Modern automobiles require materials with high thermal properties and less weight for extraordinary performance. Metal matrix composites (MMCs) possess the mechanical properties required for automobile applications. The present work focuses on developing a mathematical model using the finite-difference technique to examine the cumulative and individual influence of silicon carbide (SiC)/aluminum oxide (Al2O3) nanoparticle weight percentage on the MMCs’ time–temperature history curve. The thermophysical properties of MMCs are considered to be isotropic and homogeneous and are calculated using the mixture rule and the Maxwell model. The results reveal that increment in the weight percentage of the nanoparticles (silicon carbide/aluminum oxide) makes the time–temperature history curve steeper. The cumulative effect of the nanoparticles results in a less steep time–temperature history curve compared to the individual nanoparticle, indicating a decreased solidification rate due to low effective thermal conductivity. The two thermal conductivity models show the same time–temperature history curve due to less deviation in the thermal conductivity of MMCs. The mathematical model developed in the present work predicts the time–temperature history curve accurately which matches well with the experimental results.