Carbon fiber waste incorporation in blast furnace slag geopolymer-composites

Abstract

This work evaluates the properties of geopolymer-composites based on blast furnace slag with additions of a carbon fiber waste coming from the aircraft industry. Two parameters were considered: slag/waste ratio (100/0, 80/20 and 60/40) and nature of activating solution (8 M NaOH and sodium silicate). Open porosity and compressive strength were analysed. Geopolymers were also subjected to a sulphuric attack and thermal resistance test (compressive strength after 105, 300, 500 and 700 C was assessed). Porosities increased and compressive strengths decreased as the slag was replaced by the carbon fiber waste. A positive effect of the carbon fiber waste on the acid attack was observed mainly due to the created porosity which could generate space to calcium-sulphate products precipitation. CFW incorporation improved the thermal resistance since higher porosity could provide channel to increase heat dissipation.