The density of magnesium is very low, so alloys that are made mainly from it are very light. Recently, they have become popular for the casings of mobile phones. Thanks to their low melting point, they are very easy to recycle. They are becoming increasingly popular in cars due to the fuel efficiency improvements that come from lighter weight. The VW Beetle contains a lot of magnesium alloy parts.
Properties of AM60A and AM60B Magnesium alloys
Processing and Forming
They are among the most easily machinable metals, but they are not weldable.
They are easily corroded by chlorides and sulfates so they are often anodized for their protection.
They are very easily castable.
They are often annealed, strain hardened, solution heat treated, artificially aged, cold worked, or some combination thereof.
Web Reference
http://members.tripod.com/Mg/asm_prop.htm