You may remember school chemistry lessons conducting experiments with magnesium to ignite it and set off a bright, white chemical reaction, but did you know that we also use magnesium parts in STIHL tools?
STIHL has over 60 years of experience working with magnesium alloys at our dedicated casting plant in Prum, Germany and it has been a core component of our machinery for many years. The most notable use of magnesium in recent years has been our development of a new lightweight piston on the MS 400 C-M chainsaw. This component gives it the highest working speed in the 60cm3 class, a formidable 14,000rpm, whilst also having an excellent weight to power ratio of 1.5 kg per kilowatt.
The state-of-the-art magnesium diecasting plant where our components are manufactured from raw magnesium through to the finished product was set up in 1971 and is currently one of the largest magnesium diecasting plants in Europe with over 700 employees. For more than 60 years, magnesium has been fabricated by STIHL for use in our machinery, as well as for other companies, such as those in the automotive industry.
STIHL recently won a top award for the magnesium piston used in the MS 400 C-M chainsaw, the world’s first chainsaw with a magnesium piston! The Award of Excellence 2020 was given by the International Magnesium Association (IMA) for the component and production process which was specifically developed for the MS 400 C-M’s piston, winning the Commercial Cast Product or Process category.
It’s not just smaller components like the piston in the MS 400 C-M that magnesium is used for though. It’s used as the crank case on the engine for many high performance professional tools, including forestry chainsaws such as the MS 261 C-M. It’s also used for pro chainsaw sprocket covers, the cutting disc guard on our TS 410 and other construction cut-off machines. And it’s used for the pole pruner heads and long-reach hedge trimmer cutter bars to help reduce weight and strain on the users, whilst remaining strong.
Magnesium has been used for years across a diverse range of products due to its mechanical properties as a material. It is lightweight, strong and stable, which is exactly what you need for power tools. It’s also optimal for casting, easy to machine and can be recycled without limit too, so at the end of a machine’s life, it can be turned back into a new machine.
The die-casting process with magnesium allows for excellent dimensional accuracy which is very important when building an engine within high tolerances, and thin walls can be used where required to reduce weight. It also has good attenuation properties to help with vibration too.
If you think back to those magnesium experiments in your chemistry lessons, you may be wondering why your STIHL chainsaw doesn’t have the same reaction?! Well, that’s because we use a magnesium alloy, known as EN-MB MgAl9Zn1(A) (AZ 91). It’s a catchy name, we know! But this is actually the most common diecasting alloy due to its casting properties and mechanical strength. It is used in everything from automotive parts to sports equipment and household appliances.
You can find out more about our magnesium diecasting plant and even watch a virtual factory visit at www.magnesium.stihl.com/.