According to the name of the major metal in the alloy, the classification is called a certain alloy, such as copper alloy, which mainly maintains copper performance. Alloy type: (1) mixture alloy (blends), when liquid alloy solidification, the composition of each component of the alloy crystallization of the alloy, such as solder, bismuth and cadmium alloys, etc. (2) Solid melt alloy, when liquid alloys are solidified to form solid solution alloys, such as gold and silver alloys, etc. (3) Metal intermetallic alloys, the alloys of each component form compounds, such as copper, zinc, brass (β-brass, γ-brass and ε-brass). Many of the alloys are superior to pure metals, so they are mostly used in the application materials (see Ferroalloy, Stainless steel). The continuity of alloys: All types of alloys have the following: (1) Most alloy melting point is lower than its components of any kind of metal melting point; (2) hardness is generally greater than the hardness of any metal in its components; (Special case: Sodium potassium alloys are liquid, used in atomic reactors) (3) the conductivity and thermal conductivity of the alloy is lower than any one of the metals. With this characteristic of alloys, high resistance and heat resistance materials can be manufactured. Materials with special properties can also be manufactured. (4) Some corrosion resistance (such as stainless steel), as in the iron mixing 15% chromium and 9% nickel to obtain a corrosion-resistant stainless steel, applicable to the chemical industry.