G2926B Reduced COE (Li2O)
Recipe
Notes
Remember, the first thing to try to reduce the thermal expansion of G2926B is using 325 mesh silica (or ball milling the slurry). That will help more silica in the recipe to actually go into the melt, that means that the physical thermal expansion will be as low as the calculated one suggests it should be. Second, try G2926S. If that is not enough, then try this recipe. This is the best of a series of tests to lower the thermal expansion of G2926B. Separate trials of substituting ZnO, SrO, Li2O for KNaO were tried (in each the brilliant surface was being marred by an orange peel like surface). This version is a hybrid, diversifying fluxes by adding Li2O and SrO. It sources SrO from Frit 524 and Li2O from Spodumene. The calculated expansion of this is dramatically lower, 5.6 vs. 6.4. This is low enough that shivering could occur on some bodies (opening the opportunity to line blend this with the original G2926B to find a compromise). There is an issue: Spodumene introduces bubbles into the slurry in the bucket (washing it before use could solve this). Color response might also be different.
Description
A very low thermal expansion version of the G2926B base recipe. Use this if the B versions crazes on your clay body.