WHAT IS CEMENT?
MUST READ : MANUFACTURING PROCESS OF CEMENT
INGREDIENTS OF CEMENT
Cement is manufactured from Lime, silica, alumina and iron oxide. Lime is obtained from limestone and oxides of silica, alumina and iron which is found in clay and shale.
Lime is the major and main constituent of cement and which accounts to about 60-65%. Lime is the main ingredient for production of calcium silicates aluminates and responsible for the cementing properties and strength of cement. The proportion of lime content can alter the properties of cement. Less quantity of lime can reduce the strength of cement and higher lime content can make the cement unsound. Lime in correct proportions is responsible for the strength of cement.
SiO2 or silicon dioxide is called silica. Silica is responsible for the formation of dicalcium silicate and tricalcium silicate in reaction with lime . Right proportions of silica plays a major part in inducing cement strength.
Alumina is responsible for lowering the clinkering temperature and controlling the setting time of cement. Alumina imparts quick setting properties in cement and any increase in proportions can weaken the cement.
e) Iron oxide
Iron oxide is responsible for colour of the cement and it acts as a flux in the cement manufacturing process . It acts as a flux in high temperatures and combines with calcium and alumina to form tricalcium alumino ferrite which is the main ingredient behind the hardness of cement.
f) Magnesium oxide
Magnesium oxide is found in minor traces but increase in the quantity can reduce the strength of cement.
g) Sulphur Trioxide
Sulphur trioxide is available in traces but any increase can effect the cement quality.
PROPERTIES OF CEMENT
Also read : PHYSICAL PROPERTIES OF CEMENT
Also read : CHEMICAL PROPERTIES OF CEMENT