PSI - Issue 27

Hammar Ilham Akbar et al. / Procedia Structural Integrity 27 (2020) 62–68 Akbar et al. / Structural Integrity Procedia 00 (2019) 000 – 000

65

4

3. Results and discussion 3.1. XRD result

The XRD sea sand results are shown in Fig. 3. The XRD results show that sea sand contains ceramic compounds SiO 2 and FeMgO 4 . The presence of SiO 2 ceramic compounds shows that sea sand can become engineering purpose materials (Bisane et al., 2015).

Fig. 3. XRD result of sea sand.

3.2. Density and porosity The theoretical density and porosity calculations on the composite refer to the rule of mixture (ROM) according to Eqs. 1 and 2, respectively (Kannan and Ramanujam, 2017). ρ theoretical = ρ m φ m + ρ r φ r (1) Where φm and φr represent the weight fraction of the matrix and the reinforcing particles, and ρm and ρr symbolize the density of the matrix and the density of the reinforcing particles. The density of the experiment is calculated based on Archimedes' principle = ( ℎ − ) ℎ × 100% (2) A comparison of density and porosity of composites is shown in Figs. 4 and 5, respectively. The Composite density with sea sand reinforcement has a higher density of 2.67 g/cm 3 , and then the lowest density is obtained on composites with alumina reinforcing particles 2.53 g/cm 3 . Inappropriate with density, the lowest porosity is found on composites with sea sand reinforcement particles with 0.84%, while composites with alumina reinforcing particles have the highest porosity of 6.74%. Lower porosity resulted in composite with sea sand reinforcing due to density of sea sand 2.5 g/cm 3 (Hilman et al., 2014), lower than alumina and SiC. Particles with higher density tend to sink to the bottom of the crucible and initiate the porosity (Bihari and Singh, 2017). The occurrence of porosity reduces the density and mechanical properties of the material.