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Ferro Frit 3134

Leadless and zero alumina high calcia borosilicate frit

Alternate Names: F3134

Oxide Weight190.69
Formula Weight190.69
Enter the formula and formula weight directly into the Insight MDT dialog (since it records materials as formulas).
Enter the analysis into an Insight recipe and enter the LOI using Override Calculated LOI (in the Calc menu). It will calculate the formula.
COLE - Co-efficient of Linear Expansion 9.60
MLRG - Melting Range (C) 1450F

This is a popular frit and has been used for many years as a general purpose melter across all tempreatures. Equivalents are made by many frit companies. Ferro says that it is "intended for use as a lime and borate source in partially fritted glazes, lead bisilicate glazes and low cost hobby glazes cone 06-10". But from the viewpoint of ceramic chemistry, this frit is a great 'oxide warehouse', it is useful in so many kinds of glazes, we often use it to showcase the value of Frits in formulating and adjusting glazes as (formulas of oxides rather than recipes of materials).

The reason this is billed as useful in partially fritted glazes is because of how valuable it is in supplying B2O3 (raw B2O3 sources have many issues).

Several factors make this frit's chemistry so attractive:

-It has no alumina. That means that Al2O3 can be supplied by clay, giving the glaze better suspension and hardening properties. Conversely, adding Frit 3134 to a recipe (to supply boron for example) does not require reduction of clay content.
-It has high sodium. That means that it's presence enables reducing feldspar content which in turn provides even more opportunity to source Al2O3 from kaolin or clay.
-It has high boron. That gives it a lot of bang-for-buck as a flux, especially in middle temperature.
-It has a very high CaO content. That makes it useful for developing chrome-tin pinks and maroons. CaO-sourcing raw materials do not normally melt at low temperatures but a frit of this chemistry (high soda and boron) does.

The high expansion of this frit is quite useful since it can be used in a frit blend to create low-temperature glazes with adjustable thermal expansion. The high boron means it can tolerate a very high alumina content from other materials, especially clay. For example, 40 Frit 3124, 40 Frit 3134 and 20 Kaolin is expansion-adjustable since the Frit 3134 can be increased at the expense of 3124 if the glaze is shivering and vice versa if it is crazing.

This frit is often used effectively as part of the strategy to substitute for Gerstley Borate in glazes. It is valuable because it contains lots of sodium and calcium while at the same time sourcing the B2O3. This often enables reducing the feldspar content in the glaze, and then replenishing the oxides contributed by both it and the GB with this frit and kaolin (the latter of which acts to suspend and harden the glaze slurry).

Since Frit 3134 contains no Al2O3, it is not a completely stable glass, it can leach in glaze slurries over time and precipitate. It is often possible to reduce its amount in favor of the more balanced Frit 3124 (where the glaze has significant feldspar). However, if you drive the clay content too low to accomodate the Al2O3-containing Frit 3124 (using ceramic chemistry), you may find the extra hassle of poorer application properties and powdering worth enduring some precipitation issues.

Sub: See also: TAM C-14, General 367-A, 4508

Out Bound Links

In Bound Links

Metallic oxides with 50% Ferro frit 3134 in crucibles at cone 6ox. Chrome and rutile have not melted, copper and cobalt are extremely active melters. Cobalt and copper have crystallized during cooling, manganese has formed an iridescent glass.

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Defect free fired surface of alberta slip plus 20% frit 3134 at cone 6 oxidation on a dark and light burning clay body.

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Alberta Slip fired at cone 6 using 20% frit 3134 (left) and 20% frit 3249 (right).

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Crystallization of rutile is completely subdued using Ferro frit 3249 (20% with Alberta Slip) on the right (the left is frit 3134 20%)

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Alberta slip cone 6 base (80:20 with frit 3134) plus 4% rutile

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Frit balls fired at 1700F. Frit 3124 and 3195 are base glazes, Frit 3110 and 3249 modify expansion and 3134 is similar to 3124 but without any Al2O3. Gerstley Borate is a raw source of boron, it has a very high LOI.

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By Tony Hansen

XML for Import into INSIGHT

<?xml version="1.0" encoding="UTF-8"?> <material name="Ferro Frit 3134" descrip="Leadless and zero alumina high calcia borosilicate frit" searchkey="F3134" loi="0.00" casnumber="65997-18-4"> <oxides> <oxide symbol="CaO" name="Calcium Oxide, Calcia" status="U" percent="20.100" tolerance=""/> <oxide symbol="Na2O" name="Sodium Oxide, Soda" status="U" percent="10.300" tolerance=""/> <oxide symbol="B2O3" name="Boric Oxide" status="" percent="23.100" tolerance=""/> <oxide symbol="SiO2" name="Silicon Dioxide, Silica" status="" percent="46.500" tolerance=""/> </oxides> </material>

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