Cement Extenders Mechanisms & Chemistry
As mentioned in Cementing Additives article, cement extenders are used to reduce cement slurry density & increase slurry yield ( Check also: oil well cement properties). The most common cement extenders chemicals are:

- Clays
- Sodium silicates
- Pozzolans
- Lightweight particles

Cement ExtendersClays

Clay minerals are hydrous aluminum silicates of the phyllosilicate group (Hurlbut, 1971), in which the silica tetrahedra are arranged in sheets.
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