基于渗流法的泡沫铝细观结构模型研究

Research on Micro Structural Model of Open-Cell Aluminum Foam Based on Infiltration Casting Methods

泡沫铝能在较低的流动应力下产生较大的塑性变形,是一种优异的缓冲吸能材料.渗流法是目前较成熟的工业化生产开孔泡沫铝的方法之一,基于该方法的工艺流程,采用蒙特卡罗法和重力堆积法建立了泡沫铝的细观结构模型.结合SPH算法在应变率范围为10-10 000s-1内对泡沫铝的压缩行为进行数值模拟,并分析了泡沫铝的变形失效模式.结果表明：基于渗流法的数值模拟方法可以反映泡沫铝的动态压缩过程,并且高应变率下泡沫铝的变形模式与中低应变率相比存在明显的差异.

Aluminum foam is an excellent energy absorption material which can produce large plastic deformation at low flow stress. Infiltration casting method is one of the mature methods of producing open-cell aluminum foam industrially. Based on the technological process of this method, a micro structural model of open-cell aluminum foam was built by Monte Carlo method and gravitational sedimentation method. Combined with SPH algorithm, compression behavior of aluminum foam was studied nu- merically from low strain rate 10 s-1 to high strain rate 10 000 s-1. Then deformation and failure mode was analyzed. The results show that the numerical simulation method based on the infiltration casting methods of manufacturing open-cell aluminum foam can reproduce the dynamic compression process and compared to middle and low strain rate, there is a significant difference of deformation and failure mode at high strain rate. Key words： open-cell aluminum foam; micro structure; infiltration casting methods; numerical simulation