Microstructural Parameters of Cu-Al2O3 Dispersion Strengthened Materials

Microstructural parameters of Cu-Al2O3 dispersion strengthened materials were evaluated in the paper. Using the extraction carbon replica for analyses of Cu-Al2O3 (1-10 vol.%) system, it was shown that the majority phase of dispersoids were the Al2O3 particles of 60 nm average diameter, which were distributed individually or in clusters of #~380 nm size. The real volume fraction estimated on the metallographical cross sections of coarser Al2O3 phase was slightly different than the nominal volume fraction. The overestimation resulted from the presence of inclusions, especially the FeO from the milling environment. The distribution of Al2O3 particles in the matrix estimated by three methods (quadrant count method, polygonal method, and by using the interparticle distances) showed that particles distribution in A material (1 vol.%) is very close to the Poisson point process (PPP). Particles distributions in materials B and C (8 and 10 vol.%) exhibit the features of regularity what was proved mainly by the parameter of spherical contact distance *sthetaDT.