Computer simulation of random and non-random second-phase particle distributions for both constant and varying particle size

Abstract

Mechanical properties of two phase materials, such as strength, ductility and toughness, depend on the size and distribution of the second phase. However, no methods are presently available to accurately quantify the homogeneity of the distribution of the second phase. Random and non-random second phase particle distribution have been simulated by computer and analyzed for various area fractions. Distribution of particles with a lognormal size distribution have been analyzed as well. Statistically sufficient number of particles for use in the model was determined and used for all simulations. Average first nearer neighbor spacing values for dilute arrays of particles approach those of Poisson distributions of infinitesimal points. As the particle density increases, the average spacing values approach those of hexagonal arrays. For low area fractions there is little distinction between random and non-random distributions, both from statistical and visual perspectives. For higher area fractions there is a discernible difference between the statistical data for random and non-random distributions, but the visual differences are more obvious. These observation hold for both constant size particles and particle with a lognormal size distribution.