The good effect has been gained on the hypereutectic Al Si alloys treated with some double refining and modifying agents such as P, S, RE, Sr, Na, C, etc.

Double metal rolling fin tubes are widely used in refining, chemical, power plant and many other industries because they have good heat transfer, mechanical, anti-corrosion performance.

This paper recommended a kind of agent of fusion and it's adding technolgy, which had double actions of depressing magnesium content and refining in molten aluminium alloy.