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The present study was an attempt to examine the effects that adding silica aerogel (SA) nanoparticles to epoxy would exert on its mechanical, vibrational, and morphological properties. Neat epoxy was consecutively combined with 1, 2, and 4 wt% of SA nanoparticles. A number of tests of mechanical properties were then performed on the samples, including tests of tensile, bending, compressive, dynamic mechanical thermal, hardness, and Izod impact. Vibration and water uptake tests were also conducted on the samples. The highest modulus and strength values were found in the nanocomposite sample with 4 wt% of SA, and the highest toughness and elongation values were detected in the sample with 1 wt% of SA. Furthermore, adding the SA nanoparticles to the epoxy improved the energy absorption and hardness of the epoxy matrix. The findings from the tests of dynamic mechanical thermal and vibration properties demonstrated that, with an increase in the nanoparticles content in the samples, the values of storage modulus and natural frequency increased while the values of tan δ and damping ratios decreased. A comparison between the values of natural frequency from the vibration test and the values from the Euler–Bernoulli beam theory showed a good agreement between the theoretical and experimental results.

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A bulk hybrid composite to be potentially used as a foam precursor was produced in this study. TiH2 powder particles along with different concentrations of SiC were mixed with pure Al particles and consolidated through the spark plasma sintering (SPS) method. Bulk samples with nearly full density were successfully produced using the SPS method. During the consolidation process, no additional phases were found within the ceramic particles/matrix interfacial region. Using the ceramic TiH2 and SiC particles as the reinforcement cause notably strengthened the pure Al matrix (37% higher yield strength) without adversely affecting the plasticity, helping retain strain to fracture of about 50% for the sample. The yield strength of the samples was quantitatively approximated by examining their strengthening mechanisms via a number of simplified models available in the literature. The analyses found grain boundary and dislocation strengthening to be the most effective mechanisms for enhancing the strength of the samples; it was also found that the difference between the approximated and experimentally obtained overall yield strength was negligible.