铝合金半固态触变充型过程的计算机模拟

分析半固态AlSi7Mg合金触变充型过程中各个阶段浆料的压力和速度变化特征,建立耦合半固态表观粘度的三维流场数学模型,在考虑半固态边界条件和气体阻力方程基础之上,采用SOLAVOF法对铝合金件的触变充型过程进行模拟计算.结果表明, 入流速度大小对半固态浆料充填流态有显著影响.小的入流速度浆料充填流态倾向于采用平稳充型,同时气孔等缺陷产生倾向也小.与刹车泵体轴向注入工艺相比,在一定入流速度下,采用径向注入工艺成形阻力较小,充型中不会出现充不满的铸造缺陷.上述模拟结果与实际相吻合.

Simulation on Filling Process of Semisolid Aluminum Alloy Casting

Based on the behavior of pressure and flow velocity during semisolid A1Si7Mg slurry filling processes, a three dimensional model of slurry flow coupled with apparent viscosity is established. Relating to boundary condition and cavity air pressure, simulation on semisolid aluminum alloy casting has been investi- gated with the help of the SOLA-VOF algorithm. It is shown that flow velocity of semisolid slurry have mark effects on the flow patterns. Lower flow velocity result in mold filling steadily and prevent gas porosity. Under certain flow velocity, using process in which mold filling along the radial lead to lower filling resistance when compared with the axial, none of these castings have defects. Finally, simulation results is in agreement with the experimental results.