Hafnium Powder, Hf

Hafnium for silver gray metal, metallic luster; There are two variants of the hafnium
metal: hafnium is a hexagonal dense packing variant (1750℃) with a higher transition
temperature than zirconium. Hafnium metal has allotropic variants at high temperature.
Hafnium metal has a high neutron absorption cross section and can be used as a
control material for reactors.
The crystal structure can be divided into two types: hexagonal dense packing (-) when
the temperature is below 1300℃; Above 1300℃, is the body center cubic (- formula).
A plastic metal that becomes hard and brittle in the presence of impurities. Stable in
the air, darkens only on the surface when burned. A filament can be ignited by the
flame of a match. Zirconium like in nature. Not water, dilute acid or strong alkali action,
but easy to dissolve in aqua aqua and hydrofluoric acid. It has a +4 valence in the
compound. Hafnium alloy (Ta4HfC5) is known to have the highest melting point
(about 4215℃).
Crystal structure: The cell is hexagonal
CAS no. | 7440-58-6 |
Melting point | 2 227℃ |
The boiling point | 4602℃ |
The density of | 13.31g/cm3(20℃) |
Content in the Crust (PPM) | 5.3 |
Elements in the sun :(parts per million) | 0.001 |
Element content in seawater :(PPM) | 0.000007 |
Mohs hardness | 5.5 |
The rate at which sound travels (m/S) | 3010 |
Quality of proton | 1.20456E-25 |
Proton relative mass | 72.504 |
Chemical properties
Hafnium is very similar to zirconium in chemical properties. It has good
corrosion resistance and is not easy to be attacked by common acid base
aqueous solution. It is easily soluble in hydrofluoric acid and forms a
fluorinated complex. At high temperature, hafnium can also combine
directly with gases such as oxygen and nitrogen to form oxides and nitrides.
USES:
Hafnium is useful because it emits electrons easily (eg as a filament for an
incandescent lamp). Alloys of hafnium and tungsten or molybdenum are
used as electrodes for high voltage discharge tubes. Commonly used in
X-ray cathode and tungsten manufacturing industries. Pure hafnium has
plasticity, easy to process, high temperature resistance and corrosion
resistance, is an important material in atomic energy industry. Hafnium
thermal neutron capture cross section is an ideal neutron absorber, which
can be used as control rod and protection device in atomic reactor.
Hafnium powder ACTS as a booster for rockets. Cathodes of X-ray tubes
can be manufactured in the electrical industry. Hafnium alloys can be
used as front guards for rocket nozzles and glider re-entry vehicles,
and HF-TA alloys can be used to make tool steel and resistance materials.
Hafnium is used as an additive element in heat resistant alloys, such as
tungsten, molybdenum, and tantalum. HfC can be used as carbide additive
due to its high hardness and melting point. The melting point of 4TaCHfC
is about 4215℃, which is the highest known chemical compound. Hafnium
is used as an getter in many aeration systems. Hafnium getter removes
oxygen, nitrogen, etc. from the system without gases. Hafnium is often
used as an additive in hydraulic oil to prevent the volatilization of hydraulic
oil in high-risk operations, with a strong anti-volatilization, this characteristic,
so generally used in industrial hydraulic oil. Medical hydraulic oil. Hafnium
is also used in the latest intel45 nanometer processors.