History of Molybdenum
Molybdenum was first discovered in 1778 by a Swedish chemist
named Carl William Scheele. Though Scheele is credited with
the discovery of molybdenum in its elemental (oxide) form,
it was Peter Hjelm who in 1782 first reduced the oxide with
carbon to produced the gray metallic powder which he also
named molybdenum.
In early 1900's. Industrial and Military applications required stronger steels with greater resistance to
corrosion and damage.It was found that molybdenum could
impart an impact resistance similar to tungsten when alloyed
with steel, with less weight. Demand for molybdenum
initiated an intensive search for new sources to insure a
reliable supply. In addition to primary molybdenum mines,
molybdenum is also recovered as a byproduct of copper and
tungsten mining operations. The metal is produced from
purified ammonium molybdate or molybdic trioxide powder
through hydrogen reduction at high temperatures.
Characteristics of Molybdenum
 Molybdenum is a transition metal. In its pure form, it is a
soft, silvery white metal which has one of the highest
melting points (2,623 °C/4,753 °F) of all elements. Though
it has the fifth highest melting point of all of the
elements, it has the lowest coefficient of thermal
expansion, making it a highly sought after component in high
temperature applications.
Molybdenum oxidizes readily at temperatures in excess of
760°C. When exposed to air at this temperature, an oxide
layer sublimes as the base metal reacts with oxygen,
resulting in an oxidation process that resembles smoke. When
properly controlled, the oxide can be recovered and reduced
again to reclaim its molybdenum content. To avoid oxidation
loss however, molybdenum is often utilized in inert or
vacuum environments.
The largest use of molybdenum is as an alloy in the
production of steel and stainless steel. Ultra high strength
steels with up to 8% contained molybdenum can withstand
pressures up to 300,000 pounds per square inch. It also
improves the strength of steel at elevated temperatures. In
alloy applications, molybdenum content varies from 0.5% to
8%, dependent upon desired characteristics. Overall, iron
and steel account for more that 78% of the worlds molybdenum consumption.
Typical Chemical Analysis of Molybdenum powder:
Element |
Wt% |
Al |
0.002 |
C |
0.007 |
Cr |
0.0025 |
Cu |
0.002 |
Fe |
0.01 |
Ni |
0.004 |
W |
0.03 |
Co |
0.002 |
Mg |
0.001 |
Mn |
0.001 |
O2 |
Medium |
Coarse |
0.15 |
0.08 |
Mo |
99.95 Minimum excluding gases |
Typical Physical Properties of Molybdenum powder:
|
Medium* |
Coarse* |
Average Particle Size by Fisher Sub-Sieve Sizer |
FSSS as Supplied |
2.0 – 3.5 |
3.5 – 6.0 |
Porosity as Supplied |
>0.60 |
>0.60 |
Scott Density g/In3 |
12 – 25 |
15 – 30 |
Tap Density g/cc |
1.9 – 3.5 |
2.0 – 4.0 |
Mesh Analysis |
>150 |
0–2% |
>150 |
0–2% |
<150 |
98% Min |
<150 |
98% Min |
If you have any interest in molybdenum powder, please feel free to contact us by email: sales@chinatungsten.com or by telephone:+86 592 5129696.
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