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on strength loss from crazing

updated tue 31 dec 96

 

Janet H Walker on tue 3 dec 96

Strength loss from crazing is a phenomenon described in the
various ceramic science texts I've been grappling with. I also
had a real life demo of the phenomenon when two pieces of
similar construction fell from a shelf. One bounced and the
other had a piece crack off. Guess which was which? Science
isn't "just theory" (as someone assured me once); it provides
a way of understanding observations!

So it was interesting to observe the broken edge of the piece
with the crackled glaze -- very uneven along the glaze side
and more even on the inner side (where there was less crackle).

Just thought I'd add this to back Tony up. Although, where I
come from, tensile strength measurements beat out anecdotes
every day, that isn't true for everyone.

Regards,
Jan Walker
Cambridge MA USA