CN110093543B

CN110093543B - Goss + Cube or P + Cube texture aluminum alloy with excellent fracture toughness and preparation method thereof

Info

Publication number: CN110093543B
Application number: CN201910380144.7A
Authority: CN
Inventors: 赵齐; 刘志义
Original assignee: Hubei University of Automotive Technology
Current assignee: Hubei University of Automotive Technology
Priority date: 2019-05-08
Filing date: 2019-05-08
Publication date: 2021-04-20
Anticipated expiration: 2039-05-08
Also published as: CN110093543A

Abstract

The invention provides a Goss + Cube or P + Cube texture aluminum alloy with excellent fracture toughness and a preparation method thereof, wherein the aluminum alloy comprises the following components, by mass, 3.5-4.2% of Cu, 1.0-1.5% of Mg, 0.1-0.28% of Zr, 0.05-0.7% of Mn, 0.02-0.09% of Ti, 0.06% of Fe, 0.06% of Si, and the balance of Al; the sum of the mass percentages of the components is 100 percent. The preparation method comprises the steps of carrying out first long-time solid solution, water quenching and artificial aging treatment on an aluminum alloy plate containing specific components, then carrying out high-temperature medium-large deformation hot rolling, then carrying out recrystallization annealing treatment, and finally carrying out solid solution, water quenching and natural aging treatment again. The method has simple and reasonable process, ensures that the finally obtained alloy plate has excellent fracture toughness, and is suitable for industrial application.

Description

Goss + Cube or P + Cube texture aluminum alloy with excellent fracture toughness and preparation method thereof

Technical Field

The invention belongs to the technical field of non-ferrous metal processing, and particularly relates to a Goss + Cube or P + Cube texture aluminum alloy with excellent fracture toughness and a preparation method thereof.

Background

The Al-Cu-Mg series alloy is one of main structural materials in the aviation industry due to medium strength, good toughness and excellent fatigue resistance, and is particularly frequently applied as an aircraft skin and bulkhead material. However, with the rapid development of the aviation field, the requirement on the aircraft is higher and higher, the service environment of the aircraft is worse, and besides the requirement on basic high strength, the fatigue damage resistance and the fracture toughness have higher requirements. At present, the key performance index of the Al-Cu-Mg series alloy sheet is the fatigue crack propagation rate, and a plurality of technical patents for improving the fatigue crack propagation resistance through texture control have been developed. The main key performance index for the Al-Cu-Mg alloy medium plate and thick plate is fracture toughness. It is well known that the service condition of the fracture toughness of the alloy is under the action of uniaxial tensile stress, which is different from the alternating stress service condition of fatigue service. The size of fracture toughness stress is close to the yield strength of the alloy and is far higher than the fatigue low load stress; the fracture crack propagation rate is also much higher than the fatigue crack propagation rate. This means that the damage mechanism of fracture toughness is greatly different from the fatigue damage mechanism. How to improve the fracture toughness of the series alloy medium plate material becomes a problem to be solved urgently, and the method has a far-reaching significance for the application and development of the series alloy in the aerospace field.

Studies have shown that texture is a key factor affecting the fatigue crack propagation rate. It is believed that recrystallization of the Goss 110 <001> and P110 <221> grains is advantageous in improving the fatigue crack propagation resistance of the alloy. The reason is that the strong Goss or P component enables the {111} surface in the alloy crystal grain to be mostly in or close to the direction of the maximum external shear stress, thereby being beneficial to the slippage of dislocation under the action of alternating stress, improving the crack closure effect and relieving the stress concentration; on the other hand, Goss and P crystal grains have large deflection or torsion angles with surrounding crystal grains, which is beneficial to the deflection of cracks under alternating stress, increases the energy consumed by crack propagation, and improves the fatigue crack propagation resistance of the aluminum alloy. On the contrary, the Brass {110} <112} strained crystal grain has a large torsion or deflection angle with the surrounding crystal grains, but most of {111} planes in the crystal grains are in or far from the direction of maximum applied shear stress, so that the dislocation is not favorable for sliding under the action of alternating stress, stress concentration is easy to induce, and the alloy fatigue performance is not favorable for improving. Copper {112} <111> and S {123} <634> grains also do not contribute to the increase of fatigue resistance due to the smaller torsion and deflection angles with the surrounding grains. The resistance of Cube grains to fatigue crack propagation is between that of Goss and Brass grains.

Some related patents have published that the fatigue properties of alloys can be improved by adjusting the strength of Goss or P texture components by adopting a reasonable processing technique. For example, in the Chinese patent CN103526140A, an Al-Cu-Mg alloy cold-rolled sheet is subjected to high-temperature short-time solid solution (505-. In the Chinese patent CN103045976A, after the cold-rolled sheet is firstly subjected to intermediate annealing at the temperature of 300-440 ℃/20-120min and then subjected to solution quenching treatment at the temperature of 475-505 ℃/10-120min, the aged sheet with the Goss texture strength value of 6.52 is obtained after natural aging for at least 100 hours at room temperature, and the fatigue performance of the aged sheet is also excellent. In the Chinese patent CN10358997A, the Goss texture direction strength of the plate obtained by adopting medium and small deformation hot rolling, primary solid solution, large deformation cold rolling, secondary solid solution and natural aging treatment is 3.72, and the fatigue performance is relatively excellent. In the Chinese patent CN108504915A, by controlling the mass ratio of alloy Cu/Mg, the Goss + P texture plate with higher strength is obtained after the alloy ingot is subjected to homogenization, high-temperature rapid hot rolling, recrystallization annealing, solution quenching and natural aging in sequence. In the Chinese patent CN108103373A, a proper amount of Ag is added into Al-Cu-Mg alloy, the alloy hot rolled plate is subjected to recrystallization annealing at 450 ℃/60-240min and then to solution quenching treatment at 510 ℃/20-120min at 480-.

The above technical patents are all corresponding materials and processing techniques developed for alloy sheet materials, and the key performance index of the alloy sheet material is fatigue crack propagation resistance, while the key performance index of the Al-Cu-Mg series alloy medium plate is fracture toughness. As previously mentioned, service environments that fail in a fracture toughness manner differ from fatigue fracture service environments by three points. Firstly, the fatigue crack propagation is under the alternating stress of low load, and the fracture crack propagation is under the condition of uniaxial tensile stress, and the loading force is close to the yield strength of the alloy. Secondly, a crack closure effect is accompanied during fatigue crack propagation, whereas during fracture crack propagation only cracks open and no cracks close. The propagation speed of a fracture crack is much higher than the fatigue crack propagation speed. This therefore also illustrates that the fatigue mechanism is significantly different from the fracture mechanism. In the research of the invention, the sensitivity coefficient of the crack expansion resistance caused by torsion or deflection angle is reduced under the condition of high-speed crack expansion, and the fracture toughness of the alloy can not be effectively improved by simply improving the texture strength.

At present, the conventional view of the grain size on the fracture toughness generally considers that the small grain size is beneficial to the improvement of the fracture toughness of the alloy, but the influence degree of the grain size with specific orientation on the fracture toughness is not reported in the related technology. The alloy plate is subjected to general fine-grain treatment, so that the preparation cost of the plate is greatly increased, and the fracture toughness of the plate cannot be improved in a specific guiding and efficient manner. The patent studies found that among all oriented grains, there are some grains of specific orientation whose size is extremely sensitive and critical to the fracture toughness, while the size of other oriented grains has a negligible effect on the fracture toughness within a certain order of magnitude. In the plate preparation process, if the grain size of the specific orientation can be specifically reduced, the fracture toughness of the alloy can be efficiently improved, and the preparation cost is reduced, and related preparation technologies are urgently developed.

It can be seen that there is a clear difference in the mechanism of inhibition of fatigue and fracture cracking by grain orientation, and the degree of influence of grain size on fracture toughness is related to its orientation. The existing technical patents aiming at improving the fatigue property of the alloy thin plate can not provide technical guidance for improving the fracture toughness of the medium plate. How to develop a corresponding processing and preparation technology by regulating and controlling specific grain orientation and size under the condition of a fracture failure mode environment, the improvement of the fracture toughness of the medium plate is particularly critical and urgent, and the method has important significance for improving the application level of the alloy medium plate in the field of aviation.

Disclosure of Invention

In view of the above, the invention aims to provide a Goss + Cube or P + Cube texture aluminum alloy material with excellent fracture toughness and a preparation method thereof, so as to overcome the defects of the prior art, solve the technical blank of alloy fracture toughness from the aspects of regulating and controlling grain orientation and size, and prepare the Goss + Cube or P + Cube texture aluminum alloy material with fine grains, high strength and high fracture toughness through reasonable component proportion and a corresponding hot working process.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

the Goss + Cube or P + Cube textured aluminum alloy with excellent fracture toughness comprises, by mass, 3.5-4.2% of Cu, 1.0-1.5% of Mg, 0.1-0.28% of Zr, 0.05-0.7% of Mn, 0.02-0.09% of Ti, 0.06% of Fe, 0.06% of Si and the balance of Al; the sum of the mass percentages of the components is 100 percent.

Preferably, in the aluminum alloy matrix, the texture strength of Goss + Cube or P + Cube is more than or equal to 10.33, and the texture strength of Brass + Copper + S is less than or equal to 5.64.

Preferably, the average grain sizes of the three types of Goss, Cube and P in the aluminum alloy matrix are 29.2-53.7 μm respectively.

Preferably, the thickness of the aluminum alloy is 22-70.4 mm.

The invention also provides a method for preparing the Goss + Cube or P + Cube texture aluminum alloy with excellent fracture toughness, which comprises the steps of carrying out long-time solution treatment, water quenching treatment and artificial aging treatment on an aluminum alloy plate containing specific components, then carrying out high-temperature medium-large deformation hot rolling, then carrying out recrystallization annealing treatment, and finally carrying out solution treatment, water quenching and natural aging treatment again.

Preferably, the temperature is 465-488 ℃ and the time is 60-132 hours when the solution treatment is carried out for a long time for the first time; the temperature of the artificial aging is 25-148 ℃, and the time is 24-168 hours.

Preferably, when the hot rolling treatment is carried out at high temperature and medium and large deformation, the rolling temperature is 430-470 ℃, and the rolling deformation is 84-95%.

Preferably, the temperature of the recrystallization annealing treatment is 300-350 ℃, and the time is 120-360 min.

Preferably, the temperature is 470-500 ℃ and the time is 10-40 min during the solution treatment again; the time of natural aging is at least 96 h.

The invention also provides the Goss + Cube or P + Cube texture aluminum alloy with excellent fracture toughness or the aluminum alloy material prepared by the preparation method, which is applied to structural materials such as airplane wallboards, frames, propellers and the like.

The processing method comprises the steps of firstly adopting long-time solution treatment to fully dissolve a second phase into an aluminum alloy matrix, and then precipitating fine and dispersed Al from the matrix through water quenching and aging treatment₃A second phase of Zr, S and theta. Compared with Al-Cu-Mg alloy without Zr addition, Al₃The Zr second phase can effectively activate and promote octahedra (111) in the hot rolling process<110>The slippage of the slippage system is beneficial to the rotation of the random texture to the Brass texture, and a stronger Brass texture is formed. Al can be effectively crushed by adopting high-temperature and large-deformation hot rolling treatment₃The Zr, S and theta second phases are distributed in the alloy matrix more uniformly and dispersedly, and the nucleation and growth of random grains in the subsequent recrystallization process are effectively reduced. Subsequent recrystallization annealing and solid solution process treatment, small size and dispersedly distributed S and thetaThe second phase being in particular Al₃The Zr phase can effectively induce the particle-induced nucleation (PSN) effect, the PSN effect can not inhibit the preferential growth of Goss, P and Cube grains, the nucleation number of three types of oriented grains in deformed grains (mainly Brass grains and containing a small amount of Copper and S grains) can be effectively increased, the deformed texture is effectively consumed, and therefore the strong Goss, P and Cube textures with small grain sizes can be obtained. And in the subsequent quenching and aging processes, the Goss, P and Cube tissue morphology does not change due to the lower temperature. The total number of deflection points is increased as much as possible in the crack propagation process by selectively reducing the grain sizes of Goss, P and Cube and maintaining the strength of the Goss, P and Cube, so that the crack propagation resistance and the crack toughness are effectively improved, and the method is suitable for industrial application.

In the Al-Cu-Mg-Zr alloy matrix, the texture strength of Goss + Cube or P + Cube is more than or equal to 10.33, and the texture strength of Brass + Copper + S is less than or equal to 5.64. The average grain sizes of the three types of Goss, Cube and P are 29.2 to 53.7 μm.

Compared with the prior art, the Goss + Cube or P + Cube texture aluminum alloy with excellent fracture toughness and the preparation method thereof have the following advantages:

the aluminum alloy medium plate has the tensile strength of 435.2-457.3 MPa, the yield strength of 271.6-312.0 MPa, the elongation of 20.3-24.1% and the fracture toughness of 37.5-43.8Mpa m^1/2。

The method has simple and reasonable process, fully dissolves the second phase back into the alloy matrix through the first long-time solution treatment and eliminates the texture, then precipitates the second phase which is uniformly dispersed and distributed through water quenching and aging treatment, and obtains the strong Brass texture and further refines Al through the high-temperature medium-large deformation hot rolling treatment₃The second phase of Zr, S and theta is treated by annealing and solid solution process to make S and theta in the plate, especially Al₃The Zr second phase effectively induces the particle-excited nucleation effect, effectively increases the Goss, P or Cube crystal grain nucleation quantity and consumes the Brass, S and Copper deformation textures. In addition, S, theta and Al₃The Zr second phase has fine size and is distributed in a dispersed way, the preferential growth of Goss, P and Cube oriented grains is not damaged, and G with fine grains and high strength is obtainedoss + Cube or P + Cube texture. In the subsequent quenching and aging processes, the Goss, P and Cube structure forms are not changed due to the lower temperature, so that the finally obtained alloy plate has excellent fracture toughness and is suitable for industrial application.

Drawings

FIG. 1 is a graph showing an orientation distribution function of hot rolling of an alloy of example 1 of the present invention, which was subjected to 488 ℃/132h solution water quenching and 148 ℃/24h aging treatment, and then was subjected to a deformation of 87% at a constant temperature of 440 ℃.

FIG. 2 is a graph showing the orientation distribution function of alloy of comparative example 1 of the present invention, which was subjected to 475 ℃/50h solution water quenching and 35 ℃/158h aging treatment, and then hot rolled at 470 ℃ with a deformation of 94.9%.

As can be seen from fig. 1 and 2, compared to example 1, the hot rolling temperature of comparative example 1 is lower and the deformation amount is small, and theoretically, the temperature with large deformation amount is more favorable for the formation of Brass texture, but the comparison result of ODF graphs shows that the strength of Brass texture obtained by large hot rolling temperature and large deformation amount is smaller, which indicates that the addition of Zr in example 1 is favorable for the formation of Brass texture during hot rolling.

FIG. 3 is an orientation distribution function chart of the alloy of example 8 of the present invention, which is subjected to 488 ℃/132h solution water quenching and 148 ℃/24h aging treatment, then hot rolling with a deformation of 95% at a constant temperature of 470 ℃, annealing at 350 ℃/360min, and then solution and water quenching at 500 ℃/40 min.

FIG. 4 is a graph showing an orientation distribution function of 481 ℃/102h solution quenching and 118 ℃/48h aging treatment, followed by hot rolling at 460 ℃ for 90% deformation, annealing at 340 ℃/270min, followed by 490 ℃/30min solution quenching and water quenching in example 2 of the present invention.

FIG. 5 is a graph showing an orientation distribution function of 475 ℃/50h solution quenching and 35 ℃/158h aging treatment in comparative example 1, hot rolling with a deformation of 87% at a constant temperature of 440 ℃, annealing at 310 ℃/150min, and then 475 ℃/15min solution quenching and water quenching.

FIG. 6 is an orientation distribution function diagram of comparative example 2 of the present invention, which was subjected to 475 ℃/80h solution water quenching and 75 ℃/108h aging treatment, then hot rolling with a deformation of 97% at a constant temperature of 450 ℃, annealing at 380 ℃/150min, and then solution and water quenching at 495 ℃/50 min.

As can be seen from FIGS. 3-6, the texture strengths of the sheets Goss + Cube, P + Cube and Brass + Copper + S obtained in the final aged state of example 8 were 10.75, 8.04 and 5.64, respectively. Example 2 the texture strengths of the final aged Goss + Cube, P + Cube and Brass + Copper + S plates were 9.79, 10.7 and 3.69, respectively. Comparative example 1 the texture strengths of the final aged Goss + Cube, P + Cube and Brass + Copper + S sheets were 3.94, 2.98 and 6.34, respectively. Comparative example 2 the texture strengths of the final aged Goss + Cube, P + Cube and Brass + Copper + S sheets were 10.52, 8.46 and 7.13, respectively. By comparison, the Goss + Cube texture strength value of example 8 is more than 10, the Brass + Copper + S texture strength is 5.64 lower, the P + Cube texture strength of example 2 is more than 10, and the Brass + Copper + S texture strength is 3.69 lower. The Goss + Cube and P + Cube strength values obtained in comparative example 1 are small, while the Goss + P texture strength value obtained in comparative example 2 is greater than 10, but the Brass + Copper + S strength value is as high as 7.13. This indicates that within the scope of the claims, a Goss + Cube or P + Cube texture with high strength can be obtained at the same time, and that the Brass + Copper + S texture has low strength.

FIG. 7 is an EBSD map of the alloy of example 8 of the present invention, which is subjected to 488 ℃/132h solution water quenching and 148 ℃/24h aging treatment, then hot rolling with a deformation of 95% at a constant temperature of 470 ℃, annealing at 350 ℃/360min, and then solution and water quenching at 500 ℃/40 min.

FIG. 8 is an EBSD map of comparative example 1 of the present invention, which is subjected to 475 ℃/50h solution water quenching and 35 ℃/158h aging treatment, then hot rolling with a deformation of 94.9% at a constant temperature of 440 ℃, annealing at 310 ℃/150min, and then solution and water quenching treatment at 475 ℃/15 min.

As can be seen from a comparison of FIGS. 7 and 8, the average size of Goss, P and Cube grains obtained in example 8 was 45.8. mu.m. The average size of Goss, P and Cube grains obtained by the process of comparative example 1 was 108.5 μm.

Detailed Description

Unless defined otherwise, technical terms used in the following examples have the same meanings as commonly understood by one of ordinary skill in the art to which the present invention belongs. The test reagents used in the following examples, unless otherwise specified, are all conventional biochemical reagents; the experimental methods are conventional methods unless otherwise specified.

The present invention will be described in detail with reference to examples.

Example 1

The alloy comprises (by mass percentage, the sum of the mass percentages of the components is 100%) Cu 4.0%, Mg 1.5%, Zr 0.28%, Mn 0.7%, Ti 0.09%, Fe 0.05%, Si 0.05% and the balance Al, and is prepared by hot rolling at 488 ℃/132h in water quenching and aging at 148 ℃/24h, hot rolling at 440 ℃ at a constant temperature of 87% in deformation (thickness of 57.2mm), annealing at 350 ℃/360min, solution-quenching at 500 ℃/40min in water quenching, and standing at room temperature for at least 96 h. The texture strength of the obtained plate Goss + Cube is 9.01, the texture strength of the plate P + Cube is 11.76, the texture strength of the plate Brass + Copper + S is 3.65, and the average grain size of the plate Goss + P + Cube is 40.6 microns. The tensile property is as follows: the tensile strength is 450.6MPa, the yield strength is 305.4MPa, the elongation is 23.1 percent, and the fracture toughness is K_IQ＝42.7Mpa*m^1/2。

Example 2

The alloy comprises (by mass percentage, the sum of the mass percentages of the components is 100%) Cu 4.2%, Mg 1.4%, Zr 0.21%, Mn 0.5%, Ti 0.07%, Fe 0.05%, Si 0.04%, and the balance Al, and is prepared by hot rolling at 440mm thickness, performing 481 ℃/102h solution water quenching and 118 ℃/48h aging treatment, performing hot rolling at 460 ℃ at a constant temperature with a deformation of 90% (the thickness is 44mm), performing 340 ℃/270min annealing, performing 490 ℃/30min solution and water quenching treatment, and standing at room temperature for at least 96 h. The texture strength of the obtained plate Goss + Cube is 9.79, the texture strength of the plate P + Cube is 10.7, the texture strength of the plate Brass + Copper + S is 3.69, and the average grain size of the plate Goss + P + Cube is 49.1 mu m. The tensile properties of the resulting sheet were: the tensile strength is 452.9MPa, the yield strength is 312.0MPa, the elongation is 23.4 percent, and the fracture toughness is K_IQ＝41.8Mpa*m^1/2。

Example 3

The alloy comprises (by mass percentage, the sum of the mass percentages of the components is 100%) Cu 4.0%, Mg 1.5%, Zr 0.15%, Mn 0.6%, Ti 0.08%, Fe 0.04%, Si 0.03%, and the balance Al, and is prepared by hot rolling a 400mm thick hot rolled plate, performing 475 ℃/98h solution water quenching and 108 ℃/55h aging treatment, performing 92% deformation hot rolling (the thickness is 35.2mm) at 465 ℃ constant temperature, performing 345 ℃/240min annealing, performing 485 ℃/40min solution water quenching treatment, and finally standing at room temperature for at least 96 h. The texture strength of the obtained plate Goss + Cube is 11.6, the texture strength of the plate P + Cube is 8.49, the texture strength of the plate Brass + Copper + S is 2.94, and the average grain size of the plate Goss + P + Cube is 53.7 microns. The tensile properties of the resulting sheet were: the tensile strength is 457.3MPa, the yield strength is 310.4MPa, the elongation is 22.8 percent, and the fracture toughness is K_IQ＝39.9Mpa*m^1/2。

Example 4

The alloy comprises (by mass percentage, the sum of the mass percentages of the components is 100%) Cu 3.8%, Mg 1.3%, Zr 0.17%, Mn 0.5%, Ti 0.05%, Fe 0.04%, Si 0.04%, and the balance Al, and is prepared by subjecting a hot-rolled plate with a thickness of 400mm to 473 ℃/92h solution water quenching and 75 ℃/95h aging treatment, hot-rolling with a deformation of 88% (with a thickness of 52.8mm) at a constant temperature of 455 ℃, annealing at 320 ℃/220min, carrying out 478 ℃/20min solution water quenching treatment, and finally standing at room temperature for at least 96 h. The texture strength of the obtained plate Goss + Cube is 9.44, the texture strength of the plate P + Cube is 10.33, the texture strength of the plate Brass + Copper + S is 5.80, and the average grain size of the plate Goss + P + Cube is 35.9 mu m. The tensile properties of the resulting sheet were: the tensile strength is 439.5MPa, the yield strength is 285.7MPa, the elongation is 24.1 percent, and the fracture toughness is K_IQ＝43.8Mpa*m^1/2。

Example 5

The alloy comprises (by mass) Cu 3.6%, Mg 1.0%, Zr 0.12%, Mn 0.1%, Ti 0.04%, Fe 0.04%, Si 0.03%, and Al in balance, and is prepared by subjecting a hot-rolled plate of 400mm thickness to 469 deg.C/70 h solution quenching and 45 deg.C/128 h quenchingPerforming effect treatment, performing hot rolling (with the thickness of 61.6mm) with the deformation of 86% at the constant temperature of 439 ℃, annealing at the temperature of 310 ℃/150min, performing solid solution and water quenching at the temperature of 475 ℃/15min, and finally standing at room temperature for at least 96 h. The texture strength of the obtained plate Goss + Cube is 11.24, the texture strength of the plate P + Cube is 9.25, the texture strength of the plate Brass + Copper + S is 3.41, and the average grain size of the plate Goss + P + Cube is 29.2 microns. The tensile properties of the resulting sheet were: the tensile strength is 440.3MPa, the yield strength is 281.3MPa, the elongation is 20.3 percent, and the fracture toughness is K_IQ＝37.5Mpa*m^1/2。

Example 6

The alloy comprises the following components (mass fraction, the sum of the mass fractions of the components is 100%) of Cu 3.5%, Mg 1.15%, Zr 0.14%, Mn 0.08%, Ti 0.05%, Fe 0.05%, Si 0.05% and the balance of Al, and is a hot rolled plate with the thickness of 400mm, the hot rolled plate is subjected to 466 ℃/80h solid solution water quenching and 57 ℃/120h aging treatment, then the hot rolled plate is subjected to hot rolling (with the thickness of 48.4mm) with the deformation of 89% at the constant temperature of 449 ℃, then the annealing is carried out at 325 ℃/170min, then the hot rolled plate is subjected to 479 ℃/25min and water quenching treatment, and finally the hot rolled plate is placed at room temperature for at least 96 h. The texture strength of the obtained plate Goss + Cube is 9.86, the texture strength of the plate P + Cube is 12.75, the texture strength of the plate Brass + Copper + S is 4.09, and the average grain size of the plate Goss + P + Cube is 50.7 microns. The tensile properties of the resulting sheet were: the tensile strength is 448.7MPa, the yield strength is 293.7MPa, the elongation is 20.9 percent, and the fracture toughness is K_IQ＝37.9Mpa*m^1/2。

Example 7

The alloy comprises the following components (mass percentage, the sum of the mass percentages of the components is 100%) of Cu 3.55%, Mg 1.2%, Zr 0.1%, Mn 0.05%, Ti 0.02%, Fe 0.03%, Si 0.05% and the balance of Al, and is a hot rolled plate with the thickness of 400mm, the hot rolled plate is subjected to solid solution water quenching at 465 ℃/60h and aging treatment at 25 ℃/168h, then hot rolled with the deformation of 84% at the constant temperature of 430 ℃ (the thickness is 70.4mm), then annealed at 300 ℃/120min, then subjected to solid solution treatment at 470 ℃/10min and water quenching treatment, and finally placed at room temperature for at least 96 h. The texture strength of the obtained plate Goss + Cube is 11.22, the texture strength of the plate P + Cube is 8.43, the texture strength of the plate Brass + Copper + S is 3.90, and the average crystal grains of the plate Goss + P + CubeThe size was 39.2. mu.m. The tensile properties of the resulting sheet were: the tensile strength is 435.2MPa, the yield strength is 271.6MPa, the elongation is 22.8 percent, and the fracture toughness is K_IQ＝38.6Mpa*m^1/2。

Example 8

The alloy is prepared by the steps of 488 ℃/132h solution water quenching and 148 ℃/24h aging treatment of 440mm hot rolled plate alloy, then hot rolling with the deformation of 95 percent (the thickness is 22mm) at the constant temperature of 470 ℃, then annealing at 350 ℃/360min, then solution and water quenching treatment at 500 ℃/40min, and finally standing at room temperature for at least 96 h. The texture strength of the obtained plate Goss + Cube is 10.75, the texture strength of the plate P + Cube is 8.04, the texture strength of the plate Brass + Copper + S is 5.64, and the average grain size of the plate Goss + P + Cube is 45.8 microns. The tensile properties of the resulting sheet were: the tensile strength is 443.2MPa, the yield strength is 289.5MPa, the elongation is 21.5 percent, and the fracture toughness is K_IQ＝40.6Mpa*m^1/2。

Comparative example 1

The alloy comprises (by mass percentage, the sum of the mass percentages of the components is 100%) Cu 3.7%, Mg 1.2%, Mn 0.02%, Ti 0.05%, Fe 0.04%, Si 0.05% and the balance Al, and is prepared by subjecting a 440mm thick hot-rolled plate to 475 ℃/50h solution water quenching and 35 ℃/158h aging treatment, hot rolling at 440 ℃ at a constant temperature with a deformation of 94.9% (thickness is 22.4mm), annealing at 310 ℃/150min, subjecting to 475 ℃/15min solution water quenching treatment, and standing at room temperature for at least 96 h. The texture strength of the obtained plate Goss + Cube is 3.94, the texture strength of the plate P + Cube is 2.98, the texture strength of the plate Brass + Copper + S is 6.34, and the average grain size of the plate Goss + P + Cube is 108.5 microns. The tensile properties of the resulting sheet were: the tensile strength is 461.7MPa, the yield strength is 281.9MPa, the elongation is 18.7 percent, and the fracture toughness is K_IQ＝32.4Mpa*m^1/2。

Comparative example 2

The alloy comprises (by mass) Cu 3.9%, Mg 1.0%, Zr 0.7%, Mn 0.07%, Ti 0.04%, Fe 0.05%, Si 0.04%, and Al in balance, and is prepared by subjecting a hot-rolled plate of 400mm thickness to 475 deg.C/80 hr solution quenching and refiningAging at 75 ℃/108h, hot rolling (thickness of 13.2mm) with deformation of 97% at constant temperature of 450 ℃, annealing at 380 ℃/150min, solid solution at 495 ℃/50min, water quenching, and standing at room temperature for at least 96 h. The texture strength of the obtained plate Goss + Cube is 10.52, the texture strength of the plate P + Cube is 8.46, the texture strength of the plate Brass + Copper + S is 7.13, and the average grain size of the plate Goss + P + Cube is 78.3 microns. The tensile properties of the resulting sheet were: the tensile strength is 470.6MPa, the yield strength is 309.4MPa, the elongation is 17.5 percent, and the fracture toughness is K_IQ＝35.9Mpa*m^1/2。

Comparative example 3

The alloy composition is the same as that of comparative example 1, the hot rolled plate alloy with the thickness of 400mm is subjected to 475 ℃/50h solution water quenching and 35 ℃/158h aging treatment, then hot rolling with the deformation of 87 percent (the thickness is 57.2mm) is carried out at the constant temperature of 440 ℃, then annealing is carried out at 310 ℃/150min, and then 475 ℃/15min solution water quenching is carried out. Finally standing at room temperature for at least 96 h. The texture strength of the obtained plate Goss + Cube is 3.81, the texture strength of the plate P + Cube is 2.63, the texture strength of the plate Brass + Copper + S is 6.84, and the average grain size of the plate Goss + P + Cube is 95.4 microns. The tensile properties of the resulting sheet were: the tensile strength is 459.8MPa, the yield strength is 284.1MPa, the elongation is 18.6 percent, and the fracture toughness is K_IQ＝33.7Mpa*m^1/2。

TABLE 1 texture Strength values and average grain sizes for examples 1-8 and comparative examples 1-3

Table 2 tensile properties and fracture toughness for examples 1-8 and comparative examples 1-3.

As can be seen from Table 1, examples 1-8 all have Goss + Cube or P + Cube texture with intensity values greater than 10.33, and Brass + Copper + S has lower intensity values within the range of 2.94 to 5.64, and Goss, P and Cube grain sizes are smaller between 29.2 μm and 53.7 μm. The Goss + Cube/P + Cube obtained by the comparative example has a lower strength value, and the grain sizes of Goss, P and Cube obtained by the comparative example are larger and are between 78.3 and 108.5 mu m.

It can be seen from the attached Table 2 that the tensile strength values of examples 1 to 8 are slightly smaller than those of comparative examples 1 to 3, and the yield strengths are not so different, but the fracture toughness values of examples 1 to 8 are 37.5 to 43.8MPa m^1/2The fracture toughness values of comparative examples 1-3 are smaller than 32.4-35.9Mpa^1/2In the meantime.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. A preparation method of Goss + Cube or P + Cube texture aluminum alloy with excellent fracture toughness is characterized in that: the aluminum alloy comprises, by mass, 3.5-4.2% of Cu, 1.0-1.5% of Mg, 0.1-0.28% of Zr, 0.05-0.7% of Mn, 0.02-0.09% of Ti, 0.06% of Fe, 0.06% of Si and the balance of Al; the sum of the mass percentages of the components is 100 percent;

the preparation method comprises the following steps of carrying out first long-time solid solution, water quenching and artificial aging treatment on an aluminum alloy plate containing specific components, then carrying out high-temperature medium and large deformation hot rolling, then carrying out recrystallization annealing treatment, and finally carrying out solid solution, water quenching and natural aging treatment again;

the temperature is 465-488 ℃ and the time is 60-132 h when the solution treatment is carried out for a long time for the first time; the temperature of the artificial aging is 25-148 ℃, and the time is 24-168 hours;

when hot rolling treatment is carried out at high temperature and medium and large deformation, the rolling temperature is 430-470 ℃, and the rolling deformation is 84-95%;

during the recrystallization annealing treatment, the temperature is 300-350 ℃, and the time is 120-360 min;

performing solid solution treatment again at 470-500 ℃ for 10-40 min; the time of natural aging is at least 96 h;

in the aluminum alloy matrix, the texture strength of Goss + Cube or P + Cube is more than or equal to 10.33, and the texture strength of Brass + Copper + S is less than or equal to 5.64; in the aluminum alloy matrix, the average grain sizes of the three types of Goss, Cube and P are 29.2-53.7 μm respectively.

2. The method for preparing Goss + Cube or P + Cube texture aluminum alloy with excellent fracture toughness as claimed in claim 1, wherein: the thickness of the aluminum alloy plate is 22-70.4 mm.

3. The method for preparing Goss + Cube or P + Cube texture aluminum alloy with excellent fracture toughness as claimed in claim 1, wherein: the first long-time solution treatment time is 80-132 h; the temperature of artificial aging is 75-148 ℃, and the time is 55-120 h.

4. The method for preparing Goss + Cube or P + Cube texture aluminum alloy with excellent fracture toughness as claimed in claim 1, wherein: the time for recrystallization annealing treatment is 170-360 min.

5. The aluminum alloy material prepared by the preparation method of the Goss + Cube or P + Cube texture aluminum alloy with excellent fracture toughness according to any one of claims 1 to 4 is applied to structural materials of airplane wall plates, frames or propellers.