The present disclosure concerns composite material having improved strength at elevated temperatures. The composite material comprises a matrix of an aluminum alloy (comprising, in weight percent, Si 0.05-0.30, Fe 0.04-0.6, Mn 0.80-1.50, Mg 0.80-1.50 and the balance being aluminum and unavoidable impurities) as well as particles of a filler material dispersed within the matrix. The matrix can optionally comprise Cu and/or Mo. In some embodiments, the composite material comprises, as a filler material, B4C as well as an additive selected from the group consisting of Ti, Cr, V, Nb, Zr, Sr, Sc and any combination thereof. The present disclosure also provides processes for making such composite materials.