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CN-121992320-A - Method and system for regulating and controlling residual stress of high-strength aluminum alloy thin-wall ribbed component

CN121992320ACN 121992320 ACN121992320 ACN 121992320ACN-121992320-A

Abstract

The invention discloses a method and a system for regulating and controlling residual stress of a high-strength aluminum alloy thin-wall ribbed component. The invention relates to the field of material processing, and aims to solve the problems that in the prior art, macro-micro coupling residual stress of a high-strength aluminum alloy thin-wall ribbed component is difficult to systematically and cooperatively regulate and control, and processing deformation, size deviation and stress corrosion cracking are easy to cause. The method comprises the steps of applying a tensile preload to a component to generate 0.2-0.8% global inelastic strain, unloading after load retention, applying high-frequency ultrasonic vibration to the surface of the component, enabling the amplitude of local alternating stress to be not lower than 10% of the local residual stress value of a corresponding area, performing programmed cryogenic heat cycle treatment, enabling the lowest temperature to be less than or equal to 150 ℃, and controlling the temperature rising and falling rate to be between 0.5 ℃ and 5 ℃ per minute. After the treatment of the invention, the residual stress peak value of the component is obviously reduced, the dimensional stability is greatly improved, the microstructure is optimized, and the service performance is enhanced.

Inventors

  • HUANG YUANCHUN
  • LIU YU

Assignees

  • 中南大学

Dates

Publication Date
20260508
Application Date
20260406

Claims (10)

  1. 1. The method for regulating and controlling the residual stress of the high-strength aluminum alloy thin-wall ribbed member is characterized by comprising the following steps of: Step one, applying a tensile preload to a component, enabling the component to generate global inelastic strain of 0.2-0.8%, enabling the maximum equivalent stress of the cross section of the component to be lower than 85% of the yield strength of the material at the temperature, and unloading after load retention according to preset load retention time; Step two, applying high-frequency ultrasonic vibration to the surface of the component treated in the step one, wherein the amplitude of local alternating stress generated by the high-frequency ultrasonic vibration is not less than 10% of the value of local residual stress of the corresponding area of the component; and thirdly, performing programmed cryogenic cyclic treatment on the component treated in the second step, wherein the lowest temperature of the cryogenic cyclic treatment is less than or equal to-150 ℃, and the temperature rising and falling rate is controlled between 0.5 ℃ per minute and 5 ℃ per minute.
  2. 2. The method for regulating and controlling residual stress of a high-strength aluminum alloy thin-wall ribbed member according to claim 1, wherein in the first step, the preset holding time t_hold and the maximum section thickness d of the member satisfy the following relationship that t_hold is equal to or greater than 2d, wherein the unit of t_hold is minutes, and the unit of d is millimeters.
  3. 3. The method for regulating and controlling residual stress of a high-strength aluminum alloy thin-wall ribbed member according to claim 1, wherein in the first step, the unloading process adopts slow linear unloading, and the unloading speed is not more than 0.5 mm/min.
  4. 4. The method for regulating and controlling residual stress of a high-strength aluminum alloy thin-wall ribbed member according to claim 1, wherein in the second step, when the high-frequency ultrasonic vibration is applied, a mechanical arm is used for carrying a focusing ultrasonic transducer to scan the surface of the member.
  5. 5. The method for adjusting and controlling residual stress of a high-strength aluminum alloy thin-wall ribbed member according to claim 4, wherein in the second step, the scanning is performed in a double-frequency alternating mode.
  6. 6. The method for adjusting and controlling residual stress of a high-strength aluminum alloy thin-wall ribbed member according to claim 5, wherein in the second step, the dual-frequency alternating pattern comprises 20kHz and 40kHz.
  7. 7. The method for adjusting and controlling residual stress of a high-strength aluminum alloy thin-wall ribbed member according to claim 4, wherein in the second step, the scanned path overlap ratio is not lower than 30%.
  8. 8. The method for controlling residual stress of a high-strength aluminum alloy thin-wall ribbed member according to claim 4, wherein in the third step, the cycle period of the cryogenic heat cycle treatment is not less than 2.
  9. 9. The method for controlling residual stress of a high-strength aluminum alloy thin-wall ribbed member according to claim 4, wherein in the third step, a static pressure of 0.5 bar-2 bar is applied to the treatment medium in the low-temperature heat preservation stage of the cryogenic heat cycle treatment.
  10. 10. The utility model provides a high strength aluminum alloy thin wall takes muscle component residual stress regulation and control system which characterized in that includes: The macro stress coordination unit is used for applying a tensile preload to the component, so that the component generates 0.2-0.8% of global inelastic strain, the maximum equivalent stress of the cross section of the component is lower than 85% of the yield strength of the material at the temperature, and the material is loaded and unloaded according to the preset loading time; The ultrasonic dislocation engineering unit is used for applying high-frequency ultrasonic vibration to the surface of the component treated by the macro-stress coordination unit, and the amplitude of local alternating stress generated by the high-frequency ultrasonic vibration is not less than 10% of the local residual stress value of the corresponding area of the component; The cryogenic power coupling unit is used for carrying out programmed cryogenic heat cycle treatment on the component treated by the ultrasonic dislocation engineering unit, wherein the lowest temperature of the cryogenic heat cycle treatment is less than or equal to-150 ℃, and the temperature rise and fall rate is controlled between 0.5 ℃ and 5 ℃ per minute; the central intelligent control system is in communication connection with the macro stress coordination unit, the ultrasonic dislocation engineering unit and the cryogenic heat coupling unit and is used for integrally controlling the units to work cooperatively in sequence, and the central intelligent control system comprises an online stress monitoring module and a process parameter dynamic optimization module.

Description

Method and system for regulating and controlling residual stress of high-strength aluminum alloy thin-wall ribbed component Technical Field The invention relates to the technical field of material processing, in particular to a method and a system for regulating and controlling residual stress of a high-strength aluminum alloy thin-wall ribbed component. Background The high-strength aluminum alloy thin-wall ribbed member is widely applied to main bearing structures in the fields of aviation, aerospace and the like by virtue of the characteristics of high specific strength and high rigidity. Such components typically undergo critical processes of high temperature solution and quench hardening during fabrication, however, complex three-dimensional macroscopic residual stress fields are created within the component due to non-uniform cross-sectional cooling and geometric constraints of the "skeleton-skin" structure. Meanwhile, crystal defects such as high-density dislocation, vacancies and the like can be introduced in the quenching process, so that a lattice distortion stress field with microscopic dimensions is formed. In the prior art, a single post-treatment method is often used for treating the residual stress of such components. For example, the method is effective only for simple-section components, is difficult to realize comprehensive and effective stress regulation and control for complex thin-wall ribbed components, has relatively simple and convenient vibration aging operation, has shallow and unstable action effect, cannot go deep into the components to solve the problem of residual stress, and has limited capability of reducing macroscopic residual stress due to the fact that the deep cooling treatment is mainly performed on microscopic defects. The traditional single treatment methods can not systematically and synergistically solve the problem of macro-micro coupling residual stress in the high-strength aluminum alloy thin-wall ribbed component. This results in unpredictable "let-off" distortion of the component during subsequent precision machining, resulting in dimensional errors that severely impact the machining accuracy of the component. More seriously, the existence of residual stress can also cause stress corrosion cracking risk, and the service safety and reliability of the component are greatly reduced. Therefore, it is necessary to provide a method for regulating and controlling the residual stress of the high-strength aluminum alloy thin-wall ribbed member so as to solve the problems. Disclosure of Invention The invention aims to provide a method and a system for regulating and controlling residual stress of a high-strength aluminum alloy thin-wall ribbed component, which are used for solving the problems that the prior art cannot systematically and cooperatively cope with macro-micro coupling residual stress of the high-strength aluminum alloy thin-wall ribbed component, so that subsequent processing deformation, dimension out-of-tolerance and stress corrosion cracking risk are caused. In a first aspect, the invention provides a method for regulating and controlling residual stress of a high-strength aluminum alloy thin-wall ribbed member, which comprises the following steps: And step one, applying a tensile preload to the component, enabling the component to generate global inelastic strain of 0.2-0.8%, enabling the maximum equivalent stress of the cross section of the component to be lower than 85% of the yield strength of the material at the temperature, and unloading after the load is preserved according to the preset load-preserving time. And step two, applying high-frequency ultrasonic vibration to the surface of the component treated in the step one, wherein the amplitude of local alternating stress generated by the high-frequency ultrasonic vibration is not lower than 10% of the value of local residual stress of the corresponding area of the component. And thirdly, performing programmed cryogenic cyclic treatment on the component treated in the second step, wherein the lowest temperature of the cryogenic cyclic treatment is less than or equal to-150 ℃, and the temperature rising and falling rate is controlled between 0.5 ℃ per minute and 5 ℃ per minute. Further, in the first step, the preset holding time t_hold and the maximum section thickness d of the member satisfy the following relation that t_hold is more than or equal to 2d, wherein the unit of t_hold is minutes, and the unit of d is millimeters. Further, in the first step, the unloading process adopts slow linear unloading, and the unloading speed is not more than 0.5mm/min. In the second step, when the high-frequency ultrasonic vibration is applied, the mechanical arm is used for carrying the focusing ultrasonic transducer to scan the surface of the component. Further, in the second step, the scanning adopts a dual-frequency alternating mode. Further, in the second step, the dual-frequency alternating mode includes 2