Corrosion potential and electromagnetic shielding effectiveness of geopolymer tiles produced with waste metal particles

This study is related to the production of special geopolymer specimens, where high effectiveness is provided in terms of electromagnetic interference (EMI) shielding and corrosion resistance. The study is important for the preparation of silica fume/slag based geopolymers by using waste steel and iron powder as a partial substitute for slag aggregate and thus to provide an effective solution to the disposal problems of waste metals. The electromagnetic interference shielding effectiveness (SE) of geopolymer tiles of 7.6 ± 0.1 mm thickness with different metal contents was measured at 4.9–7.05 GHz. Corrosion activity was monitored by measuring the half-cell potential of copper/copper sulphate (Cu/CuSO4) on specimens kept under controlled laboratory conditions for a period of 90 days at %60 relative humidity according to ASTM C876. In addition, anextensive evaluation of the optimization research on the design and proportion of mortar mixtures is presented here. EMI shielding effectiveness of slag based geopolymer tile with 10% steel particles has been determined as 26.1 dB in the frequency range 4.9–7.05 GHz. The results show that the shielding effectiveness reached a maximum of 23.1 decibels (dB) for geopolymer tiles in 40% iron powder content. Also, from experimental results, it was learned that geopolymer specimens with high slag content as binders in the mixtures showed better corrosion resistance.