The Influence of Porosity on the Elasticity and Strength of Alumina Ceramics

Abstract

this work investigates the behavior of porous alumina ceramics (within the porosity range of 18% to 70%) when subjected to deformation by compression and shear. the analysis of straindeformation curves showed that there was a transition from a typically brittle state for relatively dense ceramics (≤20% porosity), to a pseudo-plastic one with a high rate of porosity (above 50%). the values of the modulus of elasticity, shear modulus and Poisson's ratio decrease with an increase in volume in the pore space of Al 2 o 3 ceramics, which correlates with the appearance of multiple cracking during the deformation of ceramics with a high level of porosity.

Structure and properties of porous ceramics obtained from aluminum hydroxide

“…The pore structure of ceramics and morphology of the powder was investigated using scanning electron microscope (SEM) Philips-SEM 515 and optical microscope. The mean pore size of ceramics and the powder particles were calculated by the secant method [5].…”

“…To form a multi-level pore structure without addition of pore-former one can use the method of decomposition of components, for example, the hydroxides to oxides, accompanied by the release of gas and, as a consequence, the formation of porosity [4]. This method based on the decomposition of aluminum hydroxide to the oxide has been known for a long time [5], but there is no data on the regulation of the pore space volume and the dependence of the pore space formation sintered at different temperatures, particle size of initial powders, as well as no data about dependences of the strength of the ceramic with changing of porosity.…”

Synthesis, Characterization and Rheological Properties of Alumina-Zeolite Mixtures

“…The research development in the field of ceramic industries is becoming a more popular and fast-growing field of material science [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Aluminium oxide (alumina; Al2O3) has superior thermal, mechanical, physical and chemical properties when compared with many other ceramics materials.…”

Modelling and Experimental Testing of Hybrid Joints Made of: Aluminium Adherends, Adhesive Layers and Rivets for Aerospace Applications

“…thin interface layers, [9][10][11][12][13], (3) thermal barrier coatings in the form of sequence of ceramic layers covering turbine blades (e.g. [14][15][16]), (4) 2 structural materials joined by adhesive e.g. [17][18][19][20][21][22].…”