Study On Car4032Aluminum Alloy Pistons Isothermal Extrusion Process And Numerical Simulation

The piston is an important part of the engine，which work under alternate loadand alternate high-temperature and high-pressure environment, so the property of thepiston has a very important impact on the property of the engine.The making processof piston which used in car is studied in this paper,The property of the casting piston can’t satisfy the require of the car, so adaptextrusion way to make it. But because the thickness of the piston-skirt is thin and theplastic property of4032alloy is not good so that it is very difficult to make the pistonperfectly.On the basis of the experiment data of thermal simulation, The influence ofdeformation temperature and strain rate on flow behavior of the4032aluminium alloywas investigated. The constitutive equation was established and the hot deformationactivation energy was calculated as340914.1J/mol Through processing map beingestablished and deformation microstructure being observed, three unsafe processingzone and the optimum domain occurred at460⁴90°C and0.01⁰.05s^-1with theefficiency of power dissipation of0.3640for hot working was obtained.According to the design feature of the piston, the combined extrusion is used Theresult of numberical simulation show that Thin-walled shaped first and the metal flowstoo fast, easy to produce cracks and other defects, After analysis, two step extrusionmethod is adopted The simulation results show that the two step extrusion method isbetter, the piston metal flows uniformly, we can get the perfectly piston extrusion.