Early in the product development process the designer must assess the question of material supplies and pricing, not only for current conditions, but also over the expected production life of the product.
The processes employed to produce, distribute and cast die casting alloys are essentially safe and environmentally compatible. Because of this, the industry is not subject to sudden changes in operating practices and the associated manufacturing interruptions and increased costs arising from government regulations relating to the safety of workers or environmental pollution.
The price of die casting alloys, like other commodities, tends to fluctuate with market conditions. However, die casting alloys are not as sensitive to supply problems as are many materials, because the supply sources for aluminum, magnesium and zinc enjoy stability that is matched by few materials.
Video Images © Norsk Hydro, Graph Data Source: USGS Mineral Commodity Summaries
Aluminum Supply
Aluminum die casting alloys are made from recycled metal. Secondary (recycled) aluminum is more economical to produce than primary because it requires only 5% as much energy to produce a pound. Current projections indicate that the supply of recycled aluminum will be adequate to meet the needs for aluminum die casting into the foreseeable future. Used beverage cans (UBC) comprise a large portion of the aluminum available recyclers. The supply has been enhanced by the widespread recycling of beverage cans.1 Aluminum smelters are widely dispersed across internationally.
Video Images © Norsk Hydro and © Alcoa
References
- Polmear, Ian J. Light Alloys: From Traditional Alloys to Nanocrystals, 4th Ed., Elsevier, Burlington, Massachusetts, 2006.
Magnesium Supply
Magnesium die casting alloys are made from primary and secondary metal, with primary metal accounting for the largest portion. Recycled magnesium, similar to aluminum, requires only a small fraction as much energy to produce as does primary. Therefore, alloys made from recycled metals cost slightly less than alloys made from primary. However, they are lower in purity and should be specified only in applications where lower purity is tolerable.
Magnesium “ore” is considered to be limitless, and it is readily accessible to any nation with magnesium rich mineral deposits, or salt water sources. Currently (2008) the primary magnesium source for alloy production is land based mineral deposits. The secondary source is sea water, which is 0.13% magnesium. Other salt water sources, such as brine wells and salt lakes, offer viable supplies.1 These natural sources ensure that magnesium supplies are readily available.
References
- Polmear, Ian J. Light Alloys: From Traditional Alloys to Nanocrystals, 4th Ed., Elsevier, Burlington, Massachusetts, 2006.
Zinc Supply
Zinc die casting alloys require high metal purity in all applications. Therefore, they are made only from high-purity (99.990%) primary zinc. The mines and smelters that supply the zinc used by North American die casters do not generally operate at full capacity. Zinc is used in a variety of industries, including corrosion protection for steel (galvanizing). The broad use of zinc and the margin in production capacity contribute to a stable supply of the metal for zinc and ZA die casting alloys. Zinc and ZA alloys are produced and distributed by smelters and alloyers dispersed internationally.
Video Images © Teck Cominco & Nyrstar
