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Each type of alloy has the following connectivity:

(1) most alloy melting point is lower than any of its components is composed of metal melting point;
(2) general hardness is greater than its components in any metal hardness; (exception: potassium sodium alloy liquid, used in the thermal conductive agent) in the reactor
(3) the electrical conductivity of the alloy and the thermal conductivity is lower than any metal components. Using the characteristic of alloy, can produce high resistance and heat resistance of materials. Can also produce a special performance of materials.
(4) from corrosion resistant ability (such as stainless steel), such as iron mixed with 15% chromium and 9% nickel have been a kind of corrosion resistance of stainless steel, suitable for chemical industry.