CN110964957A - Cryogenic rolling and aging treatment process for high-strength Al-Zn-Mg alloy - Google Patents
Cryogenic rolling and aging treatment process for high-strength Al-Zn-Mg alloy Download PDFInfo
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- CN110964957A CN110964957A CN201911369229.1A CN201911369229A CN110964957A CN 110964957 A CN110964957 A CN 110964957A CN 201911369229 A CN201911369229 A CN 201911369229A CN 110964957 A CN110964957 A CN 110964957A
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- 239000000956 alloy Substances 0.000 title claims abstract description 40
- 229910045601 alloy Inorganic materials 0.000 title claims abstract description 39
- 238000005096 rolling process Methods 0.000 title claims abstract description 32
- 229910018571 Al—Zn—Mg Inorganic materials 0.000 title claims abstract description 30
- 230000032683 aging Effects 0.000 title claims abstract description 26
- 238000000034 method Methods 0.000 title claims abstract description 19
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 40
- 238000001816 cooling Methods 0.000 claims abstract description 22
- 239000007788 liquid Substances 0.000 claims abstract description 20
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 20
- 239000006104 solid solution Substances 0.000 claims abstract description 9
- 239000000243 solution Substances 0.000 claims description 10
- 239000000463 material Substances 0.000 claims description 7
- 238000004321 preservation Methods 0.000 claims description 6
- 238000010791 quenching Methods 0.000 claims description 4
- 230000000171 quenching effect Effects 0.000 claims description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 4
- 238000002360 preparation method Methods 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 claims 2
- 238000007654 immersion Methods 0.000 claims 1
- 230000000052 comparative effect Effects 0.000 description 10
- 238000001125 extrusion Methods 0.000 description 6
- 229910052802 copper Inorganic materials 0.000 description 3
- 238000005520 cutting process Methods 0.000 description 3
- 229910000838 Al alloy Inorganic materials 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 238000010587 phase diagram Methods 0.000 description 2
- 238000002791 soaking Methods 0.000 description 2
- 238000012876 topography Methods 0.000 description 2
- 238000005097 cold rolling Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000005098 hot rolling Methods 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
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- 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
- C22C21/10—Alloys based on aluminium with zinc as the next major constituent
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B3/00—Rolling materials of special alloys so far as the composition of the alloy requires or permits special rolling methods or sequences ; Rolling of aluminium, copper, zinc or other non-ferrous metals
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
- B21B45/0203—Cooling
- B21B45/0209—Cooling devices, e.g. using gaseous coolants
- B21B45/0215—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes
- B21B45/023—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes by immersion in a bath
-
- 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
- C22F1/053—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 zinc as the next major constituent
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B3/00—Rolling materials of special alloys so far as the composition of the alloy requires or permits special rolling methods or sequences ; Rolling of aluminium, copper, zinc or other non-ferrous metals
- B21B2003/001—Aluminium or its alloys
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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)
- Metal Rolling (AREA)
Abstract
A high-strength Al-Zn-Mg series alloy cryogenic rolling and aging treatment process belongs to the technical field of alloys. The method sequentially comprises the following steps: solid solution, liquid nitrogen cooling, cryogenic rolling and aging. The invention adjusts the structure of the sample by combining the deep cooling rolling and the aging, so that the sample obtains higher performance.
Description
Technical Field
The invention belongs to the technical field of metal material rolling, and particularly relates to a cryogenic rolling and aging treatment process for a high-strength Al-Zn-Mg alloy.
Background
The Al-Zn-Mg series aluminum alloy is widely applied to the fields of aerospace, rail transit, power energy and the like.
Al-Zn-Mg series aluminum alloy has poor plasticity, uneven deformation during processing, easy generation of serious shear bands, and easy generation of 45-degree-direction cracking at edges with large deformation. At present, Al-Zn-Mg series alloy is usually prepared by a hot rolling method, however, the prepared material has coarser crystal grains and lower strength, and the high-strength Al-Zn-Mg series alloy material is difficult to prepare.
The invention aims to provide a processing technology capable of improving the deformation capacity and the mechanical property of high-strength Al-Zn-Mg alloy.
Disclosure of Invention
The invention aims to provide a method for preparing a high-strength Al-Zn-Mg alloy by cryogenic rolling and aging treatment, so that the prepared material has higher mechanical comprehensive performance than a material prepared by cold rolling.
In order to achieve the purpose, the invention adopts the technical scheme that:
a deep cooling rolling and aging treatment preparation method of high-strength Al-Zn-Mg series alloy comprises the following steps:
the first step is as follows: solid solution
Carrying out solid solution treatment on the Al-Zn-Mg alloy strip to realize solid solution of main alloy elements;
the second step is that: liquid nitrogen cooling
Immersing the Al-Zn-Mg alloy subjected to solution treatment into liquid nitrogen for heat preservation;
the third step: rolling of
Rolling the Al-Zn-Mg alloy cooled in the second step, and cooling by liquid nitrogen every time;
the fourth step: aging
And carrying out aging treatment on the Al-Zn-Mg alloy rolled in the third step to obtain a high-strength Al-Zn-Mg alloy sample.
Further, the temperature of the first-step solution treatment is 450-;
and the second step of liquid nitrogen cooling, namely soaking the sample in liquid nitrogen to realize uniform cooling, wherein the temperature of the liquid nitrogen is-196 ℃, and the soaking time is 20-45 min.
And the third step of rolling is cryogenic rolling, the material is taken out from liquid nitrogen and immediately rolled at room temperature, the pass reduction is controlled to be 8-15%, the total deformation is not less than 50%, and the material is immersed in the liquid nitrogen for heat preservation for 3-8min in each pass.
And fourthly, controlling the aging treatment temperature to be 80-100 ℃, and keeping the temperature for 12-240 hours.
The technology of the invention is that the tissue of the sample is adjusted by combining cryogenic rolling and aging, so that the sample obtains higher performance. The sample subjected to cryogenic rolling can be subjected to larger deformation amount on the premise that the edge part does not crack. The sample prepared by deep cooling has uniform tissue and no obvious shear band. The strength of the sample after cryogenic rolling and aging treatment is improved to a certain extent compared with the strength of the sample after conventional T6 treatment. The strength of the Al-Zn-Mg alloy sample obtained by the invention is higher than that of a cold-rolled Al-Zn-Mg alloy sample, and the surface hardness of the Al-Zn-Mg alloy sample reaches 170 HV-230 HV.
Drawings
FIG. 1 is a side phase diagram of example 1;
FIG. 2 is a side golden phase diagram of comparative example 1;
FIG. 3 is a macro topography of the rolled plate of example 1;
FIG. 4 is a macro topography of the rolled sheet of comparative example 1;
FIGS. 1 and 2 are side metallographic images of alloys treated according to example 1 and comparative example 1 of the present invention. It can be seen from the graph that there is a significant difference in grain morphology between the two rolling processes, and there is no significant shear band observed on the side of the example 1 sample, and there is significant shear band on the side of the comparative example 1 sample. The rolling sample treated by the method is more uniform in deformation and has no obvious shear band; FIGS. 3 and 4 are views of macro-looking plates of alloys treated according to example 1 and comparative example 1 of the present invention. It can be seen from the figure that the edge of the sample of comparative example 1 is cracked already at 78% reduction, while the edge of the sample of example 1 is not cracked when the deformation reaches 90%, which shows that the rolled sample treated by the invention can be deformed more greatly without cracking at the edge.
Detailed Description
The present invention will be described in detail with reference to specific examples, but the present invention is not limited to the following examples
Example 1
The alloy comprises the following components in percentage by mass: zn: 5.6%, Mg: 2.1%, Cu: 1.2%, Er: 0.1%, Zr: 0.1 percent and the balance of Al.
The alloy is homogenized at 400 ℃/10h +465 ℃/24 h. And (3) extruding the cast ingot after homogenizing, wherein the extrusion temperature is 400 ℃, and the extrusion ratio is 15: 1. Cutting the extruded sample into plates with the size of 30mmx70mmx10mm, carrying out solid solution treatment on the plates, wherein the solid solution process is 470 ℃/2h, and quenching and cooling the plates by adopting water. And immersing the sample obtained after the solution treatment in liquid nitrogen for cooling for about 30 minutes, taking out the plate and rolling at room temperature, controlling the pass reduction at 10 percent and the total deformation at 91 percent, immersing the plate in the liquid nitrogen for heat preservation for about six minutes every time. And (3) carrying out aging treatment on the rolled sample, wherein the specific aging treatment process comprises the following steps: and taking the sample out of the liquid nitrogen, placing the sample in an oven with the oven temperature of 100 ℃ after about five minutes, preserving the temperature for 20 hours, and then cooling the sample in the air to the room temperature, and recording as a process I. Hardness and tensile properties of the samples were tested and the results are shown in table 1.
Comparative example 1
The alloy comprises the following components in percentage by mass: zn: 5.6%, Mg: 2.1%, Cu: 1.2%, Er: 0.1%, Zr: 0.1 percent and the balance of Al.
The alloy is homogenized at 400 ℃/10h +465 ℃/24 h. And (3) extruding the cast ingot after homogenizing, wherein the extrusion temperature is 400 ℃, and the extrusion ratio is 15: 1. Cutting the extruded sample into plates with the size of 30mmx70mmx10mm, carrying out solution treatment on the plates, wherein the solution treatment process is 470 ℃/2h, and quenching and cooling the plates by adopting water. Rolling the sample obtained after the solution treatment at room temperature, controlling the pass reduction at 10% and the total deformation at 78%, and carrying out aging treatment on the rolled sample, wherein the specific aging treatment process comprises the following steps: and (3) putting the sample into an oven with the oven temperature of 100 ℃, preserving the heat for 20 hours, and then cooling the sample to room temperature in air, and marking as a second process. Hardness and tensile properties of the samples were tested and the results are shown in table 1.
Comparative example 2
The alloy comprises the following components in percentage by mass: zn: 5.6%, Mg: 2.1%, Cu: 1.2%, Er: 0.1%, Zr: 0.1 percent and the balance of Al.
The alloy is homogenized at 400 ℃/10h +465 ℃/24 h. And (3) extruding the cast ingot after homogenizing, wherein the extrusion temperature is 400 ℃, and the extrusion ratio is 15: 1. Cutting the extruded sample into plates with the size of 10mmx10mmx5mm, carrying out solution treatment on the plates, wherein the solution treatment process is 470 ℃/2h, and quenching and cooling by adopting water. And (3) placing the mixture into an oven with the furnace temperature of 120 ℃, preserving the heat for 24 hours, and then cooling the mixture to room temperature in air, and recording as a third process. Hardness and tensile properties of the samples were tested and the results are shown in table 1.
Table 1 shows the mechanical test performance data of the samples of example 1, comparative example 1 and comparative example 2
According to the experimental results in the table 1, the alloy treated by the cryogenic rolling and the aging process has the advantages that the strength is improved by 36MPa, the tensile strength is improved by 44MPa, and the elongation is slightly reduced compared with the yield strength of the conventional T6 process. The yield strength of the deep cooling rolling and aging process treatment is improved by 47MPa, the tensile strength is improved by 35MPa, and the elongation is improved by 5.5% compared with the room temperature rolling and aging process. Therefore, the invention can not only enable the sample to have higher rolling reduction, but also enable the sample to have higher strength.
Claims (6)
1. A cryogenic rolling and aging treatment preparation method of a high-strength Al-Zn-Mg alloy is characterized by comprising the following steps:
the first step is as follows: solid solution
Carrying out solid solution treatment on the Al-Zn-Mg alloy strip to realize solid solution of main alloy elements;
the second step is that: liquid nitrogen cooling
Immersing the Al-Zn-Mg alloy subjected to solution treatment into liquid nitrogen for heat preservation;
the third step: rolling of
Rolling the Al-Zn-Mg alloy cooled in the second step, and cooling by liquid nitrogen every time;
the fourth step: aging
And carrying out aging treatment on the Al-Zn-Mg alloy rolled in the third step to obtain a high-strength Al-Zn-Mg alloy sample.
2. The method for preparing a high-strength Al-Zn-Mg alloy by cryogenic rolling and aging treatment according to claim 1, wherein the first solution treatment temperature is 450-500 ℃, the heat preservation time is 1.5-3 hours, and then quenching cooling is carried out by water.
3. The method for producing a high-strength Al-Zn-Mg alloy according to claim 1, wherein the second step of liquid nitrogen cooling is to immerse the sample in liquid nitrogen for uniform cooling, the temperature of the liquid nitrogen being-196 ℃ and the immersion time being 20-45 min.
4. The method for producing a high-strength Al-Zn-Mg alloy according to claim 1, wherein the third step of rolling is cryogenic rolling, the material is taken out from liquid nitrogen and immediately rolled at room temperature, the rolling reduction is controlled to 8 to 15% in each pass, the total deformation is not less than 50%, and the material is immersed in liquid nitrogen for 3 to 8min each pass.
5. The deep cooling rolling and aging treatment preparation method of the high-strength Al-Zn-Mg series alloy according to claim 1, characterized in that the temperature of the aging treatment in the fourth step is controlled to be 80-100 ℃, and the heat preservation time is 12-240 hours.
6. A high-strength Al-Zn-Mg-based alloy produced by the method according to any one of claims 1 to 5.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111926271A (en) * | 2020-08-31 | 2020-11-13 | 天津大学 | Processing method for improving in-plane isotropy of aluminum matrix composite |
| CN112048685A (en) * | 2020-09-14 | 2020-12-08 | 安徽鑫发铝业有限公司 | Post-treatment method capable of improving fatigue resistance of aluminum alloy |
| CN113714511A (en) * | 2021-09-23 | 2021-11-30 | 中南大学 | Heat treatment and cryogenic deformation composite process method for electric arc additive aluminum alloy component |
| CN115627374A (en) * | 2022-10-24 | 2023-01-20 | 江苏理工学院 | 7xxx high-strength aluminum alloy wire for electric arc welding and preparation method thereof |
| CN115846403A (en) * | 2022-09-23 | 2023-03-28 | 贵州大学 | Cobalt-based alloy with long rod-shaped phase structure with large number of stacking faults and deformation nanometer twin crystals and preparation method thereof |
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| CN106834985A (en) * | 2017-01-24 | 2017-06-13 | 湖南人文科技学院 | A kind of thermo-mechanical treatment process for significantly improving aluminium zinc magnesium alloy combination property |
| CN109457200A (en) * | 2018-12-11 | 2019-03-12 | 中南大学 | A kind of the deep cooling rolling and ageing treatment preparation method of high-performance aluminum lithium alloy band |
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2019
- 2019-12-26 CN CN201911369229.1A patent/CN110964957A/en active Pending
Patent Citations (4)
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| US5837070A (en) * | 1994-06-13 | 1998-11-17 | Pechiney Rhenalu | Aluminum-silicon alloy sheet for use in mechanical, aircraft and spacecraft construction |
| CN103343306A (en) * | 2013-07-17 | 2013-10-09 | 北京科技大学 | Treatment method for obviously improving deformability and mechanical property of high-strength aluminum alloy |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111926271A (en) * | 2020-08-31 | 2020-11-13 | 天津大学 | Processing method for improving in-plane isotropy of aluminum matrix composite |
| CN112048685A (en) * | 2020-09-14 | 2020-12-08 | 安徽鑫发铝业有限公司 | Post-treatment method capable of improving fatigue resistance of aluminum alloy |
| CN112048685B (en) * | 2020-09-14 | 2022-01-11 | 安徽鑫发铝业有限公司 | Post-treatment method capable of improving fatigue resistance of aluminum alloy |
| CN113714511A (en) * | 2021-09-23 | 2021-11-30 | 中南大学 | Heat treatment and cryogenic deformation composite process method for electric arc additive aluminum alloy component |
| CN115846403A (en) * | 2022-09-23 | 2023-03-28 | 贵州大学 | Cobalt-based alloy with long rod-shaped phase structure with large number of stacking faults and deformation nanometer twin crystals and preparation method thereof |
| CN115846403B (en) * | 2022-09-23 | 2023-08-15 | 贵州大学 | Cobalt-based alloy with long rod-shaped phase structure of a large number of stacking faults and deformation nanometer twin crystals and preparation method thereof |
| CN115627374A (en) * | 2022-10-24 | 2023-01-20 | 江苏理工学院 | 7xxx high-strength aluminum alloy wire for electric arc welding and preparation method thereof |
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