Relationship between the types of binary alloy phase diagrams of Ⅷ and IB group elements and the Mendeleev numbers

The relationship between the types of binary alloy phase diagrams of VIII and IB group elements and the Mendeleev numbers was discussed for the first time using the VIII and IB group elements as solvent metals (A) and the other elements as solute metals (B), basesd on their alloy phase diagram types. The Mendeleev numbers of the solvent metals and the solute metals were expressed as MA and MB, respectively. A two-dimension map of MA/MB was drawn. It is indi-cated that there is an oblique line in the map, which divides the binary alloy phase diagram types of solvent metals intotwo symmetry parts, the phase diagram types of the other elements with solvent metals located at the above or down ofthe line respectively, while on the line, ΔM= 0. The phase diagrams between the solvent metals basically are simple systems, mainly belong to the types of continues solid solution and the peritectic (about 40% for each type). The solvent metals can be divided into three groups: Co, lr, Rh, Ni, Pt, and Pd as the first group; Ag, Au, and Cu as the second group;and Fe, Os, and Ru as the third group. The characteristics of the phase diagrams formed between the elements in each group were discussed. About 80% phase diagrams belong to complex systems and less than 20% belong to the simple systems. The regular variation of the chemical scale, the metallic radii of the atoms, the number of valence electrons, and the first ionization energy with the Mendeleev numbers and the crystal structure were introduced as well.