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glaze viscosity

updated wed 4 jul 12


ivor and olive lewis on tue 3 jul 12

A couple of weeks ago Robert Harris asked about Line blends and then posed
this secondary question....potential change for each ion ?>
My response was "This question can be answered, making one or two
assumptions along the way, by calculating the ionic charge per unit area fo=
each of the ions you are investigating."
Below is a ranked table of viscosity values based on Ionic radius and Ion
Boron seems have be anomalous to me but Boric Oxide it can be regarded as a
glass maker not a flux.. In the melt Silicon Dioxide are immiscible.

Ivor Lewis,
South Australia

Relationship between Ionic Charge and Ionic Surface Area and the Influence
of these Properties on Glaze Viscosity

Element Ion Charge + Charge =CE=94P /sq pm

Boric ion 3
8.29 e -4 High viscosity

Aluminium ion 3
7.85 e -5

Magnesium ion 2
4.73 e -5

Zinc ion 2
4.42 e -5

Lithium ion 1
2.29 e -5

Calcium ion 2
1.59 e -5

Strontium ion 2
1.18 e -5

Barium ion 2
0.86 e -5

Sodium ion 1
0.76 e -5

Potassium ion 1
0.43 e -5 Low viscosity

Data from G.W.C Kaye and T. H. Laby. =E2=80=9CTables of Chemical and Physi=
Constants=E2=80=9D. 14 th Edition,. Longmans. 1982. ISBN 0-582-46326-2