steel slag filled phenolic thermal protection system; a new application for steel slag as a flame-retardant additive

In this study, a fire protection composite based on the phenolic resin )as matrix phase( and steel slag (ss), an industrial waste of khuzestan steel company (ksc) )as filler( was developed. novolac resin was used as phenolic type resin as binder. the novolac/ss (n/ss) composites were prepared by different ss solid content (10, 15, and 20 wt.%). the microstructure, mechanical strength and flame stability of n/ss composites were investigated. the results indicated that the compressive strength of flame-resistant composites was in the range of 49.5-45.8 mpa and decreased with ss solid content. the flame test showed that the addition of ss could enhanced the flame retardancy of composites. it could be attributed to the formation of metal oxides at the exposed surface and also increasing of char layer density. according to this study, ss could be used as a low price and desirable filler in the structure of polymeric thermal protection systems in the severe and high temperature applications such as heat shields and insulators.