Multiscale modeling and prediction of elastic properties of MWCNT- and RHA-reinforced AlP0507 matrix composite

The objective of this study is to utilize numerical modeling techniques to forecast the performance of a novel metal matrix composite and speed up the experimental testing process by reproducing the unique features observed at the micro-scale of the composite material. The matrix material chosen for this study was aluminum P0507 alloy, with multi-walled carbon nanotube (MWCNT) and rice husk ash (RHA) selected as the reinforcements. The reinforcement loading was varied from 1 to 9 vol.%. The representative volume element model in corroboration with the DIGIMAT-FE software was utilized to model, simulate and assess the performance of these composites across different volume fractions and orientations. Both the modulus, elastic and shear, increased monotonously with increase in the CNT and RHA content, whereas the Poisson’s ratio decreased with increase in the reinforcement loading; the changes being more evident in CNT-reinforced composites. On one hand, highest value of E₁ was found in case of aligned inclusions, on the other hand, the highest value of E₂ and E₃ was found for composites containing 2D random orientation type inclusions. As far as shear moduli are concerned, the highest value of G₁₂ was found for 2D random orientation type, and the highest value of G₂₃ and G₁₃ was found in case of 3D random type orientation. The elastic moduli and shear moduli followed the following trend: E₁ > E₂ > E₃ and G₁₂ > G₁₃ > G₂₃. The values of elastic as well as shear moduli for hybrid composite, Al-9 vol.% (CNT + RHA), were found to be higher than that of Al-9 vol.% RHA. For instance, the value of 2D-oriented E₁ increased from 77.15 to 78.40 GPa, and the value of aligned G₁₃ enhanced from 29.17 to 29.45 GPa. Therefore, it can be concluded that hybrid composites give luxury to fabricate components with tailored properties at a lower cost.