The effect of Si content (in the range of 0.01 to 1.91 wt.%) on scale formation on electric steels in air
at the temperature ranging from 850 to 1200 oC was investigated. The effect of applied tensile strain on
oxidation behavior was also explored. A thermo-mechanical simulator (Gleeble machine) was employed
to conduct the oxidation tests at different strain rates. The experimental results showed that at
temperature below 1100 oC the oxidation rate decreased with increasing Si content in the steel. The
formation of an inner scale, mainly consisting of silica, was responsible for the improved oxidation
resistance. However, a substantial increase in oxidation rate due to the formation of molten eutectic
fayalite (Fe2SiO4) was observed when the temperature was raised to 1200 oC. Under straining
conditions and at very short oxidation time, the inner scale structure was slightly modified though the
scale thickness remained almost unchanged for the steel containing 1.91 wt% Si.