Resistance to frost action and microbiological corrosion of novel ceramic composites

This work illustrates the prediction of frost action mechanisms on ceramic compacts, as well as their biocorrosion resistance to fungus action. The ceramic compacts were produced from two raw materials: coal fly ash (40 wt. %) and clay material (60 wt. %). The ceramics models were made in laboratory conditions by pressing (P = 45 MPa), drying (105?C, 3h) and sintering (1100?C, 1h; heating rates 3?C/min and 10?C/min.). The mechanisms responsible for the deterioration of the designed ceramic compacts were defined based on the values of the total porosity, pore size distribution, pore critical radius and the Maage factor, as well as on the values of water permeability. The process of biocorrosion was investigated by using Aspergillus niger fungus as a model microorganism. The different degrees of fungus colonization on the designed compacts were comparatively analysed based on the results of the Scanning Electron Microscopy investigation. The gained results are encouraging as they show that the utilization of fly ash (40 wt. %) in ceramic composites is possible without significantly deterioration of their durability (frost action and microbiological corrosion resistance) compared with the ones whose production was based only on clay material.