What is the common example of a partial solubility alloy?

A partial solubility alloy is characterized by the fact that the components do not completely dissolve in each other in all proportions, forming distinct phases or microstructures. The lead/tin alloy is a classic example of this type of alloy because lead and tin exhibit partial solubility at certain temperatures. In specific compositions, the two metals form a mixture that results in distinct phases, which are critical in applications like soldering.

Bronze, which is primarily an alloy of copper and tin, can be considered to have more complete solubility at certain ratios, leading to a more uniform microstructure. Steel, primarily composed of iron with small amounts of carbon, typically exhibits complete or nearly complete solubility of carbon in iron at certain temperatures but is not classified as a partial solubility alloy. Likewise, the copper/zinc alloy, or brass, generally has good solubility for varying amounts of zinc, especially in the range common for practical uses, yet it does not consistently create the distinct phases indicative of a partial solubility alloy.

Thus, the lead/tin alloy is the best representation of a partial solubility alloy due to the presence of distinct phases based on the composition, making it suitable for applications like solder, where