Kádár Csilla, Chmelík František, Ugi Dávid, Máthis Kristián, Knapek Michal
Department of Materials Physics, Eötvös Loránd University, Pázmány P. stny. 1/A, H-1117 Budapest, Hungary.
Department of Materials Science and Engineering, Faculty of Mechanical Engineering, Budapest University of Technology and Economics, Műegyetem rkp. 3., H-1111 Budapest, Hungary.
Materials (Basel). 2019 Oct 14;12(20):3342. doi: 10.3390/ma12203342.
Aluminum matrix (Al99.5) syntactic foam containing expanded perlite particles was produced using the pressure infiltration technique. The dominant deformation mechanisms during compression of this foam were determined by sequential k-means analysis of the acoustic emission data. Since the different deformation mechanisms were concurrently active even at small strains, successive unloading and reloading measurement was proposed for cluster identification. The repetitive unloading and reloading allowed us to identify two mechanical parameters, namely the unloading modulus and the loss for unloading-reloading cycles. Based on the correlations among the strain localization within the specimen, the acoustic emission results, the changes in these mechanical parameters, and the transition from quasi-elastic deformation to plasticity were revealed in this material.
采用压力渗透技术制备了含有膨胀珍珠岩颗粒的铝基（Al99.5）复合泡沫材料。通过对声发射数据进行顺序k均值分析，确定了该泡沫材料压缩过程中的主要变形机制。由于即使在小应变下不同的变形机制也同时起作用，因此提出了连续卸载和再加载测量来进行聚类识别。重复的卸载和再加载使我们能够识别两个力学参数，即卸载模量和卸载-再加载循环损耗。基于试样内部应变局部化、声发射结果、这些力学参数的变化之间的相关性，揭示了该材料从准弹性变形到塑性变形的转变。
