ABSTRACT
Table I. Mixture EroEortions (by weight) Mix 1 2 3 4 5 6 7 8 9 10 OPC type I 50 52 90 40 10 20 50 70 100 Slag 15 50 100 90 80 50 30 Fly ash 50 25 Silica fume 3 10 10 water/solid 0.22 0.25 0.22 0.22 0.30 0.22 0.22 0.22 0.22 0.22 KOH* 2 2 2 4 3.6 3.2 2 1.2 *P-14 was used NaOH instead of KOH, and 3% Mighty 150 was use in all mixtures
of x-ray diffraction (XRD). The morphologies of hydrates were observed by TEM. The specimens were crushed in an agate mortar with isopropanol, which is often used as an inert liquid. A drop of the dispersion was then transferred to a carbon-coated TEM grid, and the liquid was allowed to evaporate. The TEM was a Philips EM 420 with acceleration voltage of 120 kV. Bright field images showed the morphology and contrast of the individualgrains. Selected area electron diffraction patterns (SAEDP) from regions of 100 to 200 nm showed if any crystalline or nano-crystalline phases were present. Crystalline phases would form either single crystal spot diffraction pattern or powder diffraction "rings", whereas completely amorphous material would only show a very broad and very weak ring. BY By using reflections from from the SAEDP (reference) it is possible to detect crystalline phases down to 1 nm, which would appear light on the dark field image.
