CN111304475A - High-performance aluminum material for air conditioner connecting pipe and preparation method thereof - Google Patents
High-performance aluminum material for air conditioner connecting pipe and preparation method thereof Download PDFInfo
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- 229910052782 aluminium Inorganic materials 0.000 title claims abstract description 154
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 title claims abstract description 145
- 239000000463 material Substances 0.000 title claims abstract description 42
- 238000002360 preparation method Methods 0.000 title claims abstract description 9
- 238000007670 refining Methods 0.000 claims abstract description 45
- 238000000034 method Methods 0.000 claims abstract description 28
- 238000000137 annealing Methods 0.000 claims abstract description 24
- 238000005096 rolling process Methods 0.000 claims abstract description 21
- 239000000956 alloy Substances 0.000 claims abstract description 17
- 239000002994 raw material Substances 0.000 claims abstract description 13
- 238000001125 extrusion Methods 0.000 claims abstract description 9
- 238000009749 continuous casting Methods 0.000 claims abstract description 6
- 238000003723 Smelting Methods 0.000 claims abstract description 4
- 238000005275 alloying Methods 0.000 claims abstract description 4
- 239000007788 liquid Substances 0.000 claims description 67
- 238000005070 sampling Methods 0.000 claims description 23
- 238000005266 casting Methods 0.000 claims description 22
- 238000004321 preservation Methods 0.000 claims description 21
- 239000010949 copper Substances 0.000 claims description 20
- 239000003795 chemical substances by application Substances 0.000 claims description 17
- 229910052802 copper Inorganic materials 0.000 claims description 17
- 229910045601 alloy Inorganic materials 0.000 claims description 15
- 238000003756 stirring Methods 0.000 claims description 15
- 238000007872 degassing Methods 0.000 claims description 13
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 11
- 239000011572 manganese Substances 0.000 claims description 11
- 239000010936 titanium Substances 0.000 claims description 11
- 229910052742 iron Inorganic materials 0.000 claims description 10
- 229910052748 manganese Inorganic materials 0.000 claims description 10
- 229910052719 titanium Inorganic materials 0.000 claims description 10
- -1 aluminum-manganese Chemical compound 0.000 claims description 9
- 229910052761 rare earth metal Inorganic materials 0.000 claims description 9
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 8
- 238000002844 melting Methods 0.000 claims description 8
- 230000008018 melting Effects 0.000 claims description 8
- CSDREXVUYHZDNP-UHFFFAOYSA-N alumanylidynesilicon Chemical compound [Al].[Si] CSDREXVUYHZDNP-UHFFFAOYSA-N 0.000 claims description 7
- WPPDFTBPZNZZRP-UHFFFAOYSA-N aluminum copper Chemical compound [Al].[Cu] WPPDFTBPZNZZRP-UHFFFAOYSA-N 0.000 claims description 7
- CYUOWZRAOZFACA-UHFFFAOYSA-N aluminum iron Chemical compound [Al].[Fe] CYUOWZRAOZFACA-UHFFFAOYSA-N 0.000 claims description 7
- 239000000155 melt Substances 0.000 claims description 7
- 229910001069 Ti alloy Inorganic materials 0.000 claims description 6
- UQZIWOQVLUASCR-UHFFFAOYSA-N alumane;titanium Chemical compound [AlH3].[Ti] UQZIWOQVLUASCR-UHFFFAOYSA-N 0.000 claims description 6
- 229910000881 Cu alloy Inorganic materials 0.000 claims description 5
- 229910000640 Fe alloy Inorganic materials 0.000 claims description 5
- 229910000914 Mn alloy Inorganic materials 0.000 claims description 5
- 229910000676 Si alloy Inorganic materials 0.000 claims description 5
- 229910000831 Steel Inorganic materials 0.000 claims description 5
- 238000001816 cooling Methods 0.000 claims description 5
- 238000010438 heat treatment Methods 0.000 claims description 5
- 239000000843 powder Substances 0.000 claims description 5
- 239000010959 steel Substances 0.000 claims description 5
- 229910052684 Cerium Inorganic materials 0.000 claims description 4
- 238000007664 blowing Methods 0.000 claims description 4
- 239000000498 cooling water Substances 0.000 claims description 4
- 238000002425 crystallisation Methods 0.000 claims description 4
- 230000008025 crystallization Effects 0.000 claims description 4
- 238000001914 filtration Methods 0.000 claims description 4
- 239000011261 inert gas Substances 0.000 claims description 4
- 229910052746 lanthanum Inorganic materials 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 claims description 4
- 229910000789 Aluminium-silicon alloy Inorganic materials 0.000 claims description 3
- 238000004378 air conditioning Methods 0.000 claims description 3
- 238000013459 approach Methods 0.000 claims description 3
- 238000002156 mixing Methods 0.000 claims description 3
- 229910052757 nitrogen Inorganic materials 0.000 claims description 3
- 229910052710 silicon Inorganic materials 0.000 claims description 3
- 238000002347 injection Methods 0.000 claims description 2
- 239000007924 injection Substances 0.000 claims description 2
- 239000002893 slag Substances 0.000 claims 1
- 238000005260 corrosion Methods 0.000 abstract description 10
- 230000007797 corrosion Effects 0.000 abstract description 10
- 229910000838 Al alloy Inorganic materials 0.000 abstract description 9
- 238000003466 welding Methods 0.000 description 8
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 7
- 239000000839 emulsion Substances 0.000 description 5
- WCUXLLCKKVVCTQ-UHFFFAOYSA-M Potassium chloride Chemical compound [Cl-].[K+] WCUXLLCKKVVCTQ-UHFFFAOYSA-M 0.000 description 4
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000011159 matrix material Substances 0.000 description 3
- 238000005507 spraying Methods 0.000 description 3
- 229910001610 cryolite Inorganic materials 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 229910001873 dinitrogen Inorganic materials 0.000 description 2
- 238000003912 environmental pollution Methods 0.000 description 2
- 238000007689 inspection Methods 0.000 description 2
- 230000007774 longterm Effects 0.000 description 2
- 239000001103 potassium chloride Substances 0.000 description 2
- 235000011164 potassium chloride Nutrition 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 239000011780 sodium chloride Substances 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- JRBRVDCKNXZZGH-UHFFFAOYSA-N alumane;copper Chemical compound [AlH3].[Cu] JRBRVDCKNXZZGH-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- IYRDVAUFQZOLSB-UHFFFAOYSA-N copper iron Chemical compound [Fe].[Cu] IYRDVAUFQZOLSB-UHFFFAOYSA-N 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 238000003487 electrochemical reaction Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000010309 melting process Methods 0.000 description 1
- 238000010943 off-gassing Methods 0.000 description 1
- 239000012188 paraffin wax Substances 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 239000003507 refrigerant Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 235000011121 sodium hydroxide Nutrition 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 238000005482 strain hardening Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/02—Making non-ferrous alloys by melting
- C22C1/03—Making non-ferrous alloys by melting using master alloys
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/02—Making non-ferrous alloys by melting
- C22C1/026—Alloys based on aluminium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C21/00—Alloys based on aluminium
-
- 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
- C22F1/04—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F1/00—Room units for air-conditioning, e.g. separate or self-contained units or units receiving primary air from a central station
- F24F1/06—Separate outdoor units, e.g. outdoor unit to be linked to a separate room comprising a compressor and a heat exchanger
- F24F1/26—Refrigerant piping
- F24F1/32—Refrigerant piping for connecting the separate outdoor units to indoor units
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Combustion & Propulsion (AREA)
- General Engineering & Computer Science (AREA)
- Continuous Casting (AREA)
Abstract
The invention discloses a preparation method of a high-performance aluminum material, which comprises the steps of raw material selection and smelting, molten aluminum component analysis, alloying treatment, refining, slagging-off, component adjustment, external refining and deslagging, continuous casting, continuous rolling and annealing treatment. The invention also discloses the aluminum material prepared by the method and an air conditioner connecting pipe prepared from the high-performance aluminum material. The high-performance aluminum material prepared by the method disclosed by the invention has good corrosion resistance and fatigue resistance, and the tensile strength of the aluminum material meets the requirements of the aluminum alloy material of the air conditioner connector for extrusion molding.
Description
Technical Field
The invention relates to the field of alloy materials, in particular to a high-performance aluminum material for an air conditioner connecting pipe and a process preparation method thereof.
Background
When the household air conditioner is installed, an inner machine and an outer machine are required to be connected through connecting pipes, and air conditioner refrigerants exchange heat in the evaporator and the condenser through the connecting pipes. As a material for connecting pipes, the air-conditioning connecting pipe needs to bear large temperature difference for a long time during normal operation, so that the connecting pipe is easy to generate chamber fatigue fracture; and the connecting pipe is seriously corroded due to long-term contact with a cooling medium, and needs to be replaced at intervals.
As shown in fig. 1, most of the existing air conditioner connecting pipes are made of pure aluminum, and copper pipes are welded at two ends of the existing air conditioner connecting pipes. The purpose of adopting this kind of structure is to reduce the quantity of middle copper, save the cost; however, if pure aluminum is used, the strength of the aluminum alloy cannot reach the standard, the head is easily corroded, the corrosion resistance is poor, and fatigue fracture is easily caused. Therefore, the copper pipes are welded at the two ends, the strength of the connecting pipe part is guaranteed, and the toughness of the joint is improved. However, the air conditioner connecting pipe with the structure has complex welding process, brings environmental pollution and increases the process cost; in addition, in the long-term working process, electrochemical reaction is easy to occur at the copper-aluminum joint, so that the corrosion of the connecting pipe part is aggravated, and the welding port is easy to fall off.
Therefore, it is highly desirable to provide a high performance aluminum material for use in the preparation of air conditioner connecting pipes.
Disclosure of Invention
The invention aims to provide a preparation method of a high-performance aluminum material, which improves the corrosion resistance and the fatigue resistance of the aluminum alloy.
In order to solve the technical problems, the invention provides the following technical scheme:
in a first aspect, the present invention provides a method for preparing a high-performance aluminum material, comprising the steps of:
s1, raw material selection and smelting: selecting an aluminum ingot, an aluminum-silicon alloy, an aluminum-iron alloy, an aluminum-copper alloy, an aluminum-manganese alloy, an aluminum-rare earth alloy and an aluminum-titanium alloy as raw materials according to the following component proportion, batching, and putting the aluminum ingot into a melting furnace for melting: si: 0.03 to 0.08 wt%, Fe: 0.25 to 0.40 wt%, Cu: 0.25 to 0.45 wt%, Mn: 0.75 to 0.95 wt%, Ti: 0.007-0.015 wt%, RE: 0.005 to 0.18 wt%, Al: the balance, wherein RE is La and Ce with the proportion of 1: 2;
s2, analyzing the components of the aluminum liquid: transferring the smelted aluminum liquid to a holding furnace, uniformly stirring, sampling, performing component analysis, and detecting the contents of Al, Si, Fe, Cu, Mn, RE and Ti in the aluminum liquid;
s3, alloying treatment: controlling the temperature of the aluminum liquid in the heat preservation furnace to be 740 +/-10 ℃, adding aluminum-silicon alloy, aluminum-iron alloy, aluminum-copper alloy, aluminum-manganese alloy, aluminum-rare earth alloy and aluminum-titanium alloy into the furnace, and stirring to ensure that the aluminum liquid is uniform;
s4, refining: when the temperature of the aluminum liquid reaches 750 +/-10 ℃, introducing a refining agent into the aluminum liquid in the heat preservation furnace for refining;
s5, slagging off: after refining, heating the aluminum liquid, standing the melt for 5-10 minutes, opening a slagging-off door of a heat preservation furnace to carry out slagging-off when the temperature of the aluminum liquid is more than or equal to 730 ℃, and completely slagging off the scum on the surface of the aluminum liquid;
s6, component adjustment: sampling aluminum liquid from the furnace for component analysis, and confirming that the components of the aluminum liquid are as follows: si: 0.03 to 0.08 wt%, Fe: 0.25 to 0.40 wt%, Cu: 0.25 to 0.45 wt%, Mn: 0.75 to 0.95 wt%, Ti: 0.007-0.015 wt%, RE: 0.005-0.18 wt%; if the sampling result does not accord with the components, adjusting, and sampling and analyzing; if the sampling result meets the requirement, controlling the temperature of the aluminum liquid to be 740 +/-10 ℃, and blowing in the furnace and releasing;
s7, refining outside the furnace and deslagging: introducing the molten aluminum into an online degassing device and a filtering device in sequence, carrying out secondary refining, and degassing and deslagging again;
s8, continuous casting: continuously casting the molten aluminum refined again, wherein the casting temperature is 675-695 ℃, and the casting blank temperature on the approach bridge is 530-570 ℃;
s9, continuous rolling: continuously rolling the cast blank obtained by casting, wherein the rolling temperature is controlled to be 530-560 ℃, and the final rolling temperature is less than or equal to 300 ℃;
s10, annealing treatment: annealing the rolled aluminum material at 460-510 ℃ for 12 h.
Further, in step S1, pure is selectedAluminum ingot and AlSi with the degree of more than or equal to 99.7 percent12、AlFe20、AlCu50、AlMn10、AlRE10And AlTi10The raw materials are used for mixing.
Further, in the step S2, the temperature of the heat preservation is 750-780 ℃.
Further, in step S3, the aluminum liquid is sampled immediately after being stirred uniformly, stokehole analysis is performed, feeding is determined according to the analysis result, the aluminum liquid components are controlled to reach the target value, and the sampling temperature is 740 and 760 ℃.
Further, in step S4, the refining agent is a powder injection refining agent, the amount of the refining agent is 0.4% of the total amount of the furnace burden, the carrier of the refining agent is high-purity nitrogen with the purity of 99.999%, the refining time is not less than 45 minutes, and the refining temperature is 750-780 ℃.
Further, in step S5, after slagging-off is completed, the aluminum liquid is allowed to stand in the heat preservation furnace for 30-40 minutes, and the temperature of the aluminum liquid is kept at 740 +/-10 ℃.
Further, in step S8, the casting process adopts a steel strip and U-shaped crystallization wheel cooling method around the casting blank, and the temperature of the cooling water is controlled to be 25 ± 5 ℃.
Further, in step S10, the rolled aluminum material is protected by inert gas, and placed in a well-type annealing furnace or a box-type annealing furnace for a complete annealing process, wherein the annealing temperature is 460-.
In a second aspect, the present invention also provides a high performance aluminum material prepared by the method of the first aspect, wherein the high performance aluminum material comprises the following components: si: 0.03 to 0.08 wt%, Fe: 0.25 to 0.40 wt%, Cu: 0.25 to 0.45 wt%, Mn: 0.75 to 0.95 wt%, Ti: 0.007-0.015 wt%, RE: 0.005 to 0.18 wt%, Al: the balance, wherein RE is La and Ce, and the ratio is 1: 2.
In a third aspect, the invention provides an air conditioner connecting pipe, which is prepared from the high-performance aluminum material of the second aspect through an extrusion forming process.
The invention has the beneficial effects that:
1. according to the invention, the content of the Cu element in the formula is increased to 0.25-0.45 wt%, so that the processing performance of the alloy is improved, and the alloy is convenient to process into a hollow tubular part; but the corrosion resistance of the aluminum alloy is reduced by increasing the content of the Cu element, and the corrosion resistance of the alloy is improved and the influence of the increase of the content of the Cu element is eliminated by controlling the content of the Fe element to be 0.25-0.40 wt%, the content of the Mn element to be 0.75-0.95 wt% and the content of the Ti element to be 0.007-0.015 wt% in the formula.
2. As a material for connecting pipes, it is necessary to withstand high temperatures for a long period of time during normal operation, and the load that the alloy can withstand is correspondingly reduced by the effect of high-temperature creep. Therefore, the invention reduces the adverse effect on the selection of the aluminum alloy components by controlling the iron-copper ratio and adding a proper amount of rare earth elements.
3. In the invention, the main function of adding the manganese element is to improve the fatigue resistance of the material, and meanwhile, the addition of part of rare earth elements can also effectively improve the fatigue resistance and the corrosion resistance of the material.
4. According to the air conditioner connecting pipe, the copper pipes at two ends are replaced by the all-aluminum alloy sleeves, so that the problems that an aluminum alloy welding interface is poor and the aluminum alloy welding interface is easy to fall off are solved; meanwhile, the corrosion resistance is good, and the coating can be used for a long time without replacement.
Drawings
FIG. 1 is a schematic view of a prior art air conditioner connection tube;
wherein: 1. a pure aluminum material; 2. a copper material; 3. and (7) welding the port.
Detailed Description
The present invention is further described below in conjunction with the following figures and specific examples so that those skilled in the art may better understand the present invention and practice it, but the examples are not intended to limit the present invention.
As described in the background art, most of the existing air conditioner connecting pipes are made of pure aluminum, and copper pipes are welded at two ends of the existing air conditioner connecting pipes. The purpose of welding the copper pipe is to improve the toughness of the joint. However, the welding process is complicated, environmental pollution is caused, the process cost is increased, and the welding port is easy to fall off.
Based on the research, the inventor provides a preparation method of a high-performance aluminum material, and the high-performance aluminum material can be prepared into an air conditioner connecting pipe or other parts through extrusion forming. The method comprises the following specific steps:
s1, raw material selection and smelting:
selecting an aluminum ingot, an aluminum-silicon alloy, an aluminum-iron alloy, an aluminum-copper alloy, an aluminum-manganese alloy, an aluminum-rare earth alloy and an aluminum-titanium alloy as raw materials according to the following component proportion for proportioning: si: 0.03 to 0.08 wt%, Fe: 0.25 to 0.40 wt%, Cu: 0.25 to 0.45 wt%, Mn: 0.75 to 0.95 wt%, Ti: 0.007-0.015 wt%, RE: 0.005 to 0.18 wt%, Al: the balance, wherein RE is La and Ce, and the ratio is 1: 2.
The aluminum ingot in the invention can adopt industrial Al99.70 pure aluminum, and has the advantages of sufficient supply, low cost and convenient purchase. Meanwhile, the aluminum matrix can also adopt refined aluminum or high-purity aluminum as matrix alloy, the aluminum matrix has higher quality than common aluminum-based materials, and the processed product has more advantages in electrical property and mechanical property.
In the invention, other alloy can be selected from AlSi12、AlFe20、AlCu50、AlMn10、AlRE10And AlTi10The raw materials are used for mixing.
Before batching, the raw materials are firstly checked and selected. The purpose of the test is: ensures that each component meets the process requirements of the product and prevents each component from exceeding the range.
And then, putting the aluminum ingot meeting the requirements after the inspection into a melting furnace, and heating to melt the aluminum ingot. In the melting process, the temperature of the aluminum liquid in the furnace is controlled to be less than or equal to 760 ℃.
And when the temperature of the aluminum liquid in the furnace is more than or equal to 720 ℃, transferring the aluminum liquid into a heat preservation furnace, uniformly stirring, and preserving heat at 750-780 ℃.
S2, analyzing the components of the aluminum liquid: and sampling from the aluminum liquid, and detecting the contents of Al, Si, Fe, Cu, Mn, RE, Ti and other elements in the aluminum liquid. And correcting the required addition of aluminum silicon, aluminum iron, aluminum copper, aluminum manganese, aluminum rare earth and aluminum titanium alloy according to the inspection result, the total feeding amount of the aluminum ingot and the components of each intermediate alloy.
Preferably, a direct-reading spectrometer is used for rapid analysis of the content of each component.
S3, alloying treatment: controlling the temperature of the aluminum liquid in the heat preservation furnace to be 740 +/-10 ℃, and adding aluminum silicon, aluminum iron, aluminum copper, aluminum manganese and aluminum rare earth alloy. And after the intermediate alloy is put into the furnace, fully stirring the melt in the furnace to ensure that the components of the molten aluminum are uniform.
Preferably, manual and electromagnetic stirring is adopted, and the stirring time is more than or equal to 30 minutes.
Preferably, sampling is carried out immediately after uniform stirring, stokehole analysis is carried out, feeding is determined according to the analysis result, and the aluminum liquid component is controlled to reach the target value. The sampling temperature is preferably 740 ℃ and 760 ℃.
S4, refining: controlling the temperature of the aluminum liquid to be 750 +/-10 ℃, adopting air flow as a carrier, introducing a powder spraying refining agent into a melt in a heat preservation furnace for refining, and fully stirring the aluminum liquid to achieve the purposes of purification treatment such as degassing and impurity removal of the aluminum liquid.
Preferably, high purity nitrogen gas at a concentration of 99.999% is used as the carrier.
Preferably, the refining time is controlled to be 45 minutes or more and the refining temperature is controlled to be 750 to 780 ℃ by controlling the blowing speed of the refining agent and the pressure of nitrogen gas during refining.
Preferably, the main components of the powder spraying refining agent are sodium chloride, potassium chloride and cryolite, and the dosage of the refining agent is 0.4% of the total amount of the furnace charge.
S5, slagging off: after refining, heating the aluminum liquid, standing the melt for 5-10 minutes, opening a slagging-off door of a heat preservation furnace to carry out slagging-off when the temperature of the aluminum liquid is more than or equal to 730 ℃, and completely slagging off the scum on the surface of the aluminum liquid.
S6, component adjustment: after slagging off is finished, allowing the aluminum liquid to stand in the heat preservation furnace for 30-40 minutes, then sampling and analyzing to confirm that the chemical components of the aluminum liquid are as follows: si: 0.03 to 0.08 wt%, Fe: 0.25 to 0.40 wt%, Cu: 0.25 to 0.45 wt%, Mn: 0.75 to 0.95 wt%, Ti: 0.007-0.015 wt%, RE: 0.005-0.18 wt%; if the sampling result does not accord with the components, adjusting, and sampling and analyzing; if the sampling result meets the requirement, controlling the temperature of the aluminum liquid to be 740 +/-10 ℃, and blowing in the furnace for releasing.
Preferably, the temperature of the aluminum liquid is kept at 740 +/-10 ℃ before sampling.
Preferably, the sampling locations are at least 3 different places and are evenly distributed. If the sampling result is not consistent with the above components, the adjustment should be performed, and the sample is again stirred and stood for analysis.
S7, refining outside the furnace and deslagging: and introducing the molten aluminum into an online degassing device and a filtering device in sequence, carrying out secondary refining, and degassing and deslagging again.
Preferably, in order to control harmful gases in the molten aluminum, a degassing system is adopted for processing, and a hydrogen detector is adopted for detection; after degassing, a deslagging instrument is adopted to deslag so as to monitor the deslagging effect.
Preferably, the filter device is a dual stage ceramic filter plate having a pore size of 40PPI and 60 PPI.
The index requirements for outgassing are as follows:
| before on-line degassing/. ltoreq. | After in-line degassing/. ltoreq. |
| 0.300ml/100g | 0.15ml/100g |
S8, continuous casting: and continuously casting the re-refined aluminum liquid, wherein the casting temperature is 675-695 ℃, and the casting blank temperature on the approach bridge is 530-570 ℃.
Preferably, the casting process adopts a surrounding and surrounding cooling method of a steel belt and a U-shaped crystallization wheel to mold a casting blank, and the temperature of cooling water is controlled to be 25 +/-5 ℃.
S9, continuous rolling: and continuously rolling the cast blank obtained by casting, wherein the rolling temperature is controlled to be 530-560 ℃, and the final rolling temperature is less than or equal to 300 ℃.
The roll and the aluminum rod are preferably lubricated and cooled with an emulsion during rolling. The emulsion can be conventional aluminum tandem rolling emulsion, and the concentration of the emulsion is preferably 12-16%. More preferably, the emulsion has a concentration of 14%, a temperature of 65 ℃ and a pressure of 0.25 MPa.
S10, annealing treatment: annealing the rolled aluminum material at 460-510 ℃ for 12 h.
The aluminum alloy rod produced by the continuous casting and rolling line is extruded into a connector through a Conform extrusion device. However, the aluminum rod produced by continuous casting and rolling is in a work hardening state, is not easy to form in the extrusion process, has poor fluidity and needs to be subjected to complete annealing treatment.
Preferably, the rolled aluminum material is protected by inert gas and placed in a well type annealing furnace or a box type annealing furnace for a complete annealing process, wherein the annealing temperature is 460-510 ℃, the temperature rise time is 2-3h, and the heat preservation time is 12 h.
Examples 1 to 4: preparation of rolled aluminum rods
1. Raw material batching
The raw materials are mixed according to the component proportion in the table, and Al99.70 remelting aluminum ingot and AlSi are selected12、AlMn10、AlFe20、AlCu50、AlTi10And AlRE10As a starting material.
2. And (3) putting the aluminum ingot into a melting furnace for melting, transferring the aluminum ingot into a heat preservation furnace for uniformly stirring when the temperature of the molten aluminum in the melting furnace is more than or equal to 720 ℃, and preserving heat at 750-780 ℃. And detecting the content of each component in the aluminum liquid by adopting a direct-reading spectrometer. When the temperature of the aluminum liquid in the heat preservation furnace is 740 +/-10 ℃, adding other alloys, and fully stirring the melt in the furnace (manual stirring and electromagnetic stirring), wherein the stirring time is as follows: the time is more than or equal to 30 minutes, so that the components of the aluminum liquid are uniform. The powder spraying refining agent (the main components are sodium chloride, potassium chloride and cryolite) is adopted for refining, the dosage of the refining agent is 0.4 percent of the total amount of furnace burden, the refining agent is blown into molten aluminum in the furnace by high-purity nitrogen with the purity of 99.999 percent for refining, and the molten aluminum is fully stirred again. And after refining, heating the aluminum liquid, standing the melt for 5-10 minutes, opening a slagging-off door of the heat preservation furnace to carry out slagging-off when the temperature of the aluminum liquid is more than or equal to 730 ℃, and completely slagging off the scum on the surface of the aluminum liquid. And after slagging off is finished, allowing the aluminum liquid to stand in the heat preservation furnace for 30-40 minutes, and keeping the temperature of the aluminum liquid at 740 +/-10 ℃. And then sampling the aluminum liquid in the furnace for analysis, and determining whether the aluminum liquid needs to be adjusted. And if the components of the aluminum liquid meet the requirements and the temperature reaches 740 +/-10 ℃, discharging the aluminum liquid out of the heat preservation furnace, passing the aluminum liquid through a launder, entering an online degassing device and a filtering device, carrying out external refining, and degassing and deslagging again.
3. Continuously casting the aluminum liquid, wherein the casting temperature is controlled at 675-695 ℃; in the casting process, a steel belt and U-shaped crystallization wheel surrounding and cooling method is adopted to mold a casting blank, and the temperature of cooling water is controlled to be 25 +/-5 ℃.
4. And continuously rolling the cast aluminum blank, wherein the initial temperature is controlled to be 530-560 ℃ during rolling, and the final rolling temperature is less than or equal to 300 ℃.
5. And (3) rapidly adopting inert gas for protection after rolling, placing the rolled aluminum rod in a well type goods returning furnace or a box type annealing furnace for a complete annealing process, wherein the annealing temperature is 480 ℃, the temperature rise time is 1h, and the heat preservation time is 12h, and the complete annealing process is used for improving the good fluidity of the subsequent extrusion process.
6. And (5) placing the annealed aluminum rod for air cooling.
7. The aluminum rod is cleaned by 0.1% caustic soda solution, and is decontaminated by a steel brush.
8. 2 aluminum rods are fed into the aluminum rod at the same time, extrusion forming is carried out, and the extrusion temperature is controlled to be 350 +/-20 ℃. Controlling the proportion of the flash to be 8-15%.
9. After being extruded, the surface is coated with paraffin, so that the corrosion resistance can be further improved.
Material property detection
The performance parameters of the rolled aluminum rods prepared in examples 1-4 are shown in the following table:
therefore, the high-performance aluminum material prepared by the invention meets the requirements on strength, corrosion resistance and cycle fatigue resistance, and can be used for manufacturing air conditioner connectors.
The above-mentioned embodiments are merely preferred embodiments for fully illustrating the present invention, and the scope of the present invention is not limited thereto. The equivalent substitution or change made by the technical personnel in the technical field on the basis of the invention is all within the protection scope of the invention. The protection scope of the invention is subject to the claims.
Claims (10)
1. A preparation method of a high-performance aluminum material is characterized by comprising the following steps:
s1, raw material selection and smelting: selecting an aluminum ingot, an aluminum-silicon alloy, an aluminum-iron alloy, an aluminum-copper alloy, an aluminum-manganese alloy, an aluminum-rare earth alloy and an aluminum-titanium alloy as raw materials according to the following component proportion, batching, and putting the aluminum ingot into a melting furnace for melting: si: 0.03 to 0.08 wt%, Fe: 0.25 to 0.40 wt%, Cu: 0.25 to 0.45 wt%, Mn: 0.75 to 0.95 wt%, Ti: 0.007-0.015 wt%, RE: 0.005 to 0.18 wt%, Al: the balance, wherein RE is La and Ce with the proportion of 1: 2;
s2, analyzing the components of the aluminum liquid: transferring the smelted aluminum liquid to a holding furnace, uniformly stirring, sampling, performing component analysis, and detecting the contents of Al, Si, Fe, Cu, Mn, RE and Ti in the aluminum liquid;
s3, alloying treatment: controlling the temperature of the aluminum liquid in the heat preservation furnace to be 740 +/-10 ℃, adding aluminum-silicon alloy, aluminum-iron alloy, aluminum-copper alloy, aluminum-manganese alloy, aluminum-rare earth alloy and aluminum-titanium alloy into the furnace, and stirring to ensure that the aluminum liquid is uniform;
s4, refining: when the temperature of the aluminum liquid reaches 750 +/-10 ℃, introducing a refining agent into the aluminum liquid in the heat preservation furnace for refining;
s5, slagging off: after refining, heating the aluminum liquid, standing the melt for 5-10 minutes, opening a slagging-off door of a heat preservation furnace to carry out slagging-off when the temperature of the aluminum liquid is more than or equal to 730 ℃, and completely slagging off the scum on the surface of the aluminum liquid;
s6, component adjustment: sampling aluminum liquid from the furnace for component analysis, and confirming that the components of the aluminum liquid are as follows: si: 0.03 to 0.08 wt%, Fe: 0.25 to 0.40 wt%, Cu: 0.25 to 0.45 wt%, Mn: 0.75 to 0.95 wt%, Ti: 0.007-0.015 wt%, RE: 0.005-0.18 wt%; if the sampling result does not accord with the components, adjusting, and sampling and analyzing; if the sampling result meets the requirement, controlling the temperature of the aluminum liquid to be 740 +/-10 ℃, and blowing in the furnace and releasing;
s7, refining outside the furnace and deslagging: introducing the molten aluminum into an online degassing device and a filtering device in sequence, carrying out secondary refining, and degassing and deslagging again;
s8, continuous casting: continuously casting the molten aluminum refined again, wherein the casting temperature is 675-695 ℃, and the casting blank temperature on the approach bridge is 530-570 ℃;
s9, continuous rolling: continuously rolling the cast blank obtained by casting, wherein the rolling temperature is controlled to be 530-560 ℃, and the final rolling temperature is less than or equal to 300 ℃;
s10, annealing treatment: annealing the rolled aluminum material at 460-510 ℃ for 12 h.
2. The method of manufacturing a high-performance aluminum material as set forth in claim 1, wherein in step S1, an aluminum ingot having a purity of not less than 99.7% and AlSi are selected12、AlFe20、AlCu50、AlMn10、AlRE10And AlTi10The raw materials are used for mixing.
3. The method of manufacturing a high-performance aluminum material as set forth in claim 1, wherein in step S2, the temperature of the heat retention is 750 to 780 ℃.
4. The method for preparing the high-performance aluminum material as recited in claim 1, wherein in step S3, the aluminum liquid is sampled immediately after being stirred to be uniform, stokehole analysis is performed, feeding is determined according to the analysis result, the aluminum liquid component is controlled to reach a target value, and the sampling temperature is 740-760 ℃.
5. The method for preparing the high-performance aluminum material as claimed in claim 1, wherein in step S4, the refining agent is a powder injection refining agent, the amount of the refining agent is 0.4% of the total amount of the charging material, the carrier of the refining agent is high-purity nitrogen with the purity of 99.999%, the refining time is not less than 45 minutes, and the refining temperature is 750-780 ℃.
6. The method for preparing the high-performance aluminum material as claimed in claim 1, wherein in step S5, after the slag removal is completed, the aluminum liquid is allowed to stand in the heat preservation furnace for 30-40 minutes, and the temperature of the aluminum liquid is maintained at 740 ± 10 ℃.
7. A method for manufacturing an aluminum material with high performance as claimed in claim 1, wherein in the step S8, the casting process is performed by cooling around the casting billet by a steel strip and a U-shaped crystallization wheel, and the temperature of the cooling water is controlled to 25 ± 5 ℃.
8. The method for preparing the high-performance aluminum material as claimed in claim 1, wherein in step S10, the rolled aluminum material is protected by inert gas, and is placed in a well annealing furnace or a box annealing furnace for a complete annealing process, wherein the annealing temperature is 460-.
9. A high performance aluminum material prepared according to the method of any one of claims 1 to 8.
10. An air-conditioning connecting pipe, characterized in that the air-conditioning connecting pipe is prepared from the high-performance aluminum material of claim 9 by an extrusion molding process.
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| CN202010246989.XA CN111304475A (en) | 2020-03-31 | 2020-03-31 | High-performance aluminum material for air conditioner connecting pipe and preparation method thereof |
| PCT/CN2020/106701 WO2021196482A1 (en) | 2020-03-31 | 2020-08-04 | High-performance aluminum material for air conditioner connecting pipe and preparation method therefor |
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| CN112853165A (en) * | 2020-12-29 | 2021-05-28 | 淮安和通汽车零部件有限公司 | Highlight aluminum oxide profile for automobile exterior trimming parts and processing method thereof |
| WO2021196482A1 (en) * | 2020-03-31 | 2021-10-07 | 江苏亨通电力特种导线有限公司 | High-performance aluminum material for air conditioner connecting pipe and preparation method therefor |
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