Tantalum, Ta

Tantalum is a chemical element with the symbol Ta and atomic number 73. A rare, hard, blue-gray, lustrous, transition metal, tantalum is highly corrosion-resistant and occurs naturally in the mineral tantalite.

Tantalum is dark, dense, ductile, very hard, easily fabricated, and highly conductive of heat and electricity. The metal is renowned for its resistance to corrosion by acids; in fact, at temperatures below 150 °C tantalum is almost completely immune to attack by the normally aggressive aqua regia. It can be dissolved with hydrofluoric acid or acidic solutions containing the fluoride ion and sulfur trioxide, as well as with a solution of potassium hydroxide. Tantalum's high melting point of 3017 °C (boiling point 5458 °C) is exceeded only by tungsten and rhenium for metals, and carbon.

Technical Data
Symbol Ta Density (20°C)/gcm-3 16.65
Atomic number 73 Melting point /°C 2980
No. of naturally occurring isotopes 2 Boiling point /°C 5534
Atomic weight 180.9479 ΔHfus/kJmol-1 24.7
Electronic configuration [Xe]4f145d36s2 ΔHvap/kJmol-1 758.2
Metal radius(12-coordinate)/pm 146 ΔHf(monoatomic gas)/kJmol-1 782(+/-6)
Ionic radius(6-coordinate)/pm V 64 Electrical resistivity  
Ionic radius(6-coordinate)/pm IV 68 (20°C)/μohm cm -12.4
Ionic radius(6-coordinate)/pm III 72 Electronegativity χ 1.5
Evaporation Techniques
Temperature (oC) @Vap. Pressure Techniques Remarks
10-8 Torr 10-6 Torr 10-4 Torr Electron Beam Crucible Coil Boat
1960 2240 2590 Excellent - - - Forms good films

Evaporation Materials
T1-5000-M pellets 6mm diameter x 3mm long
T1-5001-M pellets 6mm diameter x 6mm long
T1-5002-M pieces 3mm
T1-5010-M pellets 3mm diameter x 3mm long
T1-5012-M pieces 3-20mm

The foils are available in either rectangular or circular shape. Please enter width and length or diameter of the required foil.

T1-3003-F 0.004" (0.1mm)
T1-3007-F 0.008" (0.2mm)
T1-10001-P -325 mesh
T1-10002-P 2 microns average
T1-10028-P 50-200 mesh (O 600-800ppm)
T1-2000-R 0.0625" (1.58mm)
T1-2001-R 0.125" (3.175mm)
T1-2002-R 0.250" (6.35mm)
T1-2007-R 0.394" (10mm)
T1-2003-R 0.500" (12.7mm)
T1-2004-R 0.625" (15.88mm)
T1-2005-R 0.750" (19.05mm)
T1-2006-R 1" (25.4mm)
T1-4001-S 0.015" (0.38mm)
T1-4002-S 0.020" (0.5mm)
T1-4003-S 0.030" (0.76mm)
T1-4004-S 0.040" (1mm)
T1-4006-S 0.060" (1.5mm)
T1-4008-S 0.125" (3.175mm)
T1-4009-S 0.250" (6.35mm)
T1-4010-S 0.375" (9.525mm)
T1-4011-S 0.500" (12.7mm)
T1-4012-S 0.750" (19.05mm)
T1-4013-S 1" (25.4mm)
T1-1003-W 0.004" (0.10mm)
T1-1007-W 0.008" (0.203mm)
T1-1011-W 0.020" (0.5mm)
T1-1013-W 0.040" (1.0mm)
T1-1015-W 0.060" (1.5mm)
T1-1017-W 0.080" (2.0mm)