Corrosion of magnesium alloy

Poor heat resistance is one of the main reasons that hinder the wide application of magnesium alloy. When the temperature increases, its strength and creep resistance function greatly decrease, making it difficult to be used as a key parts (such as the idea parts) material in automobile and other industries, with the development of semi-solid casting technology, Thixotropic casting in prefabricated material uniformity, and cost control of induction heating and material consumption, reliability and repeatability of the forming process, waste recycling, etc, more and more obvious, the economic benefit is hard to do people, thus developing the rheological casting again brought to the attention of the people, Japanese Hitachi and UBE developed new rheological casting technology and equipment.

Mg -- Al -- Si(AS) alloy is a die casting magnesium alloy developed by Volkswagen ag. In addition, in order to improve the high temperature creep resistance of magnesium alloys, magnesium alloys with rare earth elements as the main component were produced. Among them, only 2000T is used for santana car gearbox housing, the rest are used for general purposes such as alloy preparation. The pressure chamber is directly immersed in the magnesium liquid in the crucible and is in the state of being heated for a long time. The injection parts are installed above the crucible.

Rare earth is an important element used to improve the heat resistance of magnesium alloys.

The corrosion resistance of magnesium alloys can be solved from two aspects:

1) Strictly limit the contents of impurities such as Pe, Cu and Ni in magnesium alloys. In 2000, the national output was about 200000T, more than 80% of which were exported at low prices as primary raw materials, and the domestic consumption was about 20000T. In this paper, the development of cast magnesium alloy is introduced. According to the research of Japanese scholars, adding a certain amount of calcium can obviously improve the ignition temperature of magnesium alloy, but there is a high amount of calcium, and seriously deteriorate the mechanical properties of magnesium alloy.

(3) In the third stage, silver is added to the magnesium alloy. After silver alloying, the aging strengthening effect can be enhanced, and the high temperature strength and creep resistance of the magnesium alloy can be greatly improved, but the corrosion resistance of the alloy will be reduced.

To a wider range of applications.