Solvus

A solvus is a temperature-dependent boundary within a material's phase diagram that separates regions where certain elements or compounds are mixed evenly (solid solution) from areas where they tend to separate into different phases or particles. Think of it like a "mixing line": below this line, parts of the material prefer to stay separate, forming distinct regions, while above it, they are more uniformly blended. This concept is important in materials science because it helps predict how an alloy or mineral will behave when heated or cooled, affecting its strength, durability, and other properties.