@Ann: Although steel is stronger than aluminum, it's not really too surprising that forged aluminum wheels are stronger than steel wheels made from sheet metal -- the designs and manufacturing processes are completely different. A forged steel wheel would be much stronger than a forged aluminum wheel, but would also weigh a lot more. (Forged steel wheels make sense for railroad cars, but definitely not for on-road applications).
The lifecycle analysis is very interesting. It is very comprehensive, and all of the assumptions seem to be reasonable. It makes a convincing case.
Lou, you're certainly right about the recyclability of aluminum, and steel too to a somewhat lesser extent. But it's also true that LCA has to look at everything. In fact, the latest concept of the life cycle is "cradle-to-cradle", not "cradle-to-grave." CtoC includes that last link in the chain that closes the loop (to mix metaphors) of recycled material going back into the product.
Ann, you mention end of life phases when talking about the life cycle cost analysis. You mention recycling and disposal. Steel and aluminum of this type will certainly be recycled. It has been known for some time that aluminum recycling is extremely effecient. I think it uses about 5% of the energy to recycle aluminum as it does to refine it from bauxite. Steel is also effecient, although I am not sure of the ratio. Steel mini-mills are the most effecient steel mills becuase they use scrap. So, I assume in this case the wheels of both types will be recycled.
It is good, though to see such comprehensive analysis. If you are looking at full lifecycle costs, then you really have to look at everything.
At the JEC Europe 2015 composites show in Paris last month, makers of composite materials, software, and process equipment showed off their latest innovations. This year's show saw some announcements related to automotive applications, but many of the improvements came in the world of aerospace.
The DuPont-sponsored Plastics Industry Trends survey shows engineers want improved performance in a broad range of plastics and better recycling technology. These concerns top even processing enhancements that improve productivity.
Plastics leader SABIC recently announced a global initiative to help its customers take advantage of additive manufacturing (AM) and also advance 3D printing (3DP) technologies in several application areas. The company's plans go way beyond materials, and also include design, processing, and part performance.
A theme that was reflected in several ways at NPE 2015 was the use of 3D printing to assist in, or improve on, injection molding, as well as improvements in 3D printing materials and processes that are making better functional prototypes and end-use parts.
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