Quantitative analysis of the effects of particle content and aging temperature on aging behavior in B4C/6061Al composites

Abstract This work gives a quantitative analysis of precipitations in B4C/6061Al composites with B4C volume fraction of 3% and 12% and the impacts of B4C particles volume fraction and aging temperatures on aging behavior. These aspects of microstructural evolution were unveiled through differential scanning calorimetry (DSC), transmission electron microscopy (TEM) and Brinell hardness measurements. It is shown that the aging kinetic is considerably accelerated with the increase of ceramic particle volume fraction. With the aging temperature increasing from 130 °C to 190 °C for B4C/6061Al composites when the particle volume fraction is 3%, the time to reach peak-aged state decreases from 60 h to 5 h. Compared with commercial 6061Al alloys, the addition of B4C particles inhibits the formation of G.P. zone, and changes the order of precipitations in B4C/6061Al composites. Importantly, the number density, cross-sectional area and volume fraction of precipitations in the matrix were quantified in order to characterize the effect of B4C particle volume fraction and aging temperatures on the aging behaviors in B4C/6061Al composites.