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: re: crazing! beating a dead horse

updated sat 10 feb 07

 

Ivor and Olive Lewis on fri 9 feb 07


Dear Ron,=20

You say and ask bodies - it is well documented in the white ware industry literature - =
how would you explain moisture expansion in such bodies?>>.

I wouldn't.

But consider that (Cardew) Kaolinite looses Hydroxyl radicles starting =
between 450-550 deg C changing to metakaolin, vitrification commences at =
800 deg C (Hamer) and above 1000 deg C metakolin decomposes to give =
Mullite and free Silica (Hamer).

That seems to cover Whitewares.

So, my question remains. What do you mean by "Hydration". Is it a =
chemical reaction, and if it is, what are the reactants and the =
products, or is it a physical association ?=20

Best regards,

Ivor