How would the inclusion of large amounts of slag affect the chemical analysis of molten metal in a furnace?

Question

If a furnace had previously been melting AISI304, then switched over to AISI316 and there were large deposits of 304 slag in the furnace; in what way would this affect the 316 about to be charged and if at all, why?

I understand fully what slag is and why it's there. What i'm asking is what effect would large amounts of residual 304 or 301 slag have on further melts, in this case the following melt is 316 stainless steel? Would there be any dilution, for example, of the Ni and Mo units? Tom B, thanks but 'obviously' your answer's incorrect.

Thanks Ice Cold, no i'm a supplier of raw product and coolant. I'm just looking for a definitive answer to a quation from a colleague.

Tom B, thanks also, but I can find no data on the Y443g calc?

Answer 1

well obviously the AISI304 would become contaiminated and skew all resulting analysis.
forget that slag, get something that burns cleaner, hotter, smoother.
try new formula Y443g. it works everytime.

Answer 2

Slags are the by-product of smelting ore to purify metals. They can be considered to be a mixture of metal oxides however they can contain metal sulphides and metal atoms in the elemental form. Slags are generally used as a waste removal mechanism in metal smelting, however they can also serve other purposes such as assisting in smelt temperature control and to minimize re-oxidation of the final bullion product before casting.

In nature, the ores of metals such as iron, copper, lead, aluminium, and other metals are found in impure states, often oxidized and mixed in with silicates of other metals.

During smelting, when the ore is exposed to high temperatures, these impurities are separated from the molten metal and can be removed. The collection of compounds that is removed is the slag.

Different smelting processes produce different slags. In general they can be classifed as ferrous or non-ferrous. The smelting of copper and lead in non-ferrous smelting, for instance, is designed to remove the iron and silica that often occurs with those ores and separates it as an iron silicate based slag. Slag from steel mills in ferrous smelting on the other hand is designed to minimise iron loss and so mainly contains calcium, magnesium, and aluminium.

None at all, the inclusion of slag from the 304 would just settle leaving 316 as it is.

Do you manufacture stailnless steel for fitings or plumbling?

Answer 3

Slag is impure, with a lot of carbon in it, and whatever metals you were working with last. It also tends to melt at a lower temperature. So when heat a new sample part of the slag melts and impurities get into your test sample. So yes, you have to clean out the furnace!

Answer 4

Ok here is my answer to your question lol.
Slag is as you know a product of trash that is in molten steel and iron and others like lead and such.
It does not mix with the original metal that it was in to start with and that is why it floats on top.
As long as it is on top you have no problem with it just clean it off .
Only if and when it stops floating and immerses with molten metal would give a problem at all.