Effect of oxide additives on densification of terracotta
Source abstract
Abstract
In this study, the effect of the addition of a few oxides (TiO 2, Cr 2O 3, Fe 2O 3 CaCO 3, and MnO 2) on the sintering behaviour and sintered properties of a raw clay are reported. Static sintering study revealed that, except CaCO 3, all remaining compositions showed similar values of firing shrinkage, which is greater than the control batch. Both TiO 2 and MnO 2 addition leads to lower open porosity at 1000 °C. Dynamic sintering studies at a heating rate of 5 °C.min −1 reveal that the onset of vitrification is in the following order: MnO 2 > CaCO 3 > control, TiO 2 > Cr 2O 3, Fe 2O 3 and few oxides (TiO 2, Cr 2O 3 and Fe 2O 3 ) improve the firing range and sintering compared to control composition. The terracotta body`s flexural strength was influenced by porosity and chemistry. An overall negative linear correlation between flexural strength and open porosity was evident. The beneficial role of Cr 2O 3 and TiO 2 over other oxides can also be clearly discerned. The lightness value (L*) of the terracotta body did increase only with TiO 2 addition. A clear trend of change in chromacity components (a* and b*) was affected by oxide addition and firing temperature. The incorporation of Fe 2O 3 improved the characteristic red colour of the terracotta, along with other positive effects on the sintering of the terracotta body.
Source: expertdata · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Recycling and utilization of industrial and municipal waste in materials production · Clay minerals and soil interactions · Concrete and Cement Materials Research
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
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