Simulation And Experiment Research Of Tension Straightening For Large Size Aluminum Alloy Plate

Tension straightening process is an effective method for eliminating strip shape problems of large size aluminum alloy plate used in aerospace. However, due to limitation of objective factors such as production cost, field testing research is not convenient to be done and technological parameter are often obtained by experience summarization. Based on heat transfer theory, materials science and mechanics, combining with practical manufacture, change laws of plate’s shape during non-uniform quenching and tension straightening process were studied and setting of technological parameter in industrial production was probed by the way of the combination of finite element simulation calculation and simulation experiment.Firstly, research background and status at home and abroad of this topic were introduced, and the research methods and contents were discussed in this paper. Then plate shape’s classification, presentation and detection methods of large size aluminum alloy plate were summarized and compared. The effects and optimizing rule of aluminum alloy plate’s phase change caused by quenching were discussed and the harm from quenching residual stress was analyzed. Based on the theory of elastic-plastic mechanisms, the change of plate shape of thin-walled plate and thick one were deduced theoretically, and then differences and applied range were obtained.Secondly, researched on flatness, quenching-tension straighting process of large size aluminum alloy plate was studied by using MSC.MARC. The warping deformation of plate during quenching mainly reflects in the length direction. The warping is severer with the increase of heat transfer intensity ratio, and under the same non-uniform transfer ratios, with increase of thickness, warping become larger. Tension can improve plate quality, the main effect of pretension on warping focuses on the early stage of plastic deformation. With the increase of stretching quantity, straightening effects are better, but the risks of plate crack and clamp slip increase.Lastly, the source of error was analyzed by comparing the simulation calculation model with simulation experiment by analyzing yield strength and shape changes of plate during heating process. The conclusion that yield strength would decrease and softening phenomena would come into being and plate deformation create along sustaining direction with the increase of temperature was obtained.