Forming and working metals
Some understanding of how metals are formed is necessary to their use. The main methods are shaping from molten metal; from hot, solid metal; from cold metal; and from powdered metal.
Casting This is a molten-metal process, often done in sand molds—but it may also be done by die casting (permanent steel or cast-iron dies or molds are used to make castings of zinc, aluminum, or alloys); by continuous casting (pouring into a water-cooled mold and withdrawing the billet of cast metal into a tank of water below the mold); or by centrifugal casting (in which molten metal is poured into a spinning, cylindrical, mold).
Rolling A method used mainly with steel, which can be hot or cold rolled. Hot rolling involves rolling white-hot ...