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Joe gwinn Joe gwinn is offline
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Default Brittle intermetallic compound makes ultrastrong low-density steel with large ductility

I ran across an interesting metal-related article in Nature magazine.
If this pans out in production, we'll be seeing this in Korean
automobiles real soon now.

"Brittle intermetallic compound makes ultrastrong low-density steel
with large ductility", Sang-Hwon Kim, Hansoo Kim, and Nack J. Kim,
Nature, vol 518, 5 February 2015, pages 77-79, doi:10.1038/nature14144.

Here is the abstract:

Although steel has been the workhorse of the automotive industry since
the 1920s, the share by weight of steel and iron in an average light
vehicle is now gradually decreasing, from 68.1 per cent in 1995 to 60.1
per cent in 2011 (refs 1, 2). This has been driven by the low
strength-to-weight ratio (specific strength) of iron and steel, and the
desire to improve such mechanical properties with other materials.
Recently, high-aluminium low-density steels have been actively studied
as a means of increasing the specific strength of an alloy by reducing
its density (3, 4, 5). But with increasing aluminium content a problem
is encountered: brittle intermetallic compounds can form in the
resulting alloys, leading to poor ductility. Here we show that an
FeAl-type brittle but hard intermetallic compound (B2) can be
effectively used as a strengthening second phase in high-aluminium
low-density steel, while alleviating its harmful effect on ductility by
controlling its morphology and dispersion. The specific tensile
strength and ductility of the developed steel improve on those of the
lightest and strongest metallic materials known, titanium alloys. We
found that alloying of nickel catalyses the precipitation of
nanometre-sized B2 particles in the face-centred cubic matrix of
high-aluminium low-density steel during heat treatment of cold-rolled
sheet steel. Our results demonstrate how intermetallic compounds can be
harnessed in the alloy design of lightweight steels for structural
applications and others.

..http://www.nature.com/nature/journal/v518/n7537/full/nature14144.html

The full article is behind a paywall, but there are other articles on
this, according to google.

Joe Gwinn