Production and Characterization of Glass-Ceramic Cellular Structures by the Replication Method

摘要

Glass-ceramic materials were used as a possible material for the production of cellular structures. They were produced by the replication method using polyurethane (PU) foams as templates (9 and 33 pores per inch ppi). LZSA (Li_2O--ZrO_2--SiO_2--Al_2O_3) parent glass powder was used to infiltrate the PU foams. Heat treatment of the samples was performed in a twostage process. The first stage at around 450?C consists of slowly decomposing and burning out the PU support. The second stage, at 750?C, is for sintering, densification and crystallization of the parent glass powder to form glass-ceramic. Several parameters where characterized. Bulk density ρ (geometric methods) and real density ρs (picnometry) was determine. Relative density ρ /ρs and porosity ε (via relative density) were measured for both types of the LZSA and PU foams. Image analysis was used to determine cell area and cell diameter distribution and porosity ε (via image analysis). The morphology was also determined. Glass-ceramic materials were introduced in the production of ceramic cellular structures following the replication process. The employment of glass-ceramics is a new application in the field of filters and cellular materials with low sintering temperatures. Open cell polymeric template foams are essential in order to obtain open ceramic replicas. To characterize cellular structures adequately various characterization techniques must be used. More than one technique can be used to analyze the same property, allowing self experimental corroboration.