Numerical Simulation And Research Of Aluminum Extrusion

Aluminum alloy products, a saving metal with high efficiency to produce aluminum product by extrusion method, are more and more widely used in our daily life and production areas. In aluminum extrusion industry of China, the extrusion dies designed are generally at the stage of experience. Low success rate resulting in rising overall cost, which have seriously hampered the development of Chinese aluminum extrusion industry. With CAD/CAM/CAE technology in the practical application scope is more and more extensive, how to integrate the numerical simulation technology into the aluminum extrusion process is of a great significance to the effectiveness and development of the entire extrusion industry on the basis of calculation precision and accuracy.This paper first introduces the plane porthole die mold design principles, discusses the arbitrary lagrangian-eulerian methods’basic principles and equations as well as analyzes the numerical modeling of aluminum extrusion process. A production example was simulated and verified the accuracy of the simulation software. Then an extrusion simulation trial was established to exploring the extrusion speed, metal preheat temperature, friction coefficient change to the extrusion process. With the increase of the extrusion speed, billet temperature and die temperature was gradually increased. The highest temperature was located in bearing export while the flow dead zone located in diversion hole of die and the stress of bearing have sharp risen. As different billet preheat temperature was simulated, the deformation metal temperature was gradually increased along the extrusion direction while the increase of billet preheat temperature, and extrusion pressure was declined gradually. For the increase of the friction coefficient, the overall temperature was risen. Apart from that, it also discusses the impacts of flat die angle changes to die stress, metal flow uniformity as well as metal pressure. Different porthole die’s split ratio effect to the extrusion die temperature and die stress distribution is contained in this paper too.Basing on discuss of extrusion technology and die structure to the extrusion process, at the end of this paper, we choose a kind of aluminum radiator to experiment. Design the extrusion die, profiles were assembled after tryout, but level degrees were below the standard. In order to find the specific reasons, numerical simulation was carried out to the initial design; finite element analysis model was established too. Also, steady state and transient flow of the extrusion process were simulated to study how the process parameters effect the extrusion condition, profile exports displacement, the metal flow velocity, temperature distribution, metal flow stress, transient pressure changes and die temperature, die stress were analyzed. By analyzing, increase promote flow angle in up die, add baffles on the lower die and modify bearing length programs were proposed, then modification die and virtual simulation second time, the result shows effectively solve the initial die design problem which is non-uniform velocity distribution, final revamp the die and put into production. The final profiles produced were qualified and can be assembled to use. Simulation results good coincide with the production, by numerical simulation method, we can guide the die design and modified, instead of the tryout and rework process like before.