Gadolinium (Gd)
MATERIAL
OVERVIEW
(From gadolinite, a mineral named for Gadolin, a Finnish chemist.) Gadolinium is obtained from the mineral gadolinite. Gadolinia, the oxide of gadolinium, was separated by Marignac in 1880 and Lecoq de Boisbaudran independently isolated it from Mosander's yttria in 1886.
Gadolinium is found in several other minerals, including monazite and bastnasite, both of which are commercially important. With the development of ion-exchange and solvent extraction techniques, the availability and prices of gadolinium and the other rare-earth metals have greatly improved. The metal can be prepared by the reduction of the anhydrous fluoride with metallic calcium.
Natural gadolinium is a mixture of seven isotopes, but 17 isotopes of gadolinium are now recognized. Although two of these, 155Gd and 157Gd, have excellent capture characteristics, they are only present naturally in low concentrations. As a result, gadolinium has a very fast burnout rate and has limited use as a nuclear control rod material.
As with other related rare-earth metals, gadolinium is silvery white, has a metallic luster, and is malleable and ductile. At room temperature, gadolinium crystallizes in the hexagonal, close-packed alpha form. Upon heating to 1235oC, alpha gadolinium transforms into the beta form, which has a body-centered cubic structure.
The metal is relatively stable in dry air, but tarnishes in moist air and forms a loosely adhering oxide film which falls off and exposes more surface to oxidation. The metal reacts slowly with water and is soluble in dilute acid.
Gadolinium has the highest thermal neutron capture cross-section of any known element (49,000 barns).
Gadolinium yttrium garnets are used in microwave applications and gadolinium compounds are used as phosphors in color television sets.
The metal has unusual superconductive properties. As little as 1 percent gadolinium improves the workability and resistance of iron, chromium, and related alloys to high temperatures and oxidation.
Gadolinium ethyl sulfate has extremely low noise characteristics and may find use in duplicating the performance of amplifiers, such as the maser.
The metal is ferromagnetic. Gadolinium is unique for its high magnetic movement and for its special Curie temperature (above which ferromagnetism vanishes) lying just at room temperature, meaning it could be used as a magnetic component that can sense hot and cold.
Reference: Los Alamos National Laboratory, <http://periodic.lanl.gov/elements/64.html>
GENERAL
PROPERTIES
|
Symbol: |
Gd |
|
Atomic
Number: |
64 |
|
Atomic
Weight: |
157.25 |
|
Density: |
7.9004
gm/cc |
|
Melting
Point: |
1313
oC |
|
Boiling
Point: |
3266
oC |
|
Thermal
Conductivity: |
0.105
W/cm/oK
@ 298.2 oK |
|
Electrical
Resistivity: |
140.5
microhm-cm @ 25 oC |
|
Electronegativity: |
1.1
Paulings |
|
Specific
Heat: |
0.055
Cal/g/oK
@ 25 oC |
|
Heat
of Vaporization: |
72
K-Cal/gm atom at 3266 oC |
|
Heat
of Fusion: |
3.70
Cal/gm mole |
|
Thermal
Neutron Cross Section: |
46000
Barns per Atom |
|
Magnetic
Susceptibility: |
Ferro
10-6
Emu
@ Room Temp |
|
Magnetic
Moment: |
7.95
Bohr Magnetons |
|
Temperature
Coefficient of Resistance: |
0.00176
@ 0 oC
to Room Temp |
TYPICAL ANALYSES
Impurities in ppm
|
Material
/ Purity: |
3N
|
|
La |
7 |
|
Nd |
6 |
|
Tb |
3 |
|
Er |
5 |
|
Lu |
5 |
|
Ca |
20 |
|
Mg |
130 |
|
Ce |
1 |
|
Sm |
5 |
|
Dy |
180 |
|
Tm |
2 |
|
Y |
2 |
|
Si |
2 |
|
Pr |
0.5 |
|
Eu |
0.5 |
|
Ho |
0.5 |
|
Yb |
1 |
|
Fe |
350 |
|
Al |
5 |
GADOLINIUM ROD
|
Material |
Purity |
|
Gadolinium
Rod .250” |
3N |
|
Gadolinium
Rod .500” |
3N |
Additional
diameters can be manufactured in 7-10 days.
Rod is cut to order and sold by the inch.
GADOLINIUM FOIL
|
Material
|
Purity |
|
Gadolinium
Foil .001” |
3N |
|
Gadolinium
Foil .002” |
3N |
|
Gadolinium
Foil .003” |
3N |
|
Gadolinium
Foil .004” |
3N |
|
Gadolinium
Foil .005” |
3N |
|
Gadolinium
Foil .006” |
3N |
|
Gadolinium
Foil .007” |
3N |
|
Gadolinium
Foil .008” |
3N |
|
Gadolinium
Foil .009” |
3N |
Foil is
cut to order and sold by the square inch or square foot.
GADOLINIUM SHEET
|
Material |
Purity |
|
Gadolinium
Sheet .010” to 0.5” |
3N |
Sheet
thicknesses are available in increments of .001”.
Sheet is cut to order and sold by the square inch.
GADOLINIUM SPUTTERING
TARGETS
|
Material |
Purity |
|
Gadolinium
Sputtering Target 2"D X .125"T |
3N |
|
Gadolinium
Sputtering Target 2"D X .250"T |
3N |
|
Gadolinium
Sputtering Target 3"D X .125"T |
3N |
|
Gadolinium
Sputtering Target 3"D X .250"T |
3N |
|
Gadolinium
Sputtering Target 4"D X .125"T |
3N |
|
Gadolinium
Sputtering Target 4"D X .250"T |
3N |
Additional
sizes and sputtering targets produced from compounds are available
upon request.
GADOLINIUM POWDER,
SHOT, PELLETS, & INGOT
|
Material |
Purity |
|
Gadolinium
Chips |
3N |
|
Gadolinium
Pellets .250"D X .250"L |
3N |
|
Gadolinium
Ingot |
3N |
|
Gadolinium
Powder -40 Mesh, Under Oil |
3N |
|
Gadolinium
Powder -40 Mesh, Ampoules Under Dry Argon |
3N |
| Gadolinium
Powder -40 Mesh, Cans Under Dry Argon |
3N |
Powder,
pellets, and ingots are packaged to order and sold by the gram or kilogram.
GADOLINIUM COMPOUNDS
|
Material |
Purity |
|
Gadolinium
Aluminide GdAl2
1/4" Pieces by Down |
2N5 |
|
Gadolinium
Arsenide GdAs 1/4" Pieces by Down |
2N5 |
|
Gadolinium
Boride GdB6
-60 Mesh |
3N |
|
Gadolinium
Bromide GdBr3-xH2O
-60 Mesh |
3N |
|
Gadolinium
Bromide GdBr3
-60 Mesh |
3N |
|
Gadolinium
Chloride GdCl3-xH2O
-60 Mesh |
3N |
|
Gadolinium
Chloride GdCl3
-60 Mesh |
3N |
|
Gadolinium
Fluoride GdF3
1/4"-1/8" Pieces |
3N |
|
Gadolinium
Fluoride GdF3
-60 & -235 Mesh |
3N |
|
Gadolinium
Hydride GdH2-3
-60 Mesh |
3N |
|
Gadolinium
Iodide GdI3 -60 Mesh |
3N |
|
Gadolinium
Nitride GdN -60 Mesh |
3N |
|
Gadolinium
Oxide Gd2O3
-325 Mesh |
3N,
4N5 |
|
Gadolinium
Oxide Gd2O3
1/2" to 1/8" Pieces |
3N |
|
Gadolinium
Selenide Gd2Se3 -100 Mesh |
3N |
|
Gadolinium
Silicide GdSi2
¼" Pieces by Down |
3N |
|
Gadolinium
Sulfide Gd2S3 -200 Mesh |
3N |
|
Gadolinium Telluride Gd2Te3 -20 Mesh |
3N |
|
Gadolinium
Titanate Gd2Ti2O7 -20 Mesh |
3N |
Compounds
are packaged to order and sold by the gram or kilogram.
|