Re: Armchair metallurgy
The bubble source is completely different. In concrete the bubbles result from air entrapment, can shake them out before the concrete solidifies. In metal casting, bubbles form at the point of solidification. The molten metal contains dissolved gases that come out of solution when the metal cools and solidifies. Can be reduced by casting in a vacuum or inert gas.
I suspect casting a high-temperature alloy would pose some problems.