Numerical Simulation Of Flow Field And Temperature Field Of Aluminium Alloy Piston In Metal Gravity Casting Process

The piston is one of working strength biggest components in the engine. It should have the ability of suffering higher thermal and mechanical load, Request special technique of manufacture and extremely high precision. But the piston structure is complex, wall unevenness, has a certainty difficulty in the process of production.In this paper, a certain factory ZL108 piston is regarded as the research object. Through analysis structure of piston, gating systems process is primary designed, and position, form and dimension of the insulating riser are determined, then work out foundry technique plan. We used the three dimensional software UG, to establish solid modeling of the piston. Then through casting process numerical simulation software ProCAST to import, grid division and simulation parameters of setting for the modeling, carries on the numerical simulation.Has carried on the simulation using the ProCAST software to piston details' different foundry technique plan. Firstly, has simulated the traditional foundry technique plan. The analysis indicated: this craft can achieve sufficient steady purpose in the filling process, but the casting each place temperature difference is big, the thick main point turn into heat concentration region. And the coagulation basically is the top-down sequence coagulation way, combination of piston and riser is more heat reservoir, easy to form the hot festival. Moreover the casting head is quite unwieldy, waste massive molten metals, the product rate is low. Secondly, has simulated different insulating riser shapes in the present foundry technique plan. The result indicated: under two kind of shape rising head functions, the casting conforms to the coagulation order from bottom to top, plays well makes up shrinks the effect. Because on the small under big rising head shape and the casting contact spot are big, therefore the heat-affected zone is also big, may enhance the molten metal the use factor, and enhances makes up shrink ability. Finally, has simulated under three group of different pouring temperature sufficient solidification process. We arrive at: the molten metal filling is steady, the coagulation is the smooth coagulation way from bottom to top. Along with pouring temperature's enhancement, the sufficient time and the setting time slightly have increase. The rising head plays strongly makes up shrinks the role. Overall evaluation, Determines under finally the metal mold gravity casting, the heat preservation rising head section for on small under big and the pouring temperature for 720℃is piston's best foundry technique.