Which term describes an alloy where some metals only partially dissolve in each other?

The term that describes an alloy where some metals only partially dissolve in each other is indeed "Partial solubility alloy." This term indicates that in such alloys, certain metals can mix to some extent, creating a solid solution, but not to the point of complete solubility. Partial solubility often leads to the formation of distinct phases in the microstructure of the alloy, which can significantly affect its mechanical properties.

In contrast, a fully soluble alloy would consist of two or more metals that are completely soluble in one another at the atomic level, resulting in a uniform composition. Eutectic alloys refer to specific types of alloys that solidify at a particular composition and temperature, resulting in a mixture of phases that have lower melting points. Homogeneous alloys imply a completely uniform and consistent composition throughout the material, which is not the case in partial solubility alloys where different phases or constituents can be present.