Issue 57

A. Basiri et alii, Frattura ed Integrità Strutturale, 57 (2021) 373-397; DOI: 10.3221/IGF-ESIS.57.27

Figure 9: FE-SEM images of AlSi_N_T6 sample at a region of dispersed particles.

Figure 10: FE-SEM images of AlSi_N_T6 sample at highly clustered particles region.

Density Measurement It could be observed in Fig. 7 that some black tiny areas were present in the microstructure of AlSi_N_T6, which represents the micro-porosity areas. It has been indicated in several studies [7,49-50] that an enhancement in micro-porosity content would be achieved after nano-particles addition to the metal matrix, which results in mechanical properties degradation. Such a phenomenon was mainly attributed to poor wettability features of ceramic particulates [7,49], which stimulated the pore nucleation at nano-particles sites or agglomeration sites. The results of the pore measurement of both AlSi and AlSi_N_T6 using the Archimedes method are presented in Tab. 4. As it could be seen in Tab. 4, the porosity content of AlSi_N_T6 has increased in comparison to its counterpart AlSi alloy following the reports in the literature [7,49-50].

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