Simulation of stress in reinforcements and stress-strain curve of SiCP/Al-2618 matrix composite

A 15% (volume fraction) SiC particle-reinforced Al-2618 matrix composite was selected to simulate its stress-strain curve and the stress in the reinforcing particles. The simulation was also carried out to two composites with hard matrix (T6 treatment) and soft matrix (T4 treatment). An analytical model was established based on Eshelby equivalent inclusion approach to do the simulation by introducing numerical secant moduli and tangent moduli scheme, respectively. The same modeling work was carried out by FEM analysis based on the unit cell model using a commercial ANSYS code. Through the comparison of the results between the simulation and experimental results, it is shown that the Eshelby model can predict the stress-strain curve of the composite with both hard matrix and soft matrix by introducing different numerical moduli, while the FEM model can not be used to simulate the stress-strain curve of composite with soft matrix. The stress in the particles is much higher than that in matrix shown by the simulation, which indicates that load transfer is the main strengthening mechanism for the particle-reinforced metal matrix composite.