Effect of particle size on microstructure and strength of porous spinel ceramics prepared by pore-forming in situ technique

Abstract

The porous spinel ceramics were prepared from magnesite and bauxite by the pore-forming in situ technique. The characterization of porous spinel ceramics was determined by X-ray diffractometer (XRD), scanning electron microscopy(SEM), mercury porosimetry measurement etc and the effects of particle size on microstructure and strength were investigated. It was found that particle size affects strongly on the microstructure and strength. With decreasing particle size, the pore size distribution occurs from multi-peak mode to bi-peak mode, and lastly to mono-peak mode; the porosity decreases but strength increases. The most apposite mode is the specimens from the grinded powder with a particle size of 6•53 μm, which has a high apparent porosity (40%), a high compressive strength (75•6 MPa), a small average pore size (2•53 μm) and a homogeneous pore size distribution.

Design and Development of Potential Tissue Engineering Scaffolds from Structurally Different Longitudinal Parts of a Bovine-Femur

“…In this context, Archimedes' principle have been exploited widely and precisely in several explores to measure the density and porosity284041. Figure 6 depicts the changes in the trends in bulk density (i.e., mass per unit volume of a specimen), open porosity (i.e., ability to hold air or fluid by open voids present in a specimen), and close porosity (i.e., empty space without connecting via any open path or channel present inside a specimen) with the temperature at which the FBCBs were heat-treated (see Table S3 in Supplementary Information).…”

Lightweight cordierite–mullite refractories with low coefficients of thermal conductivity and high mechanical properties

“…Traditionally, lightweight refractories, fabricated by a conventional powder-processing route with the incorporation of some pore-forming agents, have a pore structure with large pore size and inhomogeneous pore size distribution, and then have low strengths and low thermal-shock resistances, which limited the application of traditionally lightweight refractories for working lining of high-temperature furnaces. 2 Cordierite(2MgO•2Al 2 O 3 •5SiO 2 ) possesses a low thermalexpansion coefficient, an excellent thermal-shock resistance and chemical stability at elevated temperatures, and then the porous cordierite ceramics have attracted more attention. [3][4][5][6] However, the porous cordierite ceramics are not suitable for the working lining of furnaces, because (1) the homogeneous microstructure of porous ceramics is harmful to the thermal-shock resistance; (2) the mechanical properties of cordierite material are poor.…”

Low cost porous alumina with tailored gas permeability and mechanical properties prepared using rice husk and sucrose for filter applications

“…25 Yan et al reported fabrication of porous cordierite with interconnected pores through an in-situ technique, and the permeability of sample with a porosity of 40.3% was 2.31 x 10 -12 m 2 . 26 A comparison of permeability of samples having above mentioned two types of pore structures with almost similar porosity shows that those with interconnected pores have relatively higher gas permeability. Thus, porous ceramics with interconnected pores and adequate strength can be preferred for filter application.…”