Influence of the Particle Arrangement and Type on the Deformation of Dispersion Hardened Aluminum Alloys.

The admixture of powders to the aluminum melt can be regarded as a direct process for the production of dispersion-hardened materials. A great obstacle to obtaining the desired uniform particle distribution is the poor wettability of most types of powders. Only at very high temperature (about 1400 degree C) with a very high expenditure of energy, is the blending process to any extent successful. A uniformly distributed particle dispersion is produced by additional intensive mixing. By this means, in the case of AlSiC, a strength similar to that of dispersion hardened materials produced bypowder metallurgy can be attained. The ductility of particle-hardened alloy systems cannot be strictly related to strength. The nature of the particle bonding or the adhesion of the particle to the matrix is of far greater importance as far as breaking elongation is concerned.