Microstructural Investigation on the role of modifiers in the stabilization of different polymorphs of Silicate phases in OPC Clinker

OPC clinker samples were prepared with selected modifiers that have been reported to

have significant effect on the formation of clinker phases. The role of these additives in

the development and modification of the clinker phases has been investigated using

optical microscope, SEM-EDS, XRD techniques. Chemical separation techniques have

been employed to understand the partitioning of the elements such as boron, manganese

and chromium in presence of potassium in the silicate and non silicate fraction of the

clinkers. The paper also evaluates the effect of these element on the microstructure in

terms of phases assemblages, crystal size and morphology and polymorphism of silicate

phases. The study indicates the effectiveness of the elements on alite formation can be

graded in the order Mn2O3 > Cr2O3 > K2O >> B2O3 whereas boron addition

substantially stabilizes the belite formation.