几何尺寸和物性参数对铝硅闭孔泡沫材料动态力学性能影响较大.消除材料自身尺寸效应的影响,采用落锤冲击实验方法对不同几何尺寸和物性参数的泡沫材料进行冲击实验,研究几何尺寸和物性参数对材料冲击吸能特性的影响.冲击实验结果表明:(1)材料几何高度增加,冲击作用下应变值减小,吸能量却有减小趋势,说明材料几何高度增大,极易产生材料孔壁破裂或整体失稳破坏,造成材料抵抗冲击载荷能力降低,立方体试件高宽比在1.0～1.5之间为宜,圆柱体试件高宽比为1.0～2.0时缓冲吸能作用发挥较好；(2)随着材料直径增大,抗压强度值增加,且峰值后降低幅值减小,应变值逐渐减小,说明材料直径的增加提高了抗压强度值,增强了材料抗冲击能力,但直径增加有一定界限,圆柱和立方体高宽比为1.0左右为宜；(3)材料密度越大,抗压强度值也越高,但峰值后的突降也越大；材料乳隙度越大,抗压强度值越小,材料易产生破坏,抗冲击能力也较低；材料孔径增大,抗压强度值降低,但变形量增加,受冲击载荷作用影响较大;(4)对比结果得到冲击吸能效果良好的泡沫材料合理物性参数,密度为0.35～0.70g/cm3,孔隙度为65％～87％,孔径为1.0～4.0mm.%Geometric size and physical parameters were the main factors of dynamic mechanical property of closed cell Al-Si foam materials. Using experimental method of concussion, the law of the influence of energy-absorption ability by geometric size and physical parameters was studied after eliminating the own effect of size. The research results are as follows: (l)With increase of the height of materials, the strain and absorbing energy value decrease, and it leads to wall burst and the overall instability or failure. The reasonable height-width ratio are 1. 0 ~1. 5 and 1. 0~ 2.0 for cube and cylinder specimens, respectively. (2) As the increase of the diameter, the compressive strength improves, and the strain values decrease. However, the diameter has a certain boundaries, the suitable height-width ratio are 1. 0 for cube and cylinder. (3)The bigger of the density, the larger of the compressive strength, but the peak reduce quickly. With the increase of porosity and diameter, the smaller the compressive strength value, and also it easy leads to destroy. (4)Contrasted by the results, the best physical parameters of density, porosity and diameter are 0. 35~0. 70g/cm3. 65%~87% and 1. 0~4. Omm, respectively.
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