When the Society of Automotive Engineers held their annual gathering earlier this year there were over 60 presentations about automotive designing with magnesium. There were dozens of other topics covered, too, of course, but magnesium’s emergence as a viable material for automotive construction was clear. With so much emphasis now placed on fuel savings by analysts, investors, and consumers, the light metal may have finally achieved credibility as a material for automotive design.
Of course, magnesium diecastings are in place already in certain vehicles: the dashboard of the Dodge Viper, engine cradle of the Chevy Corvette, front-end module of the Ford F-150 pickup, and several more applications.
At SAE one presentation detailed DaimlerChrysler’s six-year effort to recreate a production-model sedan body-in-white using magnesium. Diecastings knocked off almost 40% of the weight of the structure, from 981 to 595 lb. They also cut the number of parts from 204 to 44, and they maintained or improved the structure’s strength measurements.
The large, thin-wall magnesium diecastings used in this structure helped to simplify the manufacturing process, too, and projections indicated that producing 250,000 such vehicles per year, with suitable joining and assembly techniques, would have considerable effects in reducing investment costs.
Another magnesium research effort is part of the U.S. Automotive Materials Partnership (involving Chrysler, Ford, GM, and several dozen supplier companies, including some metalcasters.) They have created a magnesium-alloy engine, modeled after Ford’s 2.5-liter aluminum Duratec engine, but reportedly 15-20% lighter.
Magnesium’s advantages are well known: it is lighter than aluminum, some of its alloys can be cast in to thin-wall sections and others have deep-drawing qualities. It also generates less heat during casting than aluminum, so die life is not a particular concern.
There have been obstacles along the way. Metallurgists and diecasters have worked to make molten magnesium easier to handle. And, always, there have been pricing concerns. The International Magnesium Assn. earlier this year revealed that the price ratio of magnesium to aluminum finally had dropped below 1.5:1, which the association regards as parity. Some established magnesium producers are studying an index for their products, to manage price volatility.
But if all this does add up to an automotive breakthrough for magnesium, it’s going to happen without one of the world’s largest producers of the metal. Norsk Hydro is looking to sell its 50,000-metric tons/year magnesium smelter in Bcancour, PQ, but will close it and likely exit the global magnesium market all together even if no buyer is found. The company closed its magnesium smelter in Norway in 2002, and last year ended magnesium casting at that site.
If Hydro does exit, it will join Alcoa, Dow Chemical, and Noranda as ex-producers of magnesium — all of them pushed out of profitability waiting for the moment when magnesium became viable option for large-volume consumers, like the automakers. Easing them out of the market have been low-cost producers in countries where operating costs are less taxing and profitability is less of an obligation.
This is how things are developing in the magnesium sector. There are similar developments in the supply chains for iron ore, steel scrap, stainless steel, copper, and titanium. Demand for critical raw materials is burgeoning in new industrial economies, and the resources for these materials are being consolidated among fewer and fewer suppliers. As the manufacturing economy takes on a more global nature, securing reliable supplies of raw materials may be as critical as establishing a market.