EFFECT OF PARTICLE-SIZE DISTRIBUTION AND MIXING HOMOGENEITY ON MICROSTRUCTURE AND STRENGTH OF ALUMINA COPPER COMPOSITES/

The powder mixtures of Al2O3/CuO with a variation in particle size dis tribution and mixing homogeneity were prepared using different milling process. The mixing homogeneity was quantitatively determined by the coefficient of variation. Homogeneous microstructure and a high fractu re strength of the hot-pressed Al2O3/Cu composites could be achieved u sing the powder mixture with narrow size distribution and high mixing homogeneity. The relationship between mixing homogeneity anal properti es was discussed based on the role of unevenly dispersed second phase for the matrix grain growth and for the local variation of mechanical characteristics. (C) 1998 Acta Metallurgica Inc.