When exposed to very high temperatures, metals like iron can be turned into fluids that flow and can be poured into molds. What happens within the iron to allow it to flow?

When metals like iron are exposed to very high temperatures, they undergo a phase transition from a solid to a liquid state through a process called melting. At high temperatures, the thermal energy provided to the metal overcomes the forces holding the metal atoms or ions in a rigid, ordered structure.

In the case of iron, which is typically solid at room temperature, heating it to a sufficiently high temperature causes the kinetic energy of its atoms to increase. This increased kinetic energy disrupts the ordered arrangement of the atoms in the solid lattice structure. The thermal energy supplied breaks the bonds holding the atoms together, and as a result, the metal transitions from a solid to a liquid.

In the liquid state, the metal atoms or ions are free to move past each other, allowing the metal to flow and take the shape of its container. This molten metal can then be poured into molds to create various shapes and forms upon cooling and solidification. The ability of metals to undergo this phase transition from solid to liquid and back makes them versatile materials for various manufacturing processes.