Microstructural parameters of Cu-Al{sub}2O{sub}3 dispersion strengthened materials

摘要

Microstructural parameters of Cu-Al{sub}2O{sub}3 dispersion strengthened materials were evaluated in the paper. Using the extraction carbon replica for analyses of Cu-Al{sub}2O{sub}3 (1 - 10 vol.%) system, it was shown that the majority phase of dispersoids were the Al{sub}2O[sub}3 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 Al{sub}2O{sub}3 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 Al{sub}2O{sub}3 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 σ{sub}θ.