Investigation Of Mechanism And Application On The Collaborative Of Shape And Property In Creep Age Forming Of The High-strength Aluminum Alloy

The creep age forming technology of aluminum alloy, which utilize the coexistence of the creep forming and the age strengthening ingeniously, has been adopted as a collaborative manufacturing method of forming and material. Even so, the development of this technology is faced with the accurate prediction of the theoretical model and the high-performance manufacturing of the components. This paper starts from the systematic basic experiments, which is about the influences of the thermo-mechanical coupling on the shape and property of the components, the relations of the stress relaxation, the precipitating of the nano strengthening phase and the material properties have been ascertained. On the basis of the results, the typical models for characterization and prediction have been established. And then, targeted researches were conducted aiming to the reducing material properties, which has appeared in the creep formed samples. Based on the results, the mechanisms of the orientation effect and the control method has been ascertained, and the corresponding control theory and methods were developed preliminary. At last, the effect of the control methods were proved by the creep age forming tests based on the forming tools, the built prediction methods of the shape and the material property were applied in the trial-manufacture process of the aircraft protection door. There are a total of99figures,5tables and137references in this paper. By the experiment study of the creep aging forming of2124and7475aluminum alloys, the main research results and innovations are as below:(1) The evolution rules and the quantitative relation of the creep behavior, the mechanical behavior and the microstructure in the creep aging process of aluminum alloys have been obtained.(2) The constitutive models for temperature-related creep aging processes of2xxx and7xxx aluminum alloys have been established.(3) The generation mechanisms of the orientation effect, which causes the degraded material property of2124aluminum alloy, have been revealed.(4) The macro/micro characteristics of the optimized2124aluminum alloy samples during creep age forming with single/double curvature have been investigated. And the control technique of this alloy in different forming processes is formed(5) The manufacturing approaches of the ribbed protection door in ARJ21aircraft have been built starting from the7475aluminum alloy ingot casting to creep forming in vacuum autoclave. The favorable results provide a reliable design method and process route for the creep manufacturing of this kind of parts.