Neodymium, atomic no.: 60, symbol as Nd, weight at 144.24, is the most abundant of the rare earths after cerium and lanthanum. It shows similar characteristics to the other trivalent lanthanides.
Primary applications include lasers, glass coloring and tinting, dielectrics and, most importantly, as the fundamental basis for neodymium-iron-boron (Nd2Fe14B) permanent magnets.
The neodymium-based magnet was first introduced in 1982 simultaneously by Sumitomo Specialty Metals (Japan) and General Motors (USA) and commercialized in 1986. It is used extensively in the automotive industry with many applications including starter motors, brake systems, seat adjusters and car stereo speakers. Its largest application is in the voice coil motors used in computer disk drives.
Neodymium has a strong absorption band centered at 580 nm, which is very close to the human eye's maximum level of sensitivity making it useful in protective lenses for welding goggles. It is also used in CRT displays to enhance contrast between reds and greens. It is highly valued in glass manufacturing for its attractive purple coloring to glass.
Neodymium is included in many formulations of barium titanate, used as dielectric coatings and in multi-layer capacitors essential to electronic equipment.
Yttrium-aluminum-garnet (YAG) solid state lasers utilize neodymium because it has optimal absorption and emitting wavelengths. Nd-based YAG lasers are used in various medical applications, drilling, welding and material processing.