Composition rules
The composition of the metal compound is very complicated, there are still many regularities, and two types have been summarized: one is equivalent to metal and non-metallic compound Compound price, such as: Mg2SN and Mg2PB, can be "family prices" in cycle, that is, MG is divalent elements, SN, PB is tetravalent elements. Another category is the so-called electron compound, which is determined to be a ratio of the number of electrons and atomic numbers of two metals, but the electronic compound constitutes an unusual number of counts of "electron number", and there is also a controversy. The law is: "Co, Ni, Ru, RH, PD, OS, IR and PT" of periodical line VIII element Fe, CO, Ni, Ru, Rh, Pd, OS, IR and PT "are zero, IB Cu, Ag, Au is 1, IIB Zn, CD, Hg and IIA family BE, Mg is 2, IIIA, II, Ga is 3, IVA family Si, GE, SN, PB is 4, and the like, and the ratio of the number of electrons and atoms has three basic types: 3: 2, 21: 13 and 7: 4, thereby understanding, such as CuZn, Ag3Al, Cu9Al4, Cu3Sn, and the like. The above three types of electronic compounds each have a specific structure, which becomes β, γ, and ε phase, respectively. For example, Cu5Zn8 is a 21: 13 electronic compound, which is a large cubic cell, containing 52 atoms, referred to as γ-brass-shaped structures, and many modes of total chemical formula 13 have this structure. Such as Fe5Zn21, Cu31SN8, etc. The γ and ε phase structures are slight.
Application
Metallic compound alloy is often a large difference in the nature of the metal constituting it. With the development of new technologies, new processes, a variety of new functional materials and structural materials have now been developed, and the most typical metal functional materials are amorphous metal, shape memory alloy, vibration-vibration-vibration, superconducting material, hydrogen Alloy, ultrafine powder, etc .; new structural materials have superplastic alloys, ultra-high temperature alloys, etc. These metallic materials are excellent in performance, widely used, and have broad application prospects.
