Novel geopolymer based composites reinforced with stainless steel mesh and chromium powder

In this study, two novel geopolymer composites, namely, stainless steel mesh/geopolymer and stainless steel mesh/Crp/geopolymer, were designed and prepared, in which the layers of stainless steel mesh were 4, 7 and 10, respectively, and particle size of chromium powder (Grp) were 74, 38 and 13 μm, respectively. The Grp content was 40 wt% of metakaolin used to fabricate the resulting geopolymer composites. Phase composition, microstructure, mechanical properties and fracture behavior of the resulting composites were studied. The results suggested the incorporation of stainless steel mesh could significantly improve the mechanical properties of the composites. The flexural strength, elasticity modulus and work of fracture reached the maximum values, 97 MPa, 11 GPa and 4.2 kJ/m2, respectively, for the composite with seven-layers of stainless steel mesh. The presence of Grp could further enhance the mechanical properties of geopolymer composites, especially for the work of fracture, and the mechanical properties gradually improved with the decreasing of particle size of Grp. The reason for the performance improvement after the introduction of Grp was because that the presence of Grp can effectively reduce the debonding between matrix and stainless steel mesh. All composites showed typical pseudo-plastic behavior that offers potential to prevent catastrophic failure of the geopolymer matrix.