Rare Earth Metals

タイトルまたは説明

     Rare earths are a series of chemical elements found in the Earths crust that are vital to many modern technologies, including consumer electronics, computers and networks, communications, clean energy, advanced transportation, health care, environmental mitigation, national defense, and many others.

Because of their unique magnetic, luminescent, and electrochemical properties, these elements help make many technologies perform with reduced weight, reduced emissions, and energy consumption; or give them greater efficiency, performance, miniaturization, speed, durability, and thermal stability.

Rare earth-enabled products and technologies help fuel globale conomic growth, maintain high standards of living, and even save lives.
     

Scandium or Sc (*1)

Scandium, a silvery-white metal, is a non-lanthanide rare earth.It is used in many popular consumer products, such as televisions and fluorescent or energy-saving lamps. In industry, the primary use of scandium is to strengthen metal compounds. The only concentrated sources of scandium currently known are in rare minerals such as thortveitite, euxenite, and gadolinite from Scandinavia and Madagascar.

Yttrium or Y (*9)

Yttrium is a non-lanthanide rare earth element used in many vital applications, such as superconductors, powerful pulsed lasers, cancer treatment drugs, rheumatoid arthritis medicines, and surgical supplies. A silvery metal, it is also used in many popular consumer products, such as color televisions and camera lenses.

Lanthanum or La (*7)

This silver-white metal is one of the most reactive rare earth elements.It is used to make special optical glasses, including infrared absorbing glass,camera and telescope lenses, and can also be used to make steel more malleable.Other applications for lanthanum include wastewater treatment and petroleum refining.

Cerium or Ce (*8)

Named for the Roman goddess of agriculture, Ceres, cerium is a silvery-white metal that easily oxidizes in the air. It is the most abundant of the rare earth elements and has many uses. For instance, cerium oxide is used as a catalyst in catalytic converters in automotive exhaust systems to reduce emissions, and is highly desirable for precision glass polishing. Cerium can also be used in iron, magnesium and aluminum alloys, magnets, certain types of electrodes, and carbon-arc lighting.

Praseodymium or Pr (*9)

This soft, silvery metal was first used to create a yellow-orange stain for ceramics. Although still used to color certain types of glasses and gemstones, praseodymium is primarily used in rare earth magnets.  It can also be found in applications as diverse as creating high-strength metals found in aircraft engines and in flint for starting fires.

Neodymium or Nd (*0)

Another soft, silvery metal, neodymium is used with praseodymium to create some of the strongest permanent magnets available. Such magnets are found in most modern vehicles and aircraft, as well as popular consumer electronics such as headphones, microphones and computer discs. Neodymium is also used to make high-powered, infrared lasers for industrial and defense applications.

Promethium or Pm (*1)

Although the search for the element with atomic number *1 began in ***2, it was not until ***7 that scientists conclusively produced and characterized promethium, which is named for a character in Greek mythology. It is the only naturally radioactive rare earth element, and virtually all promethium in the earths crust has long ago decayed into other elements.Today, it is largely artificially created, and used in watches, pacemakers, and in scientific research.

Samarium or Sm (*2)

This silvery metal can be used in several vital ways. First, it is part of very powerful magnets used in many transportation, defense, and commercial technologies. Second, in conjunction with other compounds for intravenous radiation treatment it can kill cancer cells and is used to treat lung, prostate, breast and some forms of bone cancer. Because it is a stable neutron absorber, samarium is used to control rods of nuclear reactors,contributing to their safe use.

Europium or Eu (*3)

Named for the continent of Europe, europium is a hard metal used to create visible light in compact fluorescent bulbs and in color displays.Europium phosphors help bring bright red to color displays and helped to drive the popularity of early generations of color television sets.  Fittingly,it is used to make the special phosphors marks on Euro notes that prevent counterfeiting.

Gadolinium or Gd (*4)

Gadolinium has particular properties that make it especially suited for important functions, such as shielding in nuclear reactors and neutron radiography. It can target tumors in neuron therapy and can enhance magnetic resonance imaging (MRI), assisting in both the treatment and diagnosisof cancer. X-rays and bone density tests can also use gadolinium, making this rare earth element a major contributor to modern health care solutions.

Terbium or Tb (*5)

This silvery rare earth metal is so soft it can be cut with a knife. Terbium is often used in compact fluorescent lighting, color displays,and as an additive to permanent rare earth magnets to allow them to functionbetter under higher temperatures. It can be found in fuel cells designed to operate at elevated temperatures, in some electronic devices and in naval sonar systems. Discovered in ***3, terbium in its alloy form has the highest magnetostriction of any such substance, meaning it changes its shape due tomagnetization more than any other alloy. This property makes terbium a vital component of Terfenol-D, which has many important uses in defense and commercial technologies.

Dysprosium or Dy (*6)

Another soft, silver metal, dysprosium has one of the highest magnetic strengths of the elements, matched only by holmium. Dysprosium isoften added to permanent rare earth magnets to help them operate more efficiently at higher temperatures. Lasers and commercial lighting can use dysprosium, which may also be used to create hard computer disks and otherelectronics that require certain magnetic properties. Dysprosium may also beused in nuclear reactors and modern, energy-efficient vehicles.

Holmium or Ho (*7)

Holmium was discovered in ***8 and named for the city ofStockholm. Along with dysprosium, holmium has incredible magnetic properties.In fact, some of the strongest artificially created magnetic fields are the result of magnetic flux concentrators made with holmium alloys. In addition to providing coloring to cubic zirconia and glass, holmium can be used in nuclear control rods and microwave equipment.

Erbium or Er (*8)

Another rare earth with nuclear applications, erbium can be found in neutron-absorbing control rods. It is a key component of high-performance fiber optic communications systems, and can also be used to give glass and other materials a pink color, which has both a esthetic and industrial purposes. Erbium can also help create lasers, including some used for medical purposes.

Thulium or Tm (*9)

A silvery-gray metal, thulium is one of the least abundant rare earths. Its isotopes are widely used as the radiation device in portable X-rays, making thulium a highly useful material. Thulium is also a component of highly efficient lasers with various uses in defense, medicine and meteorology.

Ytterbium or Yb (*0)

This element, named for a village in Sweden associated with its discovery, has several important uses in health care, including in certaincancer treatments. Ytterbium can also enhance stainless steel and be used to monitor the effects of earthquakes and explosions on the ground.

Lutetium or Lu (*1)

The last of the rare earth elements (in order of their atomic number)has several interesting uses. For instance, lutetium isotopes can help reveal the age of ancient items, like meteorites. It also has applications related to petroleum refining and positron emission tomography. Experimentally, lutetium isotopes have been used to target certain types of tumors.

    

Rare earth elements or rare earth metals are all part of a series in the Periodic Table of Elements called the Lanthanide Series that runs from atomic number *7 to *1. In addition the elements yttrium #*9, thorium #*0 and scandium #*1 are also considered to be rare earth metals because they share similar properties. Uranium, although often associated with rare earth metals, is not technically a rare earth metal.

There are many uses for rare earth metals. They are constantly being used in the nuclear power and nuclear weapons industries for both practical and experimental utilization. Some rare earth metals have found more down to earth applications in metallurgy, ceramics, glass making, dyes, lasers, televisions and other electrical components. The movie industry makes use of several rare earth metals to help produce the high intensity lamps that are needed for movie projectors. Yttrium has been used for decades in a diamond simulant called YAG or yttrium aluminum garnet which has physical properties similar to natural garnets but with a brilliance and fire more similar to diamond. The importance of rare earth metals is most certainly on the rise.