It is a single phase structure.

The structure has two phases, Compound A solid solution and chemical compound. The microstructure consists of a solid solution of component A and an eutectic mechanical mixture of the solid solution and the chemical compound.

It is two phase structure of A and B solid solutions. The microstructure consists of a solid solution of component A and an eutectoid mechanical mixture of A+B solid solutions.

It is two phase structure of A and B solid solutions. The microstructure consists of a solid solution of component A and an eutectic mechanical mixture of A+B solid solutions.