Aging behavior and thermal expansion of novel Pb alloys reinforced with fly ash cenospheres composite foams

Aging response of novel Pb alloy-based hybrid composite foams for light weight batteries is investigated in this work. Severe aging conditions were selected to simulate the battery grid during the lifetime of the battery. It was found that the values of hardness as well as the peak hardness of the composite foams were higher than those of Pb alloy matrix foam. The presence of cenospheres in the composite foam reduced the time to attain the peak hardness, comparing to the Pb alloy-based foam. The hardness of the overaged Pb alloy matrix foam was too low, but the hardness of overaged composite foams remained high even after several aging days at 90 °C, indicating that the existence of cenospheres hindered the negative effects of overaging process on Pb alloy matrix foam. The coefficients of thermal expansion (CTEs) of the Pb composite foams were lesser than the CTEs of the Pb alloys due to the presence of the cenospheres in the composite foams.