Abstract:
A construction brick made from clay soil and iron slag with variable temperature has been
synthesized. In the process iron slag was collected from steely RMI Bishoftu Ethiopia and clay
soil was taken from Jimma town Frustalle area. The samples was then grinded grounded properly
and sieved to have a fine sample. The samples clay was mixed with a proportion containing; no
slag, 10% slag, 20% slag and 30% slag and water to attain a plastic property and the brick was
synthesized. The synthesized brick is then fired at a temperature of 9000C. 10000C and 11000C
and samples were arranged for characterization. The characterization was made in to three parts;
the mineralogical and morphological property, the physical property and the compression
strength. The mineralogical characterization result shows the clay composed of quartz as a main
content while feldspar and other are the main content at the same time the content of quartz in
the clay brick decreases with increasing in temperature. The mineralogical characterization result
of iron slag also shows the main component of hematite while Ca2SiO4 and CaAl2O4 are the
other component. The increase in firing temperature cause in the decomposition of Ca2SiO4 and
CaAl2O4 and favor the formation of quartz, crystobollite and kaolinite, this indicated that the
samples have good mechanical and physico-sintering properties. Finally the physical and
mechanical characterization result indicates, the addition of iron slag improves the property of
the brick. But the result outcome indicates that the weight loss on ignition violet the expected
result and the percentage of firing shrinkage at 30% slag addition above 10000C did not change.
