The effect of powder forming method on the pull-out flaw populations observed on polished surfaces of alumina ceramics

Quantitative image analysis was used to study the effect of the powder forming method on the population of pull-out flaws for polished surfaces of dense alumina ceramics. By comparing the area fractions, the size distributions and the extreme values of the pull-out areas it was concluded that slip casting with dispersed slips resulted in significantly fewer and smaller pull-outs compared to slip casting with flocculated slips or powder pressing. The implications of these observations for the effect of the powder forming method on the strength of alumina ceramics are discussed.