The Materials World, a Focus on Rare Earth ElementsArvid Casler - Carbide Derivative Technologies, Inc. & ASM District 14 Council Chair
First let me tell you about what I decided to exclude from this talk. We're not going to discuss NADCA, NADCAP, AZLA, materials, equipment, or ASM International activities, all of which you can readily find material about on the Web. Rather we will take a practical look at the so called Rare Earth elements, how they are used, how they are increasing in importance, and the worldwide distribution of mining and processing.
Rare Earth Elements are those which are found at the bottom of the periodic table. Many become radioactive, and the Actinide series are either not naturally occurring or are used primarily for nuclear applications. The non-nuclear ones we deal with commercially come from the Lanthanide series, and to these we also include Lanthanum, Yttrium, and Scandium.
What are they? Basically they are metals and are in increasing use as both alloy enhancers, and specialty applications:
Lanthanum is heavily used in optical glass and for fiber optics. Also automotive catalysts, ceramics, phosphors and pigments.
Cerium is used in Misch Metal (flint), catalysts, ceramics, glasses, and as oxides for polishing powders.
Praseodymium finds use in ceramics, glasses, pigments, and in medical instruments such as the CAT scan.
Samarium is found in microwave filters, nuclear applications and together with cobalt for permanent magnet production.
Europium is widely found in the phosphors used for CRT and color display.
Scandium finds use in aerospace, baseball bats, nuclear application, LED lighting, and semiconductors.
Yttrium is used in capacitors, (CRT and Lamp phosphors), Radar, and semiconductor application as well as metallurgical enhancement for high temperature alloys.
Gadolinium finds it way into ceramics, glass, optical and magnetic detection as well as medical image visualization techniques.
Neodymium is used in catalysts, IR filter, Lasers (for color), Permanent magnets, and pigments.
Holmium is used in Ceramics, lasers, and nuclear applications.
The other rare earth elements share similar applications.
There are several growth areas where the importance of rare earth element production is particularly critical.
Transportation: (47% of all REE use in the US)
Diesel fuel additives: (Ce, La)
Hybrid vehicle power (Ni-M-I): (Ce, La)
UV reduction glass: (Ce)
LED display screens and lights: (Eu, Ut, Ce)
Catalytic Converters: (Ce, La)
Metallurgy: (20% of REE use in the US)
Glass Polishing and Ceramics: (11% of use in the US)
Electronics, lighting, and illuminated displays: (10% of use in the US)
Energy:
Wind turbines are currently very expensive, subject to high cost failure, and a technology completely developed in Europe. If Solid State power sources can be developed (eliminating many disadvantages) the will rely very heavily on rare earth elements.
Solar cells: cell efficiency can be doubled by using rare earth elements to utilize the UV portion of the spectrum.
Nuclear power: The big issues here are how to rework ores, and wastes efficiently.
Military Applications:
Virtually every missile relies of Rare Earth Elements for something. Range finding lasers use Nd and others. Rare earth elements are found in all avionics systems, stealth sonar transducers (reverse phase sonar), and radar surveillance.
Strategic defenses such as electronic surveillance, phase array radar (which cannot be jammed) and electronic countermeasures all depend on the properties of rare earth elements and are in service 24/7.
Where are the Rare Earth Element (REE) ores?
The US has a major deposit of Bastnasite at Mountain Pass, California, but the mine has been closed for many years by the efforts of environmentalists. Molycorp (Div of Chevrom) resumed some rare earth separation operations at Mountian Pass and is seeking permits to resume mining. Currently the US imports all of it rare earth element material (mostly from China).
China has by far the largest mine production of REEs, at nearly 33 times the entire rest of the world from Laderitic ore.
Russia has significant deposits of Laderitic Ore, but has not yet become a major source of mined product.
India is currently second to China in world-wide ore production (2%). India has Monazite deposits with all of its REE mining and production operations government owned.
Brazil is third in global production (0.6%).
Australia and Canada are in early stages of REE exploration and production.
Who is processing and Selling refined REEs?
China and Japan are huge in this area. Politics have restricted the US from having any major role. However the US is the second largest user of REE in the world (second to China).
Currently our REE needs are supplied:
91% from China
3.3% from Japan
3% from France
0.5% from Russia
0.5% from Australia
Japan has no actual mining of REE, but they do refine a lot of material primarily originating from Australia.
There are no major technological issues to the consolidation and refining of REE. The major issues are political. All REE ore is radioactive which is the buzzword that restricts operations in the US. Safe and responsible practices can be utilized. Many sources of radiation exist in everyday life which surpass those of REE mining. Drywall (for instance), and television displays are highly radioactive.
The most likely pressure to secure sure supplies of REE materials is likely to come over concerns for defense.