What does 'solidification ends' refer to in metallurgy?

In metallurgy, 'solidification ends' indicates the temperature at which the entire metal has completely transitioned from a liquid to a solid state. This is a crucial point in the casting and cooling processes of metals, as it marks the completion of crystallization where no liquid phase remains. Understanding this concept is essential when evaluating the mechanical properties of a metal since properties can significantly change depending on the temperature and state of the material during cooling.

The other options describe different phases of the cooling process but do not accurately define the conclusion of solidification. For instance, the point when the metal begins to cool is relevant to the initial stage of solidification but not indicative of its completion. The stage where the metal is still partially liquid refers to an intermediate phase during solidification but does not represent the endpoint. Likewise, the time when solidification is about to begin pertains to the onset of the transition rather than its conclusion. Thus, the definition of 'solidification ends' is specifically tied to when the last liquid metal has solidified.