Processamento e caracterização de espumas cerâmicas de microfibras naturais de sílica amorfa obtidas pelo método de réplica

Karina Donadel; Jerônimo Gomes Moraes; Carlos Renato Rambo; Dachamir Hotza; A. P. Novaes de Oliveira

doi:10.5585/exacta.v6i1.813

Authors

Karina Donadel UFSC
Jerônimo Gomes Moraes UFSC
Carlos Renato Rambo UFSC
Dachamir Hotza
A. P. Novaes de Oliveira UFSC

DOI:

https://doi.org/10.5585/exacta.v6i1.813

Keywords:

Cerâmica. Espumas cerâmicas. Método de réplica. Microfibras de sílica amorfa.

Abstract

Cellular ceramics are brittle materials containing high porosity and constituted by a regular and tridimensional arrangement of hollow cells. The great interest on this group of materials is related to their specific properties such as low density, low thermal conductivity and high permeability. In this work, ceramic foams were processed by the replication method. Commercial polyurethane foams with different cell sizes were used to produce foams constituted by microfibers of natural amorphous silica. The polymeric foams were immersed in the ceramic suspension (natural amorphous silica fibers - NASF, bentonite, sodium silicate and water) and then dried and heat-treated for consolidation. The polymeric foam was burned out at 400°C and sintering was carried out at 1150° C for 15-120 min. The obtained sintered samples were subjected to mechanical strength tests, so that compression strength values between 6 and 260 kPa were obtained.