Numerical validation of thermal conductivity of Al6061 based hybrid nano metal matrix composite filled with nanoparticles of Ni and Cr

Aluminum composite matrix materials are regarded as the most popular type of composite materials. Metal matrix composites made of aluminum have better mechanical and thermal properties, including a higher strength-to-weight ratio, tensile strength, hardness, and a low coefficient of thermal expansion. In various types of applications viz., automobile, aviation, the thermal characterization of aluminum metal matrix composites has increased. Thermal conductivity as a function of temperature, thermal diffusivity, and the thermal gradient is one of the essential thermal characteristics of aluminum metal matrix composites needed to understand the material's behavior. The current work evaluated thermal conductivity as a product of thermal diffusivity, density, and specific heat for Al6061/Ni/Cr hybrid nano metal matrix composites from 50°C to 300°C. Al6061 based metal matrix composite reinforced with varying wt.% of Ni and Cr nanoparticles whereas fixed wt.% of graphene and Mg added to improve thermal conductivity, self-lubrication, and wettability. Thermal diffusivity, specific heat, and density were evaluated using laser flash apparatus (LFA 447), differential scanning calorimetry (DSC), and Archimedes principle, respectively. Results revealed that the thermal conductivity of fabricated composites increases with Ni, Cr, Mg, and graphene nanoparticles. With further expansion of reinforced particles of Ni and Cr, the thermal conductivity decreases. Finite element analysis (FEA) has been conducted to determine the thermal gradient and thermal flux using experimental values such as density, thermal conductivity, specific heat, and enthalpy at various temperature ranges to validate the experimental results.