Abstract:

In this study, the influence of a reduction of both grain size and flaw size by hot isostatic pressing (HIP) on mechanical preperties of Al₂O₃-ZrO₂(ZTA) composites and as well the dinsification behavior in HIP are investigated. It is shown that the high strength (950MPa) and high toughness ( 0.5MPa √m) could be obtained by a high temperature-short time HIP treatment, and the main effect of HIP is in the elimination of flaws rather than in the reduction of gram size, i.e. defect healing; the densification rate in HIP is controlled by different mechanisms at low and high temperatures(1400℃ and 1600℃ ),i.e. by relative movement of adjacent grains and lattice diffusion.

Key words: HIP, grain size, flaw size, toughness, densification rate