Platinum
Of the platinum group metals (ruthenium, rhodium, palladium, osmium, iridium, and platinum), platinum is the least rare, and the most widely used, because of its outstanding properties - high melting point, appearance, ductility and exceptional corrosion resistance - platinum, even in the form of thin leaf, is resistant to corrosion and tarnishing on exposure to the atmosphere, including urban sulfur-bearing atmospheres. Some uses for platinum or its alloys include electrical contacts, resistance thermometers, precision potentiometer wire and spinnerettes for synthetic fibers. It is also used as a crucible liner for producing high-purity optical glass and for hydrogenation, as in the production of vitamins and other chemicals.
TYPICAL PROPERTIES :
Boiling Point: 3800 oC
Melting Point: 1769 oC
Density at 20 oC: 21.45 g/cm3 (0.774 lb/in3)
Electrical Resistivity: 98.5 nΩ ⋅ m at 0 oC
Temperature Coefficient: 0.0039/K from 0 oC to 100 oC
Tensile Properties (Annealed at 700 oC):
Tensile Strength: 125 - 165 MPa (18 - 24 ksi)
Proportional Limit: <13.8 MPa (<2 ksi)
Elongation: 30 - 40% in 50mm (2 in)
Tensile Properties (Hard Drawn, 50% Cold Worked):
Tensile Strength: 205 - 240 MPa (30 - 35 ksi)
Elongation: 1 - 3% in 50mm (2 in)
Poisson’s Ratio: 0.39
Elastic Modulus at 20 oC (Annealed at 700 oC):
Tension: Static: 171 GPa (24.5 x 106 psi)
Dynamic: 169 GPa (24.5 x 106 psi)
Elastic Modulus at 20 oC (Hard Drawn, 50% Cold-Worked):
Tension: Static: 156 GPa (22.6 x 106 psi)