Effects of iron powder on properties of geopolymers subjected to different curing regimes

Silica fume, slag and iron powder are by-products from various industries. In parallel with development of industrial technology, it is also known that these by-products which cause rapid pollution of the environment are also harmful to human health because they are easily respirable. For this reason, a series of experiments were carried out to determine physical and mechanical properties on samples prepared using different blend designs to examine the effect of factors such as curing conditions, binder type and waste iron powder content. Percentages of iron powder added to replace the aggregate are 10%, 20%, 30% and 40% by volume of slag aggregate. It was observed that the substitution of 30% by volume iron powder instead of slag in geopolymer mortars is the most effective in increasing splitting tensile strength. For 40% partial replacement of fine aggregates with iron powder, increases in compressive strength and flexural strength of slag-based mortars were 7.2% and 43.4%, respectively, compared to mortar without iron powder at 60°C curing conditions.