Magnesium is ready for the future
Just like aluminium, magnesium is considered to be a major design material of the 21st century, as it is especially light, yet also extremely robust and has excellent casting properties. Magnesium products are highly suited for mechanical processing and are recyclable. ALUMINIUM 2018 puts a special focus on this material, giving it a themed pavilion – the Magnesium Area in Hall 10, where developers and designers will find new ideas in lightweight design.
There is currently an unmistakable trend towards magnesium alloys in the industry. This metal weighs about one third less than aluminium, and designers have therefore been using it for many years now. Magnesium has had a long tradition in the automotive industry. In the 1930s, the VW Beetle contained more than 30 kg, although it was subsequently forgotten for over 50 years.
Thanks to intensive research into lightweight design in the 1990s, magnesium then rose to become one of the most sought-after materials. Today, lightweight components made from magnesium alloys can be found in a large number of vehicles and aircraft. Steering wheels, seat backs and casing components are now made from this multitalented material. Moreover, innovative, lightweight magnesium alloys can be found in many electrical appliances and machines.
This is hardly surprising, as such parts are not only lightweight, but they also allow competitive, low-cost manufacturing methods. Specialist foundries can now produce parts with thin walls with an accuracy which is hard to beat. But there are also further benefits. Short casting cycles and a long die service life are well-known properties of magnesium diecastings. Further advantages in application include their excellent machinability, good sound absorption and electromagnetic shielding properties. High purity and advanced corrosion-proofing techniques are now also making it possible to use magnesium diecasting alloys in corrosive environments without any problems.
The most important magnesium die casting alloys and some typical product segments:
- EN-MB MgAl9Zn (AZ 91)
Outstanding casting properties and high level of stability. Typical applications: automotive engineering, parts for computers and mobile phones, lids and cases, sports equipment and components, e.g. for power saws, hand tools and household appliances.
- EN-MB MgAl5Mn (AM 50) und EN-MB MgAl6Mn (AM 60)
Especially high elongation and energy absorption with high mechanical strength. Typical applications: seat frames, steering wheels, dashboard supports and fan wheels.
- EN-MB MgAl2Mn (AM 20)
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This alloy is characterised by a high level of elongation, combined with excellent impact resistance. This makes it particularly suitable for safety components.
Because of its low density, magnesium has excellent potential in lightweight design with a range of different alloys. Researchers are working intensively on processes that also allow the cost-effective and industrial-scale production of components and blanks made from wrought alloys. This is an area where experts are seeing considerable additional potential and where they perceive the future of lightweight design.
This is accompanied by an increased focus on the development of new alloys and enhanced manufacturing and processing methods. However, such new applications can only be developed if the relevant processes are sufficiently productive, covering all stages of the value chain. Processes and process chains are currently being tested so that they can become available for serial production. They allow, for instance, deep and stretch forming, pipe bending, roll forming, hydroforming, extrusion and laser welding, all of which make use of magnesium's special properties.
One highly unusual application for such a high-tech material is the use of magnesium in today’s biomaterial research. Scientists are currently investigating magnesium implants that dissolve in the body after a specified time, making it unnecessary to conduct a second operation to remove the implants.