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Ferro Frit 3124

Leadless high calcium borosilicate frit

Alternate Names: F3124

Oxide Weight279.65
Formula Weight279.65
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 7.94
MLRG - Melting Range (C) 1600-1750F

This is a USA pottery frit. Ferro now calls it Frit 3124-2.

This borosilicate frit is high in calcium. It melts are very low temperatures and among the most useful of all common frits because of its glaze-like balanced chemistry. This frit has a chemistry somewhat similar to 3134 (the latter adds CaO, Na2O and B2O3 at the expense of all the Al2O3 and some SiO2.

Its stated intention is a calcium boron source for partially fritted glazes for wall tile and pottery, also in lead bisilicate dinnerware glazes in the cone 3-5 range. However, within pottery circles, like frit 3195 this frit is almost a complete glaze at low temperatures (requiring only a 10-20% addition of kaolin to suspend it). It has a medium thermal expansion and fits most bodies. However if glazes shiver some of this can be traded for Frit 3110. If they craze some can be substituted for Frit 3249. Frit 3124 is often added to glazes to make them melt lower, this works well because it is quite balanced already as a glaze, the net effect of adding it is to increase the boron content without overly disrupting the balance of other oxides.

Since the chemistry is high in CaO, it will affect browns and iron oxide colors.


Do you know the purpose of these frits?

Know the difference between Frit 3134, 3124, 3110, 3249 and 3195? These are 10 gram frit balls fired at 1700F. Each contains boron (B2O3), that is the magic of why they melt this low (Gerstley Borate is a raw source of boron, but it has a very high LOI, gels glazes and is inconsistent). Frit 3124 and 3195 are base glazes, just add 15% kaolin and go. Frit 3110 raises thermal expansion (substitute some of it in if the glaze shivers). Frit 3249 lowers expansion (sub it in if the glaze crazes). Frit 3134? It is similar to 3124 but without any Al2O3, it is useful where you need more clay in the glaze (the clay can source the Al2O3 instead). It is no accident that these five boron glazes are the principle ones used in North America, they complement each other well.

LOI it not important? Think again!

This chart compares the gassing behavior of 6 materials (5 of which are very common in ceramic glazes) as they are fired from 500-1700F. It is a reminder that some late gassers overlap early melters. The LOI (loss on ignition) of these materials can affect your glazes (e.g. bubbles, blisters, pinholes, crawling).

These two frits have one difference in the chemistry. What?

These two boron frits (Ferro 3124 left, 3134 right) have almost the same chemistry. But there is one difference: The one on the right has no Al2O3, the one on the left has 10%. Alumina plays an important role (as an oxide that builds the glass) in stiffening the melt, giving it body and lowering its thermal expansion, you can see that in the way these flow when melting at 1800F. The frit on the right is invaluable where the glaze needs clay to suspend it (because the clay can supply the Al2O3). The frit on the left is better when the glaze already has plenty of clay, so it supplies the Al2O3. Of course, you need to be able to do the chemistry to figure out how to substitute these for each other because it involves changing the silica and kaolin amounts in the recipe also.

Melting range is mainly about boron content

Fired at 1850. Notice that Frit 3195 is melting earlier. By 1950F, they appear much more similar. Melting earlier can be a disadvantage, it means that gases still escaping as materials in the body and glaze decompose get trapped in the glass matrix. But if the glaze melts later, these have more time to burn away. Glazes that have a lower B2O3 content will melt later, frit 3195 has 23% while Frit 3124 only has 14%).

Even highly fritted glazes have to liberate some carbon

Five most common North American Ferro Frits fired at 1850F on alumina tiles (each started as a 10 gram ball and flattened during the firing). At this temperature, the differences in the degree of melting are more evident that at 1950F. The degree of melting corresponds mainly to the percentage of B2O3 present. However Frit 3134 is the runaway leader because it contains no Al2O3 to stabilize the melt. Frit 3110 is an exception, it has low boron but very high sodium.

Out Bound Links

In Bound Links

By Tony Hansen

XML for Import into INSIGHT

<?xml version="1.0" encoding="UTF-8"?> <material name="Ferro Frit 3124" descrip="Leadless high calcium borosilicate frit" searchkey="F3124" loi="0.00" casnumber="65997-18-4"> <oxides> <oxide symbol="CaO" name="Calcium Oxide, Calcia" status="U" percent="14.280" tolerance=""/> <oxide symbol="K2O" name="Potassium Oxide" status="" percent="0.680" tolerance=""/> <oxide symbol="Na2O" name="Sodium Oxide, Soda" status="U" percent="6.400" tolerance=""/> <oxide symbol="Al2O3" name="Aluminum Oxide, Alumina" status="" percent="10.010" tolerance=""/> <oxide symbol="B2O3" name="Boric Oxide" status="" percent="13.740" tolerance=""/> <oxide symbol="SiO2" name="Silicon Dioxide, Silica" status="" percent="54.940" tolerance=""/> </oxides> </material>

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