“Scarcely a week (or a year) goes by without the subject ‘of Rare
Earth Elements’ cropping up. Rare Earths are the 17 strange sounding elements
squeezed into the periodic table between the Alkaline Earths and the Transition Metals.” RE's the 15 lanthanides plus the chemically similar Scandium and Yttrium FIG1 wrote our Materials World (MW) columnist Craig Durham in Materials Matters June 2011. (cf. below, the Periodic Table from Wikipedia .)
Craig goes on to conclude that Strategic Issues such as Rare Earth Issues require a strategic education policy and strong media communications in order to bring to light the fact that these materials do matter and so encourage our young scientists and technologists to undertake the related - Wealth of Nations challenges.
The use and cost of Rare Earths Elements are of course well known to the iron and steelmaking community as most efficient deoxidants and desulphurising additives to liquid steel. cf. for example
Rare earth additions to steel, by Waudby, P. E. International Materials Reviews, Volume 23, Number 1, 1978 , pp. 74-98(25)
Abstract:
The theory and practice of rare earth additions to steel are reviewed. On the basis of thermodynamic data it is predicted that rare earth elements have a very strong affinity for oxygen and sulphur and are capable of reducing the oxygen and sulphur contents of steel as well as modifying the inclusions remaining after solidification and more recently for use in Air Induction and perhaps in Vacuum Induction Melting ref. Optimizing deoxidation and desuIphurization during vacuum induction melting of alloy 718 pp. 167-170(4) Author: Alexander, J. ,Materials Science and Technology ISSN 0267-0836, Online ISSN: 1743-2847
The story of RE's as strategic materials is summarised in the graphs below:
FIG2.
FIG 3
FIG4
NB The factor of roughly 100 between the two graphs: REE non Chinese reserves/ Chinese production 1.8MT/ 80KT in year 2000 (fig1 & 2 above)
World demand for REE's is estimated at 136,100 tons in 2010, 6 with global production around
133,600 tons annually. (ref 12)
FIG 5 & 6 below RE demand by application
FIG 7 Price (pressure)
For the more avid readers some recent features from Materials World (MW) which motivated this blog post and a small sample of the many background reference materials available via the net are referenced below
Materials World Magazine, 01 Jan 2012,
1-"Critical mass - rare earth elements" _IOM3_The Global Network for Materials, Minerals and Mining Professionals
2-Ions shine on - uses of rare earth ions
3-On the surface - preparation of rare earth metals
Materials World Magazine, 01 August 11
4-Rare earth recovery
Materials World Magazine 01 January 12
7-Not costing the Earth - unconsidered waste materials
Materials World Magazine 01 Jun 2007
The materials comprise 85% zinc, rare earth elements (R) and transition metals (T). These RT2Zn20 compounds can be ‘tuned’ by varying the components with up to 10 different transition metals, such as iron, nickel and ruthenium. For each metal, between seven to 14 rare earth elements can be used. Therefore, up to 140 compounds can be created.
IOM3, 26 Jan 2011
Materials World Magazine, 04 Dec 2011
OTHER
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