|Monthly Tech-Tip |
These grow in the porcelain matrix during firing and are a big reason why vitrified porcelain is so strong (the fired porcelain matrix is not just a bunch of silica particles glued together with feldspar glass, it has a complex structure, mullite is a key part of that). Mullite crystals are converted from kaolin particles and are long, producing a fibrous mesh.
Ceramics, by their brittle nature, have high compressive strength. But in functional ceramics we are more concerned about the tensile strength as this relates better to serviceability.