铝合金自行车前叉件压铸工艺的数值模拟分析

Numerical Simulation of Die-casting Process for Al Alloy Bicycle Front Fork

依据自行车前叉铝合金压铸件的结构特点设计两种方案的浇注排溢系统。基于有限差分方法的铸造分析软件ADSTEFAN,对两种方案温度布和凝固过程进行模拟分析,并对铝合金自行车前叉件模具结构进行了设计和优化。模拟表明,长U型类压铸件的浇口位置设计在模具中间部位,既可使模具结构紧凑,又可保证模具的热平衡;采用对称结构梳状内浇口的同时要考虑内浇口分布位置及疏密,将直接影响充填及凝固过程中材料的质量、能量的均衡性。综合以上因素建立了该压铸件优化模具并试制了一批铸件,所获铸件质量良好,与模拟结果吻合。

Two programs of gating system were designed according to the structural characteristics of bicycle front fork.The temperature distribution and solidification process was simulated by ADSTEFAN,then the die design of the fork was optimized.The results show that the inner gates of U type irregular casting is set in the middle of the die,which can bring benefits such as simplifying die structure,ensuring thermal balance of the die.Using symmetric comb-type inner gate,the location and density of inner gates can influence the mass and energy distribution of melt during filling and solidification process.Finally the optimized die of the fork was made and a batch of casting was produced.The castings possess good quality and are in good agreement with simulation results.