An analytical model for elastic modulus calculation of SiC whisker-reinforced hybrid metal matrix nanocomposite containing SiC nanoparticles

In the present work, elastic modulus of a hybrid aluminum matrix nanocomposite (HAMNC) reinforced with silicon carbide (SiC) whiskers and SiC nanoparticles is analyzed. To this end, a new multi-scale analytical model is developed to calculate the effective elastic modulus of the HAMNC. The SiC nanoparticle aggregation into the HAMNC, frequently encountered in real engineering situations, is simulated. The elastic modulus of HAMNC estimated by the analytical micromechanical model is compared with that directly measured by the experimental method and a good agreement is found between the two sets of results. The effects of volume fraction, aspect ratio and dispersion type of SiC whiskers as well as volume fraction, size and aggregation degree of SiC nanoparticles on the HAMNC elastic modulus are extensively investigated. It is found that the elastic modulus of the SiC whisker-reinforced composite is significantly improved due to the addition of SiC nanoparticles. The results show that the nanoparticle aggregation has a damaging effect on the HAMNC elastic modulus. It is observed that the HAMNC elastic modulus can be enhanced by (i) increasing SiC content, (ii) aligning the SiC whiskers, (iii) increasing the SiC whisker aspect ratio (iv) decreasing the SiC nanoparticle size and (v) uniform dispersion of SiC nanoparticles into the hybrid nanocomposite. The reported results by means of the analytical model can be actually useful to guide design of general hybrid metal matrix nanocomposites with superior effective properties.