Abstract
In the present study, the effect of cobalt oxide on the densification of Al2O3-YAG composite nanopowder was investigated. An amorphous nanopowder was synthesized and crystallized to Al2O3-YAG after heat-treatment via a solid-state reaction. The average particle size of heat-treated powder at 800?C was about 80 nm. Cobalt oxide improved the sintering rate of Al2O3-YAG composite nanopowders and promoted grain boundary mobility. Cobalt oxide doping increased the ratio of densification/grain growth rate. The activation energy for grain growth decreased from 590 to 485 kJ/mol by adding cobalt oxide to the composite nanopowder.
Highlights
Alumina is one of the most widely used ceramic because of its good mechanical properties such as hardness, good corrosion resistance and high temperature insulation
The purpose of this study was to investigate the effect of cobalt oxide on densification, grain growth and microstructure of Al2O3-YAG composite nanopowder prepared by an aqueous sol-gel method
It was found that cobalt oxide-doping increased the ratio of densification/grain growth rate
Summary
Alumina is one of the most widely used ceramic because of its good mechanical properties such as hardness, good corrosion resistance and high temperature insulation. The combination of YAG with alumina leads to development of composite materials for structural applications with excellent mechanical properties. The sintering of Al2O3-YAG composite requires high temperatures and long times [5]. First approach is application of alternative consolidation techniques, such as hot pressing or spark plasma sintering. In nano-scale form, as the powder particle size decreases, the amount of lattice defects, grain boundary and surface area increase, results in densification at lower temperatures [6,7]. It is well known that ceramic microstructures and its mechanical properties strongly depend on the presence of dopants [8]. Various investigations revealed that cobalt oxide is a suitable additive for
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
