14D Chart Thread, page-425

Q: How do 14D store the molten silicon and why doesn't it melt the metal container?

A: Molten metals are nothing new to industry, they are using containment methods that utilise standard industry materials and techniques. There is a limit to how much they can talk about how they do what they do, ... but the following info might be useful for those who'd like to know more.


It depends on the material being melted, and the quantity. When looking at things like bronze or aluminum (950C and 660C respectively) using an iron or steel crucible (just over 1500C melting point) gives a pretty large margin where the crucible won't melt. Of course, what happens when you need to melt and hold iron? A steel alloy crucible is used, lined with a special ceramic that can take the heat and insulate the crucible from the molten metal (that could melt through, if not for the ceramic insulation).
On some higher end ones, there is an extra layer of insulation between the internal ceramic crucible, and the external "support" crucible. Sometimes, the outside crucible is even water cooled to help keep it from melting. Also the reservoir can be made from a special ceramic, the metal is just the outside container to provide support.