in a foundry, why does the molten metal not melt the vat in which it’s being heated?

Question

I mean, obviously the vat must be made of a metal with a higher melting point. But then how did they cast the metal to make that vat?

In: Chemistry

Answer 1

some materials can actually wind up with a higher melting point than what you started with once the material has hardened and cooled due to how the atoms rearrange and bond during the process. Ceramics are one of these material types, and much of our high end blast furnaces and molds and such are made from ceramics.

As a fun fact, this is also why some igneous rocks, once they have cooled and crystallized, actually have a higher melting point than the lava/magma they originally came from.