Sample preparation technique on interfacial transition zone of steel fiber reinforced mortar

A grinding and polishing procedure for steel fiber-reinforced mortar with a total time of 15 minutes and an average final surface roughness less than 1 μm is presented in this paper. This technique is performed on 3 different types of steel fiber-reinforced mortars, which are at w/b 0.3, with 0 and 10% silica fume and at w/b 0.5 with 0% silica fume. The samples prepared were then used for quantifying the interfacial properties at the region close to steel fiber using the backscattered electron image analysis and the nanoindentation. It reveals that the interfacial transition zone of steel fiber that has a diameter of 0.16 mm is around 30 μm. Steel fiber-reinforced mortars at w/b 0.3 with 0 and 10% silica fume have similar area % of porosity in the interfacial transition zone. However, according to a hardness profile, steel fiber-reinforced mortars at w/b 0.3 with 0% silica fume have better bonding in the interfacial transition zone compared to that with 10% silica fume.