| This thesis focuses on the production of 6082 extruded complex hollow profiles. The aim is to explore how the numerical simulation coupled with physical simulation would guide the manufacture of 6082 hollow profiles. With the help of Gleeble1500D, flow behaviors of as cast 6082 Al alloy at high temperature were studied to build the hyperbolic sine function describing its features about the flow stress. The results from the physical simulation reflecting the deformation features at high temperature could be imported into the numerical simulation tool HyperXtrude8.0 to define the would-be used materials and their deformation characteristics. The extrusion processing parameters are in line with the values used in the previous numerical model. By measuring the engineering outputs like pressure and temperature, feedback could be accumulated to optimize the boundaries in the numerical models. Mechanical and Micro structural tests have been conducted to analyze the properties of the extruded hollow profiles at typical areas.Some conclusions could be arrived at after the implementations of hot compressions, numerical simulations, extrusions, testing of engineering parameters and analysis of the properties of extruded profiles.①As cast 6082 alloy is a positive strain rate sensitive material. The flow stress model of the as cast 6082 Al alloy could be interpreted by using hyperbolic sine function. According to the definition of the hyperbolic sine function, flow stressσcould be written as the function of the Zener-Hollomon parameter. Seen in the following:σ= 40 ln {(Z/ 2.84×109)1/5.97+ [(Z/2.84×109)2/5.97+1]1/2} By taking advantage of SEM-ECC, the grain size in the compressed sampled could be seen. The grain size increases with the increasing of the temperature and decreasing of the stain rate.②The 3D model of the porthole die was built in the working environment of UG4.0 and then imported to the HyperXtrude8.0 for simulation. The results from the numerical simulation by using HyperXtrude8.0 well reflect the trend of temperature and pressure in the following extrusions. The speed gradients in the numerical models are mostly in accordance with the speeds outside the bearing of the porthole die.③The flow stress model of 6082 Al alloy coupled with the 3D numerical simulation could provide guidance to realize the production of the complex hollow profiles. Concerning with the complex porthole die used in the experiments, 480℃could be chosen as the extrusion temperature to obtain sound profiles.④The hollow profiles got from extrusion are of good surface quality and without severe distortions. After a series of heat treatment, the mean HV value is 110.0 and the mean tensile strength is 296.38MPa which could meet the engineering requirements. Thicker places from the cross section are likely to be of better mechanical properties.⑤SEM-ECC could be used as a powerful tool to observe the micro structural information of the deformed 6082 Al alloy. The sampling process for ECC is very easy to command, so it has to potential to be promoted in the micro structural analysis of the deformed 6082 specimen.
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