泡沫铝的单向压缩行为及其吸能性

在SUNS电子万能材料试验机上对国产工业用泡沫铝材料进行准静态单向压缩试验，分析试件尺寸、材料相对密度及泡孔尺寸对材料静态压缩性能及吸能性能的影响。结果表明，在准静态条件下，泡沫铝泡孔孔径越大，弹性模量与塑性模量越小、屈服强度越大．但当相对密度超过32％后，塑性压垮强度却因泡孔孔径增大而降低，弹性模量在相对密度约为30％时出现拐点。孔径大吸能效率高。试件高度减小，压缩应力-应变曲线中的塑性平台长度缩短，且当试件高度小于10mm肘，塑性压垮强度明显提高。理想吸能效率最大值随试件高度增加而提高。泡沫铝微结构中的微缺陷引起材料压缩性能的降低。

Mechanical Behavior and Energy Absorption Capacity of Aluminum Foam under Uniaxial Compression

The effects of the specimen height, relative density and cell size of one domestic commercial aluminum foam product on the compressive properties are analyzed by quasi-static and uniaxial compression test with SUNS Electron Universal Material Testing Machine. The results show that the larger the cell size of aluminum foam, the less the elastic and plastic modulus, and the higher the plastic collapse strength, but the plastic collapse strength reduces with the increase of the cell size while the relative density is over 32 %, under condition of quasi-static and uniaxial compression. The inflection point of the elastic modulus appears at relative density 30 %. And the energy absorption efficiency is high if the cell size of aluminum foam is large. The plastic yield plateau length in compressive stress-strain curves of aluminum foam is decreased with the decrease of the specimen height, when the specimen height is less than 10mm, the plastic collapse strength is remarkably increased. The value of the maximum energy absorption efficiency is increased with the increase of the specimen height. The microstructure defects and the harmful remains during manufacturing in the foam result in the decrease of the aluminum foam compressive properties.