Grindability of Hipped Alumina Ceramics with Several Grain Sizes.

Multiple grain boundary transitions in ceramics: A case study of alumina

There is a growing body of the literature that suggests that there are grain boundary structures that exist in ceramic systems that are not predicted by bulk thermodynamics. Transitions between the various grain boundary structures are not well understood either experimentally or theoretically. This study identifies six different types of grain boundary structures present in the alumina system....

Mullite-alumina functionally gradient ceramics

Cracks free mullite-alumina Functionally Gradient Ceramics (FGC) have been obtained by sequential slip casting of Mullite-alumina slurries with diserent mullite/alumina ratios. These slurries were prepared with 65 % solids content and viscosities rangingpom 10 to 40 mPa.s. 7he presence of cracks perpendicular to the FGC layers have been attributed to residual stresses developed because of the m...

Surface Contamination of Alumina Ceramics by Carbon

Article history: Received: 01.05.2016. Received in revised form: 25.07.2016. Accepted: 06.09.2016. This study presents the results of investigating the cause of contamination of aluminum oxide ceramics (Al2O3) in the form of brown colored stain. Contaminated ceramic surfaces were examined with the scanning electron microscope (SEM) equipped with the Energy Dispersive Spectrometer (EDS). The res...

Hertzian Contact Damage in Porous Alumina Ceramics

A study has been made of Hertzian contact damage in compressive shear stress field beneath the contact area. The observed microcrack density increases with grain size, porous and dense liquid-phase-sintered aluminas. Indentation stress–strain curves show increasing nonlinearity as the implying a threshold microstructural scale for crack initiation. In contrast, the micromechanisms controlling f...

Grain Boundaries in Polycrystalline Alumina