I know that in order to smelt stuff, you need to heat it until it melts and then pour it into a form. But that oven and that form always need to have a higher melting point, right? So how do we create the oven at the top? How do we create stuff when nothing with a higher melting point exists to make an oven out of it?
Edit: I think I understand now, thank you again to the kind people in the replies who explained it to me 🙂
In: Technology
There are multiple avenues to answer this, but here’s a couple generic answers.
What you pour it into doesn’t have to be a true solid. It could, but doesn’t have to be. You can cast iron into sand, which is readily available and can form rough shapes, and it has the benefit of a higher melting temperature than iron.
You seem, though, to be getting at “If you keep casting things into things that can’t be melted by that liquid thing, and if you keep going up that chain, how do you cast that highest melting temperature thing.”
Melting is a physical change. You heat it up until it changes phase. You can shape that liquid into a form, cool it back into a solid, and you’re good. But there’s more ways to turn a not-solid thing into a solid thing. Chemical changes!
The most common one in this chain of thought is the production of ceramics. You can take clay, which is moldable at room temperature, and bake it at high temps. This forces out the water and the clay undergoes a transformation into a ceramic. This is a simple way of making molds that can withstand high temperatures without having to first mold the material the mold is made of (and further have a mold that can withstand *that* temperature, and so on).
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