What is Molybdenum Silicide?

Author : Trunnano

Update time : 2022-03-15 10:49:08

What is Molybdenum Silicide?
Molybdenum disilicide is an inorganic compound with the chemical formula MoSi2, which is a gray metallic solid. Insoluble in most acids, but soluble in nitric and hydrofluoric acids. The radii of the two atoms are not much different, and the electronegativities are relatively close, and they have properties similar to those of metals and ceramics. Molybdenum disilicide is electrically conductive, and at high temperatures a passivation layer of silicon dioxide can be formed on the surface to prevent further oxidation. It is used in high temperature anti-oxidation coating materials, electric heating elements, integrated electrode films, structural materials, reinforcing agents for composite materials, wear-resistant materials, connecting materials for structural ceramics, etc.
The characteristics of Molybdenum Silicide
MoSi2 is an intermediate phase with the highest silicon content in the Mo-Si binary alloy system, and is a Dalton-type intermetallic compound with a fixed composition. With the dual characteristics of metal and ceramics, it is a high-temperature material with excellent performance. Good high temperature oxidation resistance, the oxidation resistance temperature is as high as 1600℃, which is equivalent to SiC; moderate density (6.24g/cm3); low thermal expansion coefficient (8.1×10-6K-1); good electrical and thermal conductivity high brittle-ductile transition temperature (1000 ℃) below the ceramic-like hard brittleness. Above 1000 ℃, it is soft and plastic like metal. MoSi is mainly used as heating elements, integrated circuits, high temperature anti-oxidation coatings and high temperature structural materials.
In MoSi2, molybdenum and silicon are bonded by metal bonds, and silicon and silicon are bonded by covalent bonds. Molybdenum disilicide is a gray tetragonal crystal. It is insoluble in common mineral acids (including aqua regia), but soluble in mixed acids of nitric acid and hydrofluoric acid. It has good high-temperature oxidation resistance and can be used as heating elements working in high-temperature (<1700℃) oxidizing atmospheres.
In an oxidizing atmosphere, a protective film layer is formed on the surface of the dense quartz glass (SiO2) burned at high temperature to prevent the continuous oxidation of molybdenum disilicide. When the temperature of the heating element is higher than 1700°C, a protective film of SiO2 is formed, fused at a melting point of 1710°C, and SiO2 is fused into molten droplets. Due to the action of extending its surface, it loses its protective ability. Under the action of the oxidant, when the element is used continuously, it forms the form of a protective film again. It should be noted that due to strong oxidation at low temperature, this element cannot be used in a temperature environment of 400-700 °C for a long time.

Molybdenum Silicide Properties
Other Names	molybdenum disilicide, MoSi2 powder
CAS No.	12136-78-6
Compound Formula	MoSi2
Molecular Weight	152.11
Appearance	Gray to Black Powder
Melting Point	1900-2050 °C
Boiling Point	N/A
Density	6.23-6.31 g/cm3
Solubility in H2O	N/A
Electrical Resistivity	0.0000270 - 0.0000370 ohm-cm
Specific Heat	0.437 J/g-°C (23 °C)
Tensile Strength	185 MPa (Ultimate)
Thermal Conductivity	66.2 W/m-K (23 °C)
Thermal Expansion	N/A
Vickers Hardness	900-1200
Young's Modulus	N/A
Exact Mass	153.859261

Molybdenum Silicide MoSi2 Powder CAS 12136-78-6

The applications of Molybdenum Silicide
Molybdenum disilicide is used in high temperature anti-oxidation coating materials, electric heating elements, integrated electrode films, structural materials, reinforcing agents for composite materials, wear-resistant materials, connecting materials for structural ceramics, etc., and is distributed in the following industries:

Energy chemical industry: electric heating elements, high temperature heat exchangers of atomic reactor devices, gas burners, high temperature thermocouples and their protective tubes, melting vessels and crucibles (for melting sodium, lithium, lead, bismuth, tin and other metals) .
Microelectronics industry: MoSi2 and other refractory metal silicides Ti5Si3, WSi2, TaSi2, etc. are important candidate materials for large-scale integrated circuit gate and interconnect films.
Aerospace industry: As a high temperature anti-oxidation coating material, it has been widely and deeply researched and applied. Especially as a material for turbine engine components such as blades, impellers, combustors, tailpipes and seals.
Automobile industry: turbocharger rotors, valve bodies, spark plugs and engine parts for automobiles.

The main supplier of Molybdenum Silicide
Luoyang Trunnano Tech Co., Ltd (TRUNNANO) is a professional silicide powder supplier with over 12 years of experience in chemical products research and development. We accept payment via Credit Card, T/T, West Union, and Paypal. Trunnano will ship the goods to customers overseas through FedEx, DHL, by air, or by sea.
If you are looking for high-quality boron carbide powder, please feel free to contact us and send an inquiry.

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