Evaluation of the effect of adding carbon nanotubes on the effective mechanical properties of ceramic particulate aluminum matrix composites

•A novel micromechanical model is proposed to analyze the HAMCs.•Model estimations are consistent with the experimental data.•Adding CNTs can increase the elastic modulus of HAMCs.•Agglomeration and waviness of CNTs decrease the mechanical properties.•Formation of Al4C3 layer and alignment of CNTs improve the elastic modulus. In this study, a high-performance hybrid aluminum matrix composite (HAMC) reinforced with ceramic particles and carbon nanotubes (CNTs) is analyzed. A novel multi-step micromechanical approach, based on the Mori-Tanaka model and the generalized method of cell, is proposed in order to predict the effective elastic modulus and Poisson's ratio of the HAMCs. The influences of volume fraction, aspect ratio, waviness shape, alignment and agglomeration of CNTs, and ceramic particle volume fraction on the mechanical properties of CNT/ceramic particle-reinforced HAMCs are explored. Moreover, the role of aluminum carbide (Al4C3) which may be formed at the CNT/matrix interface in the mechanical behavior is micromechanically investigated. It is found that adding a small amount of CNTs into the microscale ceramic particle-reinforced aluminum matrix composites (AMCs) can significantly improve the effective mechanical properties of the resultant HAMCs. As compared to HAMCs, which contain the randomly dispersed CNTs, the alignment of CNTs into the HAMCs leads to a higher level of mechanical properties. However, the waviness and agglomeration of CNTs can decrease the HAMC elastic modulus. According to the obtained results, the CNT/matrix interfacial interaction may have significant effects on the effective properties of the particulate hybrid metal-based composites. The elastic properties estimated by the micromechanical model are compared to those measured by the experimental method. The outcomes of this research suggest that these hybrid metal-based composites, containing CNTs, have significant potential in diverse engineering applications as compared to the conventional metal-based composites.