CN108994267A - It is a kind of to be able to ascend formability and the 6XXX system aluminium of ageing strengthening effect rolls plate preparation method - Google Patents
It is a kind of to be able to ascend formability and the 6XXX system aluminium of ageing strengthening effect rolls plate preparation method Download PDFInfo
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- CN108994267A CN108994267A CN201811167334.2A CN201811167334A CN108994267A CN 108994267 A CN108994267 A CN 108994267A CN 201811167334 A CN201811167334 A CN 201811167334A CN 108994267 A CN108994267 A CN 108994267A
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- 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
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/06—Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars
- B22D11/0622—Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars formed by two casting wheels
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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
- C21D9/0081—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for slabs; for billets
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- 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
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- C22C21/00—Alloys based on aluminium
- C22C21/02—Alloys based on aluminium with silicon as the next major constituent
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- 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
- C22F1/002—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working by rapid cooling or quenching; cooling agents used therefor
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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
- 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
- C22F1/043—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 of alloys with silicon as the next major constituent
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Abstract
The invention discloses a kind of 6XXX system aluminium for being able to ascend formability and ageing strengthening effect to roll plate preparation method, comprising: Step 1: preparation 6XXX line aluminium alloy melt；Wherein, the ingredient of the 6XXX line aluminium alloy melt are as follows: it be the mass fraction of 0.10-1.0%, Cu be the mass fraction of 0.01-0.15%, Mn be the mass fraction of 0.01-0.15%, Mg is 0.40-0.90% that the mass fraction of Si, which is the mass fraction of 1.0-1.6%, Fe, and surplus is Al and impurity；Sub realizable fuzzy matrix is carried out Step 2: 6XXX line aluminium alloy melt is drained into high thermal conductivity water cooling casting roller gap, obtains high solid solution 6XXX line aluminium alloy cast-rolled strip；Step 3: carrying out multi-pass to the high solid solution 6XXX line aluminium alloy cast-rolled strip is cold-rolled to specific thickness, cold-rolled aluminum alloy sheet is obtained；Step 4: being quenched after carrying out solution heat treatment to the cold-rolled aluminum alloy sheet, T4 state 6XXX line aluminium alloy cold-reduced sheet is obtained.6XXX system provided by the invention aluminium rolls plate preparation method, is able to ascend the formability and ageing strengthening effect of 6XXX line aluminium alloy cold-reduced sheet.
Description
Technical field
The invention belongs to aluminium to roll plate preparation technical field, in particular to one kind is able to ascend formability and ageing strengthening
The 6XXX system aluminium of effect rolls plate preparation method.
Background technique
Energy problem of the world today, problem of environmental pollution are increasingly serious, and automotive light weight technology is trend of the times.Mitigate vehicle body certainly
Weight can be such that vehicle develops towards low power consuming, low emission and efficient direction, to realize the target of energy-saving and environmental protection.In addition,
The mechanical property of promotion vehicle body is also the eternal pursuit for safety grounds.Aluminium alloy have light weight, corrosion-resistant, specific strength and
The advantages that specific stiffness is high, and formability is good, is easily recycled；Therefore, aluminium alloy becomes the ideal material of automobile lightweight.
6XXX line aluminium alloy is heat-treatable strengthened alloy, has preferable forming property under T4 state, while under T6 state again
Intensity with higher, thus 6XXX line aluminium alloy is considered as the body of a motor car material of most prospect.Currently, 6XXX system aluminium closes
Gold has started the manufacture for being applied to the large-scale car body structural member such as car panel, especially hood, car door and roof.
Entitled a kind of patent of the preparation method of 6022 aluminum alloy plate materials that number of patent application is 201611006519.6
Technology is prepared for 6022 aluminium using cast-rolled strip heating-hot rolling-intermediate annealing-cold rolling-solid solution-preageing technique and closes
Gold, compared to existing old process, although this method eliminates homogenization process, but still remains that cast-rolled strip heating, centre moves back
Firer's sequence, therefore either energy cost or production time need to be further decreased.In addition, 6022 aluminium of this method preparation
Alloy is higher in T4 state lower yield strength, has reached 130MPa or more, and under T6 state 6022 aluminium alloys yield strength
It is lower, average out to 170MPa.Therefore, 6022 aluminium alloys which obtains shape performance and ageing strengthening effect simultaneously
It is unoutstanding.
The entitled Large strain intensified index AlMgSi sheet alloy and its system that number of patent application is 201310721694.3
The patented technology of Preparation Method, using casting-homogenization heat treatment-hot rolling-once cold rolling-secondary cold-rolling-solution treatment
Technique is prepared for 6XXX line aluminium alloy.The patent is equally based on conventional manufacturing procedures, and high production cost, period are long.Meanwhile the system
The 6XXX line aluminium alloy that Preparation Method obtains is higher in T4 state lower yield strength, has reached 136MPa, it is seen that the forming of the material
Performance is not also outstanding.
Number of patent application be 201480010356.1 entitled room-temperature aging after excellent aluminium alloy plate it is special
Sharp technology, using casting-homogenization heat treatment-hot rolling-intermediate annealing-cold rolling-solid solution-preageing common process stream
Journey increases the Sn element of 0.01-0.3% in chemical component, surrenders under prepared 6XXX line aluminium alloy T4 state strong
Degree is lower than 100MPa, and after the processing of T6 artificial aging, the yield strength increment of 6XXX line aluminium alloy is higher than 90MPa.As it can be seen that should
The material of patented technology preparation has excellent forming property and age-hardening effect.The disadvantage is that it still is based on old process, and
And alloying element Sn is increased, high production cost, duty cycle are long.
Existing patented technology is based primarily upon old process, and high production cost, period are long, and the 6XXX system aluminium prepared closes
Golden forming property and age-hardening effect simultaneously do not have significant advantage.
Summary of the invention
The present invention provides a kind of 6XXX system aluminium for being able to ascend formability and ageing strengthening effect to roll plate preparation side
Method comprising three Sub realizable fuzzy matrix, cold rolling and solution treatment process procedures；An object of the present invention is to improve 6XXX system aluminium
It rolls plate and shapes performance and ageing strengthening effect in T4 state.
The present invention provides a kind of 6XXX system aluminium for being able to ascend formability and ageing strengthening effect to roll plate preparation side
Method, that eliminates cast-rolled strip homogenization and hot rolling links；The preparation work of plate is rolled the second object of the present invention is to optimize 6XXX system aluminium
Skill shortens process flow.
Technical solution provided by the invention are as follows:
It is a kind of to be able to ascend formability and the 6XXX system aluminium of ageing strengthening effect rolls plate preparation method, including walk as follows
It is rapid:
Step 1: preparation 6XXX line aluminium alloy melt；
Wherein, the ingredient of the 6XXX line aluminium alloy melt are as follows: the mass fraction of Si is the quality point of 1.0-1.6%, Fe
It is the mass fraction of 0.01-0.15%, Mn is the quality point of 0.01-0.15%, Mg that number, which is the mass fraction of 0.10-1.0%, Cu,
Number is 0.40-0.90%, and surplus is Al and impurity；
Sub realizable fuzzy matrix is carried out Step 2: 6XXX line aluminium alloy melt is drained into water cooling casting roller gap, obtains height
It is dissolved 6XXX line aluminium alloy cast-rolled strip；
Step 3: carrying out multi-pass to the high solid solution 6XXX line aluminium alloy cast-rolled strip is cold-rolled to specific thickness, aluminium is obtained
Alloy cold-reduced sheet；
Step 4: being quenched after carrying out solution heat treatment to the cold-rolled aluminum alloy sheet, T4 state 6XXX is obtained
Line aluminium alloy cold-reduced sheet.
Preferably, in said step 1,6XXX line aluminium alloy melt is prepared, is included the following steps:
Step 1, under protection of argon gas, obtains melt in 750-800 DEG C of fusing for business fine aluminium；
Step 2 carries out scarfing cinder processing to the melt, and in 680-720 DEG C of range inside holding；
Step 3 is de-gassed, after refining treatment, and Al-Si alloy, Al- are separately added into 680-720 DEG C of temperature range
Mn alloy, made of Al-Cu alloy and pure Fe powder, heat preservation；
Step 4 is de-gassed, after refining treatment, and pure Mg powder is added in 680-720 DEG C of temperature range, and heat preservation 10-15 divides
Clock obtains 6XXX line aluminium alloy melt.
Preferably, in the step 2, water cooling Casting Roller is hard alloy steel material, and surface is coated with high thermal conductivity
Copper roller set, the water cooling Casting Roller inside are configured with circulating water cooling system.
Preferably, in the step 3, multiple cold rolling is carried out to height solid solution 6XXX line aluminium alloy cast-rolled strip, including such as
Lower step:
Step 1 carries out the heavy reduction rate cold rolling of 2-4 passage to the 6XXX line aluminium alloy cast-rolled strip with the first mill speed,
Every single pass reduction ratio is 20%-25%；
Step 2 carries out the small reduction ratio cold rolling of 3-5 passage with the second mill speed, and every single pass reduction ratio is 10%-
15%.
Preferably, first mill speed is less than 10 ms/min；Second mill speed is 10-20 ms/min
Clock.
Preferably, in the step 4, using the side of continuous solution annealing processing or bell furnace solution annealing processing
Method carries out solution heat treatment to cold-rolled aluminum alloy sheet.
Preferably, the temperature of the solution heat treatment is 480-580 DEG C, soaking time 10-120min.
Preferably, the method for the solution heat treatment are as follows:
Cold-rolled aluminum alloy sheet is heated to 480-520 DEG C, keeps the temperature 5-60 minutes；Continue to be heated to 550-580 DEG C, keeps the temperature 5-
60 minutes.
Preferably, which is characterized in that in the step 4, using water as hardening media.
It preferably, further include removing height solid solution 6XXX line aluminium alloy cast-rolled strip cutting head milling face before the step 3
Go surface defect.
The beneficial effects of the present invention are:
(1) provided by the invention to be able to ascend formability and the 6XXX system aluminium of ageing strengthening effect rolls plate preparation side
Method, including three Sub realizable fuzzy matrix, cold rolling and solution treatment process procedures, the 6XXX line aluminium alloy of preparation are strong in T4 state yield
Degree is not higher than 100MPa, and uniform elongation is not less than 25%, and forming property is excellent；In further stamping deep processing and ageing treatment
Afterwards, i.e., it is not less than 220MPa in the yield strength of T6 state 6XXX line aluminium alloy, meets the requirement of resistance to deformation, this method
The 6XXX line aluminium alloy of preparation has good age-hardening effect.
(2) provided by the invention to be able to ascend formability and the 6XXX system aluminium of ageing strengthening effect rolls plate preparation side
Method eliminates slab homogenization and hot rolling link, significantly shortens process flow；Greatly reduce energy consumption and gas row
It puts.
Detailed description of the invention
Fig. 1 is the electron microscope of the aluminium alloy casting state tissue prepared in embodiment 1.
Fig. 2 is the electron microscope of the aluminium alloy casting state tissue of comparative example preparation.
Fig. 3 is 6XXX line aluminium alloy prepared by embodiment 1 and 6XXX line aluminium alloy cold-reduced sheet prepared by comparative example in T4 shape
Mechanical property comparison diagram under state.
Fig. 4 is 6XXX line aluminium alloy prepared by embodiment 1 and 6XXX line aluminium alloy cold-reduced sheet prepared by comparative example in T6 shape
Mechanical property comparison diagram under state.
Specific embodiment
Present invention will be described in further detail below with reference to the accompanying drawings, to enable those skilled in the art referring to specification text
Word can be implemented accordingly.
The present invention provides a kind of 6XXX system aluminium for being able to ascend formability and ageing strengthening effect to roll plate preparation side
Method mainly includes three Sub realizable fuzzy matrix, cold rolling and solution treatment process procedures, and specific preparation process is as follows:
Step 1: preparation 6XXX line aluminium alloy melt, specifically comprises the following steps:
(1) under argon atmosphere, business fine aluminium is obtained into melt in 750-800 DEG C of fusing；
(2) scarfing cinder processing is carried out to the melt, and temperature adjustment is small in 680-720 DEG C of range inside holding 2
When keep melt temperature uniform；
(3) it is de-gassed, after refining treatment, is separately added into Al-Si, Al-Mn, Al-Cu in 680-720 DEG C of temperature range
Equal intermediate alloys and pure Fe powder keep the temperature 1 hour；
(4) after carrying out secondary degassing, refining treatment, pure Mg powder is added in 680-720 DEG C of temperature range, keeps the temperature 10-15
Minute obtains 6XXX line aluminium alloy melt；
In above-mentioned preparation process, the amount of intermediate alloy, pure Fe powder and pure Mg powder is added by control, makes 6XXX obtained
The ingredient of line aluminium alloy melt are as follows: the mass fraction of Si is that the mass fraction of 1.0-1.6%, Fe are the matter of 0.10-1.0%, Cu
Measuring the mass fraction that the mass fraction that score is 0.01-0.15%, Mn is 0.01-0.15%, Mg is 0.40-0.90%, surplus
For Al and inevitable impurity.
Step 2: carrying out Sub realizable fuzzy matrix to 6XXX line aluminium alloy melt, high solid solution 6XXX line aluminium alloy cast-rolled strip is obtained；
Method particularly includes:
By 6XXX line aluminium alloy melt transfer obtained in step 1 into the tundish through overbaking, later via crystallization
Device running channel drains into vertical arrangement or horizontally disposed, diameter is identical and water cooling casting roller gap that reversely rotate at the same speed in, obtain
Obtain high solid solution 6XXX line aluminium alloy cast-rolled strip.
Wherein, the water cooling Casting Roller uses hard alloy steel material, and surface is coated with high heat-conducting copper roller set, casting
Circulating water cooling system is configured with inside roller, meanwhile, to Casting Roller table during carrying out Sub realizable fuzzy matrix to aluminium alloy melt
Face carries out water spray or aerosol is cooling, it is made to keep lower temperature.
6XXX line aluminium alloy melt cooling rate in water cooling casting roller gap reaches 80 DEG C/s or more, belongs to Sub realizable fuzzy matrix
Range.
In conventional coagulation process flow, aluminium alloy cooling velocity is slower, typically about 10 DEG C/s or so；Since melt is cold
But speed is slow, and slab is easy to produce microsegregation and gross segregation, and the eutectic phase group that forming quantity is more, size is coarseer
It knits.6XXX line aluminium alloy chemical component and nonuniform organization can seriously affect the forming property etc. of finished product.In order to promote 6XXX
Line aluminium alloy chemical component and structural homogenity generally require to carry out slab homogenization heat treatment, homogenize heat treatment temperature
Generally greater than 500 DEG C, heat preservation is several to arrive dozens of hour, energy consumption has been significantly greatly increased, and extend the production cycle, Wu Fashi
Existing low cost, efficient and greenization production.Using Sub realizable fuzzy matrix technology, melt cooling rate, a side can be greatly improved
Face can inhibit the segregation and precipitation of solute atoms in process of setting, to eliminate or alleviate segregation phenomena；On the other hand, it mentions
After high cooldown rate, the eutectic phase amount in cast-rolled strip is reduced, size reduces, and primary dendrite suspension, fragmentation realize Gao Gu
Molten solidified structure refinement.The present invention is using high thermal conductivity water cooling or the cooling copper sheathing Casting Roller of aerosol to melted 6XXX line aluminium alloy
Melt carries out the high solid solution cast-rolled strip of Sub realizable fuzzy matrix preparation, and cooling rate is not less than 80 DEG C/s during solidifying since being poured into.
By Sub realizable fuzzy matrix, chemical component and the uniform high solid solution cast-rolled strip of microstructure are obtained, can be saved at homogenization heat
Reason and hot-rolled process, shorten process flow, greatly reduce production cost, shorten the production cycle, realize it is efficient, low at
This and greenization produce.
Preferably, by height solid solution cast-rolled strip thickness control in 3-15mm, to reach higher cooling rate.
Step 3: carrying out multi-pass to the high solid solution 6XXX line aluminium alloy cast-rolled strip is cold-rolled to specific thickness, aluminium is obtained
Alloy cold-reduced sheet；Specific step is as follows:
(1) high solid solution 6XXX line aluminium alloy cast-rolled strip obtained in step 2 is cut off into milling face, removes surface defect；
(2) it will be dissolved 6XXX line aluminium alloy cast-rolled strip by the high of cutting head milling face, in roll rotational speed less than 10 ms/min
In the case of, to the heavy reduction rate cold rolling of 2-4 passage is carried out, every single pass reduction ratio is 20%-25%, makes 6XXX line aluminium alloy cold rolling
Plate thickness is quickly thinned；
(3) at 10-20 ms/min of roll rotational speed, the small reduction ratio cold rolling of 3-5 passage, every single pass pressure are carried out
Rate is 10%-15%, refines 6XXX line aluminium alloy cold-reduced sheet crystallite dimension further；
The 6XXX line aluminium alloy cold-reduced sheet that total reduction is greater than 70% is obtained after above-mentioned multi-pass cold rolling.
Step 4: being quenched after carrying out solution heat treatment to the 6XXX line aluminium alloy cold-reduced sheet, T4 shape is obtained
State 6XXX line aluminium alloy cold-reduced sheet；
6XXX line aluminium alloy cold-reduced sheet can be carried out using continuous solution annealing processing or bell furnace solution annealing processing
Solution heat treatment；Solution heat treatment temperature is 480-580 DEG C, soaking time 10-120min；Later, solution heat treatment will be passed through
The 6XXX line aluminium alloy cold-reduced sheet of reason is quenched, and hardening media is water, obtains T4 state 6XXX line aluminium alloy cold-reduced sheet.
In another embodiment, according to last phase Precipitation Temperature difference in 6XXX line aluminium alloy cold-reduced sheet, using low temperature-height
Warm heat treatment mode stage by stage: being first heated to 480-520 DEG C of low temperature section, keeps the temperature 5-60 minutes, keeps Precipitation Temperature lower
Last phase is solid-solution in matrix；It is again heated to 550-580 DEG C of high-temperature section, 5-60 minutes is kept the temperature, keeps Precipitation Temperature higher residual
Remaining phase is solid-solution in matrix, then quick water hardening, forms supersaturated solid solution.
6XXX line aluminium alloy cold rolling microstructure prepared by the present invention, on the one hand due to the heredity refinement of Sub realizable fuzzy matrix tissue
Characteristic has tiny, disperse educt phase, facilitates sufficiently molten when solution treatment on the other hand due to being regulated and controled by multi-pass cold rolling
Solution is in aluminum substrate.Therefore, T4 state 6XXX line aluminium alloy cold-reduced sheet, tissue in residual precipitated phase it is less, have it is lower bend
Intensity (≤100MPa), good uniform elongation (>=25%) are taken, forming property is excellent, can meet adding for different shape product
Work demand.After further stamping deep processing and 170 DEG C, the aging strengthening model of 30min, i.e., in T6 state 6XXX line aluminium alloy
Yield strength is not less than 220MPa, meets the requirement of resistance to deformation, it is seen that the 6XXX line aluminium alloy of this method preparation has
Good age-hardening effect.
Embodiment 1
Prepare 6XXX line aluminium alloy melt, the ingredient (mass fraction) for the 6XXX line aluminium alloy melt being prepared are as follows: Si
1.1%, Fe 0.1%, Cu 0.05%, Mn 0.05%, Mg 0.8%, surplus are Al and inevitable impurity；By 6XXX system
Aluminium alloy melt carries out Sub realizable fuzzy matrix, then, carries out cold rolling after eliminating defect to cast-rolled strip, carries out solution treatment after cold rolling.
Specific process parameter is shown in Table 1, and 6XXX line aluminium alloy T4 state performance obtained is shown in Table 2.Artificial aging (170 is carried out to aluminium alloy
DEG C, 30min) processing is to simulate downstream process, and (yield strength increases for 6XXX line aluminium alloy T6 state performance and timeliness hardening effect
Amount) it is shown in Table 2.
Embodiment 2
Prepare 6XXX line aluminium alloy melt, the ingredient (mass fraction) for the 6XXX line aluminium alloy melt being prepared are as follows: Si
1.3%, Fe 0.35%, Cu 0.01%, Mn 0.15%, Mg 0.65%, surplus are Al and inevitable impurity.By 6XXX
Line aluminium alloy melt carries out Sub realizable fuzzy matrix, carries out cold rolling after then eliminating defect to cast-rolled strip, carries out solution treatment after cold rolling.
Specific process parameter is shown in Table 1,6XXX line aluminium alloy T4 state performance and is shown in Table 2.To aluminium alloy carry out artificial aging (170 DEG C,
30min) to simulate downstream process, 6XXX line aluminium alloy T6 state performance and timeliness hardening effect (yield strength increment) are shown in for processing
Table 2.
Embodiment 3
Prepare 6XXX line aluminium alloy melt, the ingredient (mass fraction) for the 6XXX line aluminium alloy melt being prepared are as follows: Si
1.6%, Fe 0.13%, Cu 0.15%, Mn 0.01%, Mg 0.40%, surplus are Al and inevitable impurity.By 6XXX
Aluminium alloy melt carries out Sub realizable fuzzy matrix, carries out cold rolling after then eliminating defect to cast-rolled strip, carries out solution treatment after cold rolling.Tool
Body technology parameter is shown in Table 1,6XXX line aluminium alloy T4 state performance and is shown in Table 2.Artificial aging (170 DEG C, 30min) are carried out to aluminium alloy
To simulate downstream process, 6XXX line aluminium alloy T6 state performance and timeliness hardening effect (yield strength increment) are shown in Table 2 for processing.
Embodiment 4
Prepare 6XXX line aluminium alloy melt, the ingredient (mass fraction) for the 6XXX line aluminium alloy melt being prepared are as follows: Si
1.5%, Fe 1.0%, Cu 0.10%, Mn 0.03%, Mg 0.52%, surplus are Al and inevitable impurity.By melting
Good 6XXX aluminium alloy melt carries out Sub realizable fuzzy matrix, carries out cold rolling after then eliminating defect to cast-rolled strip, is consolidated after cold rolling
Molten processing.Specific process parameter is shown in Table 1,6XXX line aluminium alloy T4 state performance and is shown in Table 2.Artificial aging (170 is carried out to aluminium alloy
DEG C, 30min) processing is to simulate downstream process, and (yield strength increases for 6XXX line aluminium alloy T6 state performance and timeliness hardening effect
Amount) it is shown in Table 2.
Embodiment 5
Prepare 6XXX line aluminium alloy melt, the ingredient (mass fraction) for the 6XXX line aluminium alloy melt being prepared are as follows: Si
1.3%, Fe 0.7%, Cu 0.08%, Mn 0.11%, Mg 0.63%, surplus are Al and inevitable impurity.By 6XXX
Aluminium alloy melt carries out Sub realizable fuzzy matrix, carries out cold rolling after then eliminating defect to cast-rolled strip, carries out solution treatment after cold rolling.Tool
Body technology parameter is shown in Table 1,6XXX line aluminium alloy T4 state performance and is shown in Table 2.Artificial aging (170 DEG C, 30min) are carried out to aluminium alloy
To simulate downstream process, 6XXX line aluminium alloy T6 state performance and timeliness hardening effect (yield strength increment) are shown in Table 2 for processing.
Embodiment 6
Prepare 6XXX line aluminium alloy melt, the ingredient (mass fraction) for the 6XXX line aluminium alloy melt being prepared are as follows: Si
1.4%, Fe 0.4%, Cu 0.01%, Mn 0.05%, Mg 0.75%, surplus are Al and inevitable impurity.By 6XXX
Aluminium alloy melt carries out Sub realizable fuzzy matrix, carries out cold rolling after then eliminating defect to cast-rolled strip, carries out solution treatment after cold rolling.Tool
Body technology parameter is shown in Table 1,6XXX line aluminium alloy T4 state performance and is shown in Table 2.Artificial aging (170 DEG C, 30min) are carried out to aluminium alloy
To simulate downstream process, 6XXX line aluminium alloy T6 state performance and timeliness hardening effect (yield strength increment) are shown in Table 2 for processing.
Embodiment 7
Prepare 6XXX line aluminium alloy melt, the ingredient (mass fraction) for the 6XXX line aluminium alloy melt being prepared are as follows: Si
1.2%, Fe 0.15%, Cu 0.05%, Mn 0.07%, Mg 0.68%, surplus are Al and inevitable impurity.By 6XXX
Aluminium alloy melt carries out Sub realizable fuzzy matrix, carries out cold rolling after then eliminating defect to cast-rolled strip, carries out solution treatment after cold rolling.Tool
Body technology parameter is shown in Table 1,6XXX line aluminium alloy T4 state performance and is shown in Table 2.Artificial aging (170 DEG C, 30min) are carried out to aluminium alloy
To simulate downstream process, 6XXX line aluminium alloy T6 state performance and timeliness hardening effect (yield strength increment) are shown in Table 2 for processing.
Embodiment 8
Prepare 6XXX line aluminium alloy melt, the ingredient (mass fraction) for the 6XXX line aluminium alloy melt being prepared are as follows: Si
1.4%, Fe 0.60%, Cu 0.13%, Mn 0.11%, Mg 0.88%, surplus are Al and inevitable impurity.By 6XXX
Aluminium alloy melt carries out Sub realizable fuzzy matrix, carries out cold rolling after then eliminating defect to cast-rolled strip, carries out solution treatment after cold rolling.Tool
Body technology parameter is shown in Table 1,6XXX line aluminium alloy T4 state performance and is shown in Table 2.Artificial aging (170 DEG C, 30min) are carried out to aluminium alloy
To simulate downstream process, 6XXX line aluminium alloy T6 state performance and timeliness hardening effect (yield strength increment) are shown in Table 2 for processing.
Comparative example
6XXX line aluminium alloy melt is prepared, the ingredient that aluminium obtained closes melt is same as Example 1, i.e. 6XXX line aluminium alloy
The ingredient (mass fraction) of melt are as follows: Si 1.1%, Fe 0.1%, Cu 0.05%, Mn 0.05%, Mg 0.8%, surplus are
Al and inevitable impurity；6XXX line aluminium alloy melt is subjected to conventional coagulation, 10 DEG C/s of cooling velocity, then, to slab
Homogenization Treatments are carried out after eliminating defect, 550 DEG C of homogenization temperature, keep the temperature 120min.Slab after homogenization is subjected to cold rolling,
Solution treatment is carried out after cold rolling.Specific process parameter is shown in Table 1, and 6XXX line aluminium alloy T4 state performance obtained is shown in Table 2.Aluminium is closed
Gold carries out (170 DEG C, 30min) of artificial aging processing to simulate downstream process, and 6XXX line aluminium alloy T6 state performance and timeliness are hard
Change effect (yield strength increment) and is shown in Table 2.
1 embodiment technological parameter of table
2 6XXX system aluminium of table rolls plate performance
It can be seen that by embodiment 1-8 and be able to ascend formability and ageing strengthening effect using provided by the invention
The 6XXX system aluminium of fruit roll plate preparation method preparation T4 state 6XXX line aluminium alloy cold-reduced sheet, have lower yield strength (<
100MPa), good uniform elongation (> 25%), forming property is excellent, can meet the process requirements of different shape product.?
Further stamping deep processing and 170 DEG C, after the aging strengthening model of 30min, i.e., the yield strength in T6 state 6XXX line aluminium alloy
Not less than 220MPa, meet the requirement of resistance to deformation.
As shown in Figs. 1-2, the aluminium of aluminium alloy casting state tissue and comparative example (common process) preparation prepared in embodiment 1
Alloy casting state tissue is compared, and either crystallite dimension or Models For Secondary Dendrite Arm spacing obviously refines.
As shown in Figure 3-4, the 6XXX system that will be prepared in the 6XXX line aluminium alloy cold-reduced sheet and comparative example that are prepared in embodiment 1
Cold-rolled aluminum alloy sheet carries out mechanical property comparison, and under T4 state, the 6XXX line aluminium alloy cold-reduced sheet for preparing in embodiment 1 is bent
Taking intensity is only 85MPa, and uniform elongation reaches 28.5%, has preferable forming property；Old process work is used in comparative example
The cold-rolled aluminum alloy sheet of skill preparation is 113MPa in the yield strength of T4 state, and uniform elongation only has 20%；Under T6 state,
The yield strength of the 6XXX line aluminium alloy cold-reduced sheet prepared in embodiment 1 is 247MPa, yield strength increment 162MPa；Comparison
The yield strength of the 6XXX line aluminium alloy cold-reduced sheet prepared in example is 238MPa, yield strength increment 125MPa；As it can be seen that opposite
In common process, in T4 state, the 6XXX line aluminium alloy cold-reduced sheet prepared using preparation method provided by the invention is processed into
Shape is more preferable；6XXX aluminium alloy prepared by the present invention has excellent forming property and age-hardening effect simultaneously.
Although the embodiments of the present invention have been disclosed as above, but its is not only in the description and the implementation listed
With it can be fully applied to various fields suitable for the present invention, for those skilled in the art, can be easily
Realize other modification, therefore without departing from the general concept defined in the claims and the equivalent scope, the present invention is simultaneously unlimited
In specific details and legend shown and described herein.
Claims (10)
- Formability is able to ascend and the 6XXX system aluminium of ageing strengthening effect rolls plate preparation method 1. a kind of, which is characterized in that Include the following steps:Step 1: preparation 6XXX line aluminium alloy melt；Wherein, the ingredient of the 6XXX line aluminium alloy melt are as follows: the mass fraction of Si is that the mass fraction of 1.0-1.6%, Fe are The mass fraction of 0.10-1.0%, Cu are that the mass fraction of 0.01-0.15%, Mn are that the mass fraction of 0.01-0.15%, Mg is 0.40-0.90%, surplus are Al and impurity；Sub realizable fuzzy matrix is carried out Step 2: 6XXX line aluminium alloy melt is drained into water cooling casting roller gap, obtains high solid solution 6XXX line aluminium alloy cast-rolled strip；Step 3: carrying out multi-pass to the high solid solution 6XXX line aluminium alloy cast-rolled strip is cold-rolled to specific thickness, aluminium alloy is obtained Cold-reduced sheet；Step 4: being quenched after carrying out solution heat treatment to the cold-rolled aluminum alloy sheet, T4 state 6XXX system aluminium is obtained Alloy cold-reduced sheet.
- Formability is able to ascend and the 6XXX system aluminium of ageing strengthening effect rolls plate preparation side 2. according to claim 1 Method, which is characterized in that in said step 1, prepare 6XXX line aluminium alloy melt, include the following steps:Step 1, under protection of argon gas, obtains melt in 750-800 DEG C of fusing for business fine aluminium；Step 2 carries out scarfing cinder processing to the melt, and in 680-720 DEG C of range inside holding；Step 3 is de-gassed, after refining treatment, Al-Si alloy is separately added into 680-720 DEG C of temperature range, Al-Mn is closed Gold, made of Al-Cu alloy and pure Fe powder, heat preservation；Step 4 is de-gassed, after refining treatment, and pure Mg powder is added in 680-720 DEG C of temperature range, keeps the temperature 10-15 minutes, Obtain 6XXX line aluminium alloy melt.
- Formability is able to ascend and the 6XXX system aluminium of ageing strengthening effect rolls plate system 3. according to claim 1 or 2 Preparation Method, which is characterized in that in the step 2, water cooling Casting Roller is hard alloy steel material, and surface is coated with height and leads Hot copper roller set, the water cooling Casting Roller inside are configured with circulating water cooling system.
- Formability is able to ascend and the 6XXX system aluminium of ageing strengthening effect rolls plate preparation side 4. according to claim 3 Method, which is characterized in that in the step 3, multiple cold rolling is carried out to height solid solution 6XXX line aluminium alloy cast-rolled strip, including as follows Step:Step 1 carries out the heavy reduction rate cold rolling of 2-4 passage, every list to the 6XXX line aluminium alloy cast-rolled strip with the first mill speed Percentage pass reduction is 20%-25%；Step 2 carries out the small reduction ratio cold rolling of 3-5 passage with the second mill speed, and every single pass reduction ratio is 10%-15%.
- Formability is able to ascend and the 6XXX system aluminium of ageing strengthening effect rolls plate preparation side 5. according to claim 4 Method, which is characterized in that first mill speed is less than 10 ms/min；Second mill speed is 10-20 ms/min.
- 6. the 6XXX system aluminium for being able to ascend formability and ageing strengthening effect according to claim 1 or 5 rolls plate system Preparation Method, which is characterized in that in the step 4, using the side of continuous solution annealing processing or bell furnace solution annealing processing Method carries out solution heat treatment to cold-rolled aluminum alloy sheet.
- Formability is able to ascend and the 6XXX system aluminium of ageing strengthening effect rolls plate preparation side 7. according to claim 6 Method, which is characterized in that the temperature of the solution heat treatment is 480-580 DEG C, soaking time 10-120min.
- Formability is able to ascend and the 6XXX system aluminium of ageing strengthening effect rolls plate preparation side 8. according to claim 7 Method, which is characterized in that the method for the solution heat treatment are as follows:Cold-rolled aluminum alloy sheet is heated to 480-520 DEG C, keeps the temperature 5-60 minutes；Continue to be heated to 550-580 DEG C, 5-60 points of heat preservation Clock.
- Formability is able to ascend and the 6XXX system aluminium of ageing strengthening effect rolls plate preparation side 9. according to claim 1 Method, which is characterized in that in the step 4, using water as hardening media.
- 10. the 6XXX system aluminium for being able to ascend formability and ageing strengthening effect according to claim 1 or described in 9 rolls plate system Preparation Method, which is characterized in that further include removing height solid solution 6XXX line aluminium alloy cast-rolled strip cutting head milling face before the step 3 Go surface defect.
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| CN111761036A (en) * | 2020-07-08 | 2020-10-13 | 甘肃东兴铝业有限公司 | Casting and rolling method for 6xxx series aluminum alloy plate for automobile |
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