CHIEKO YAMAGATA

Resultados de Busca

Agora exibindo 1 - 1 de 1

Micrograded ceramic-metal composites
2019 - RESTIVO, THOMAZ A.G.; BECCARI, RAFAEL F.; PADILHA, WELLINGTON R.; DURAZZO, MICHELANGELO; TELLES, VICTOR B.; COLETI, JORGE; YAMAGATA, CHIEKO; SILVA, ANTONIO C. da; SUZUKI, EDUARDO; TENORIO, JORGE A.S.; MELLO-CASTANHO, SONIA R.H.
The article shows new designed cermets and processes concerning primary to applications as thermal insulation materials with low emissivity. A new projected microstructure was obtained where dense regions (micropellets) rest inside the main porous pellet. The feature resembles a frozen hypercube, therefore such architecture is called hyper-pellet/ cermet. The processing method to obtain the hyper-cermet is based on sequential tape castings and sintering techniques. Ni-zirconia lamellae were prepared by a special mechanochemical process followed by sintering, which remain inside the main pellets as a dense region. The whole pellet is turned to be porous by employing pore-forming additives. All the constituents and porosity shapes are aligned along the disc/ flake planes. Thermal conductivity is estimated for the materials up to 800 °C by a flash diffusivimeter. Ceramographic analyses show graded density regions with directional constituents and pores. Applications of such materials are foreseen as temperature insulation materials and thermal radiation shields.