raised in the step 2) in the third step to complete slow and uniform temperature rise within 12 hours.
The value range of n is as follows: n is more than or equal to 0. The value of n in this embodiment is 0, 1 or 2.
The wire is a finished wire.
Each freezing stage needs to have longer relaxation time in the room temperature static process, and high-temperature thermal radiation, strong magnetic resonance and laser irradiation are avoided, so that severe disturbance is avoided.
The-196 ℃ referred to in this application can also be replaced by 77K in the temperature Kelvin.
The resolution of the temperature measuring device is 1 ℃ or higher, the error is not more than +/-2 ℃ in the range of-40 ℃ to 10 ℃, and not more than +/-3 ℃ in the range of-196 ℃ to-40 ℃.
The action is finished in the existing constant-temperature and constant-pressure equipment, the slow and uniform cooling process is a process of slowly injecting liquid nitrogen, the slow heating process is a process of slowly pumping out the liquid nitrogen, and the amount of injected liquid nitrogen is related to parameters such as space, volume, performance and the like of the selected constant-temperature and constant-pressure equipment; the equipment specifically adopted in this embodiment is:
the type of the frozen workpiece storage container is as follows: YDS-10-210;
liquid nitrogen automatic supply and filling: YDZ-100;
a temperature detector: DTM 180A;
the type of the frozen workpiece storage container is as follows: YDS-10-210 is heat preservation and freezing execution equipment with the volume of 10 liters, and can be used for carrying out freezing treatment on wire workpieces with the volume within 10 liters.
Liquid nitrogen automatic supply and filling: YDZ-100: for a 100-liter liquid nitrogen constant-temperature and constant-pressure storage tank, YDZ-100 can adjust the pressure and flow rate according to the requirement to automatically supply liquid nitrogen to YDS-10-210, so that the temperature reduction time, the temperature rise time and the constant-temperature time are adjusted.
A temperature detector: the range of DTM180A from-200 to 200 ℃ is responsible for controlling the temperature measurement of temperature reduction, temperature rise and constant temperature, thereby carrying out fine adjustment on the equipment.
When adopting this constant temperature equipment:
for the slow cooling to-196 ℃ in the one-stage freezing, 12 liters of liquid nitrogen is uniformly injected into a constant temperature and constant pressure device within 30 minutes.
For the slow cooling to-196 ℃ in the two-stage freezing, 13.5 liters of liquid nitrogen is uniformly injected into a constant temperature and pressure device within 60 minutes.
The slow cooling to-196 ℃ for the three-stage freezing was carried out by uniformly injecting 16 liters of liquid nitrogen into a constant temperature and pressure equipment over 90 minutes.
The invention relates to a technical treatment method for freezing metal wires at ultralow temperature and then slowly raising the temperature. When the temperature is reduced, the coulomb energy formed by combining metal atoms is reduced, the free energy of crystal grains is reduced, the shape, the thickness and the direction distribution of the crystal grains are changed, and more regular and ordered single crystals are formed. The influence on the electron free path is reduced, and the electron scattering probability is reduced. When the temperature slowly rises to room temperature, the metal will continue to maintain a low energy state and the crystalline state is retained. Through several times of circulating operation, original crystal grains of metal which are distributed unevenly are broken, and the metal grains are fused into larger and more complete single crystals with uniform spatial terms and the same property. The method utilizes a special freezing technology to reform the internal crystal grains of the metal to achieve the space isotropy. The metal processed by deep cooling is in a single crystal form, the electron scattering problem caused by the metal grain boundary is solved by the macroscopic effect, and the resistivity is reduced.
This application is all effective to the mainstream conductor that uses in stereo set field now, all can use.
The change in impedance after three-stage freezing for each metal using a kelvin bridge is tabulated as:
wherein: r0The meaning is as follows: the original impedance;
the meaning of R: impedance after freezing treatment;
The table shows that the freezing method has obvious improvement on the conductivity, has obvious difference from audibility aiming at weak audio signals, and is more sensitive to the weak fluctuation reaction of voltage and current signals with the transmission frequency of 20Hz-50 kHz.
Referring to fig. 1-4, comparative photographs of the grain change at each stage of three-stage freezing under a microscope of 250 x. The material is taken as an example of the same oxygen-free copper wire core with the diameter of 0.5mm, and 4 sections are cut out and then are respectively subjected to different stages of freezing treatment.
The picture shows that the crystal grain is obviously changed after each stage of freezing, the crystal boundary is gradually reduced, and the cross section of the conductor is smoother.
The invention mainly uses a freezing treatment method aiming at the wire conductor, does not limit the conductor material and specification, and can be used on most wires, thereby improving the restoring capability of music, improving the conduction characteristic of the conductor to audio electric signals, reducing the impedance loss and the distortion of tone quality, and greatly ensuring the high fidelity characteristic of the music. The invention can be used in the finished product state after the wire rod is manufactured, and the wire rod treated by the invention can not be damaged as long as the material of the insulator is noticed. The invention can change the conductor itself, and also change the front of the plug and the shield. The invention does not limit the number of times of repeated freezing, and theoretically, the more the freezing times are, the closer the conductor is to the perfect conductor.
The freezing treatment method of the invention is not limited to audio signal wires, and the industrial cables are provided with cables and signal cables which are also effective.
Claims (8)
1. A wire freezing method is characterized by comprising the following steps:
the method comprises the following steps: the wire is subjected to one-stage freezing treatment, which specifically comprises the following steps:
1) cooling the wire to the lowest temperature T by adopting liquid nitrogen, and storing for 24 hours under the conditions of constant temperature and constant pressure;
2) heating the wire to room temperature and standing for 12 hours at room temperature;
step two: the wire is subjected to two-stage freezing treatment, which specifically comprises the following steps:
1) cooling the wire to the lowest temperature T by adopting liquid nitrogen, and storing for 18 hours under the conditions of constant temperature and constant pressure;
2) heating the wire to room temperature and standing for 12 hours at room temperature;
step three: the wire is subjected to three-stage freezing treatment, which specifically comprises the following steps:
1) cooling the wire to the lowest temperature T by adopting liquid nitrogen, and storing for 12 hours under the conditions of constant temperature and constant pressure;
2) heating the wire to room temperature and standing for 12 hours at room temperature;
step four: repeating the step three n times;
the value range of the lowest temperature T in the first step, the second step and the third step is as follows: t is more than or equal to minus 193 ℃ and less than or equal to minus 196 ℃.
2. The wire freezing method according to claim 1, wherein the step 1) of the first step of cooling the wire to the lowest temperature T by using liquid nitrogen is a step of slowly and uniformly cooling the wire within 30 minutes.
3. A wire freezing method as claimed in claim 1, wherein the temperature of the wire in step 2) in the first step is raised to a slow uniform temperature within 6 hours.
4. The wire freezing method according to claim 1, wherein the step 1) in the second step of cooling the wire to the lowest temperature T by using liquid nitrogen is to complete slow and uniform cooling within 60 minutes.
5. A wire freezing method as claimed in claim 1, wherein the temperature of the wire in step 2) in step two is raised to a slow uniform temperature within 8 hours.
6. The wire freezing method according to claim 1, wherein the step 1) of the third step is a step of slowly and uniformly cooling the wire to the lowest temperature T by using liquid nitrogen within 90 minutes.
7. A wire freezing method as claimed in claim 1, wherein the temperature of the wire in step 2) in step three is raised to a slow uniform temperature within 12 hours.
8. A wire freezing method according to any one of claims 1 to 7, wherein n is selected from the range: n is more than or equal to 0.
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Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
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CN103614677A (en) * | 2013-12-06 | 2014-03-05 | 上海田伏电子科技有限公司 | Subzero treatment process of copper material |
CN105401110A (en) * | 2015-12-25 | 2016-03-16 | 常州大学 | Cryogenic treatment technology of aluminum bronze |
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Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
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CN103614677A (en) * | 2013-12-06 | 2014-03-05 | 上海田伏电子科技有限公司 | Subzero treatment process of copper material |
CN105401110A (en) * | 2015-12-25 | 2016-03-16 | 常州大学 | Cryogenic treatment technology of aluminum bronze |
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