In order to obtain dense Si3N4 bodies from low cost powder using LiYO2 additive for liquid phase sintering the effects of different types of homogenization procedures (attrition, ball and vibratory milling) are studied. Backscattered electron imaging was used to examine the homogeneity of the yttrium distribution in the green compacts. Homogeneity, as well as grain size distribution, specific. surface area and oxygen content show an influence on the sintered density. The main influence being the quality of particle packing. It is found that attrition milled powders give the best sintering results.