More Magnesium in Japanese Auto-Parts Makers’ Mix

TOKYO – After a decade of flat or declining demand, magnesium may be getting a second look by Japanese auto-parts manufacturers.

The lightweight metal, which is two-thirds as dense as aluminum, is used to make cylinder-head covers, oil pans, steering-wheel armatures, key locks and seat frames, but only on limited models.

Among its more recent applications: the power-control-unit case for the Honda Insight, tweeters for the automaker's RLX Sport Hybrid, valve covers for the Toyota Venza and radiator cores for the Nissan Patrol.

Hisashi Ohara, Japan Magnesium Assn. executive vice president, predicts demand will grow 3% to 4% over the next five years thanks to a new alloy mix incorporating calcium, making it possible to die-cast magnesium components on the same line as aluminum parts.

The new alloy is substantially less flammable.

Japanese suppliers of magnesium components include Aisin Seiki, Ahresty, AutoLiv, Honda Lock, Keihin and Toyoda Gosei. Ohara indicates hybrids and electric vehicles might be a future market for magnesium parts, in particular power-control units, but says there now are no specific plans to target the segment.

The Japanese market for magnesium auto parts peaked at an estimated 9,640 tons (8,743 t) in 2007, the year before the global recession. Demand plunged to 5,493 tons (4,982 t) in 2009 and has fluctuated since then; volume last year was 6,000 tons (5,442 t), almost all of it for die castings and the rest for injection moldings.

Including overseas production, Ohara estimates the Japanese auto industry’s total usage at 12,000 tons (10,880 t) out of global demand of 200,000 tons (181,400 t), with the major markets being the U.S., Germany and China.

A forecast by ResearchInChina projects global demand will exceed 300,000 tons (272,100 t) in 2015.

Contributing to the Japanese decline are cost-cutting activities by the nation's automakers following the recession along with a pronounced shift to smaller cars.

High-tensile steel is hands-down the preferred material by the Japanese auto industry for lightweighting as it is substantially cheaper than either aluminum or magnesium. And Ohara estimates aluminum is 15% to 20% cheaper than magnesium.

Smaller vehicles, specifically minicars powered by 0.6L engines, now account for 40% of domestic demand and 22% of production.

A third factor, according to the executive, is fear of becoming dependent on China, currently the world's primary source of magnesium, prompting parts-makers’ interest in aluminum or high-tensile steel for lightweighting.

Ohara reports China controls 90% of global magnesium production.

In 2012, Japan imported 30,598 tons (27,752 t) of magnesium from China, or 95% of all shipments into the country.

China on Jan. 1 eliminated export tariffs on nine materials including magnesium to comply with a World Trade Organization ruling on a complaint filed by the U.S., the European Union and other countries that the tariffs violated global trade agreements.