Tungsten target

Tungsten targets are mainly used in aerospace, rare earth smelting, electric light source, chemical equipment, medical devices, metallurgical machinery, smelting equipment, petroleum, etc.

physical property

Element symbol: W

Atomic number: 74

Stable isotopes and their percentages: 180 (0.14); 182 (26.41); 183 (14.40); 184 (30.64); 186 (28.41)

Relative atomic mass: 183.85

The electronic layer structure of free atom: 1s22s22p63s23p63d104s24p64d104f145s25p65d46s2

Atomic volume: 9.53 cm3 / mol

Density: 19.35 g / cm3

Crystal structure and lattice constant: α - W: BCC a = 3.16524 nm (25 ℃)

β - W: cubic lattice a = 5.046 nm (stable below 630 ℃)

Melting point: 3410 ± 20 ℃

Boiling point: 5927 ℃

Melting latent heat: 40.13 ± 6.67kj/mol

Sublimation heat: 847.8 kJ / mol (25 ℃)

Heat of evaporation: 823.85 ± 20.9kj/mol (boiling point)

Temperature coefficient of resistance: 0.00482 I / ℃

Electron work function: 4.55 ev

Thermal neutron capture surface: 19.2 B

Elastic modulus: 35000 ~ 38000 MPa (wire)

Torsion modulus: ～ 36000mpa

Bulk modulus: 3.108 × 1011-1.579 × 107t + 0.344 × 103t2 pa

Shear modulus: 4.103 × 1011-3.489 × 107t + 7.55 × 103t2 pa

Compressibility: 2.910-7 cm / kg

There are two forms of tungsten, α and β. At standard temperature and atmospheric pressure, α - type is a stable bcc structure. β - type tungsten can only appear in the presence of oxygen. It is stable below 630 ℃ and converted to α - tungsten above 630 ℃, and this process is irreversible.

Purity: more than 99.95% tungsten

Density: 19.35g/cm3

Surface condition: polished or alkali washed

characteristic

After spraying and sintering, the tungsten target has the characteristics of 99% density or even higher, average transparent texture diameter of 100um or even smaller, oxygen content of 20ppm or less, deflection angle force of 500MPa or so; improving the production of raw metal powder and sintering ability can make the cost of tungsten target stable in the future

A low price. The sintered tungsten target has high density and transparent frame, which can't be achieved by traditional pressing sintering method, and the deflection angle is improved obviously, so that the particles are reduced significantly.