Molybdenum (Mo) is a critical transition metal that plays an indispensable role in modern industry and technology. Known for its extremely high melting point, outstanding strength at elevated temperatures, and resistance to corrosion, molybdenum is widely used in steelmaking, aerospace, energy production, and the chemical industry. Beyond its applications in metallurgy, molybdenum compounds—such as molybdenum disulfide (MoS₂)—are vital in lubrication, catalysis, and electronics. This guide provides a systematic overview of molybdenum, including its history, occurrence, properties, applications, advantages and disadvantages, and comparisons with other metals.
Basic Information
What is Molybdenum?
Molybdenum (Mo) is a silvery-gray transition metal with atomic number 42, located in Group 6 of the periodic table. It is known for its very high melting point, excellent strength at elevated temperatures, and corrosion resistance, making it an important element in metallurgy, energy, and chemical industries.
Another term for Molybdenum
It is often referred to as Mo element or molybdenum metal.
Is Molybdenum a metal?
Yes, molybdenum is a typical metal with metallic luster, high strength, and good electrical and thermal conductivity.
Is Molybdenum a transition metal?
Yes. Molybdenum is a transition metal, commonly exhibiting oxidation states of +4 and +6, allowing it to form many stable compounds and alloys.
History and Sources
History of Molybdenum
Molybdenum was first identified as a distinct element in 1778 by Swedish chemist Carl Wilhelm Scheele and later isolated in 1781 by Peter Jacob Hjelm.
Originally, it was often confused with lead due to similarities in appearance of their ores.
Sources of Molybdenum
Molybdenum is primarily found in the mineral molybdenite (MoS₂), the chief ore for industrial production.
It rarely occurs in pure metallic form in nature.
How is Molybdenum produced?
- Mining – Extraction of molybdenite ore.
- Ore processing – Crushing, flotation, and concentration.
- Roasting – Molybdenite is roasted in air to produce molybdenum trioxide (MoO₃).
- Reduction – MoO₃ is reduced with hydrogen to obtain pure molybdenum powder.
- Processing – Compacted and sintered into ingots, rods, plates, or used to produce alloys.
Appearance and Physical/Chemical Properties
Appearance
Molybdenum is a silvery-gray metal with high strength and a slightly bluish tint.
Color
Silvery-gray with metallic luster.
Physical Properties
| Property | Value |
| Density | 10.28 g/cm³ |
| Melting Point | 2623 °C |
| Boiling Point | 4639 °C |
| Hardness | High, but tougher than tungsten |
| Magnetism | Non-magnetic |
| Conductivity | Good electrical and thermal conductivity |
Chemical Properties
- Forms stable oxides (e.g., MoO₃), resistant to corrosion in many environments.
- Shows multiple oxidation states, mainly +4 and +6.
- Resistant to non-oxidizing acids but can dissolve in oxidizing acids.
- Compounds are widely used in catalysts, lubricants, and pigments.
Types of Molybdenum
- Pure molybdenum (metal ingots, powders)
- Molybdenum alloys (e.g., Mo-Ti, Mo-Re, high-speed steels)
- Molybdenum coatings and disulfide (MoS₂) lubricants
Applications and Functions
Uses of Molybdenum
- Steel and alloys: Increases strength, toughness, and corrosion resistance in stainless steel, tool steels, and superalloys.
- High-temperature applications: Used in aerospace, nuclear, and power industries due to its high melting point.
- Chemical industry: Catalyst in petroleum refining, chemical reactions, and production of lubricants (MoS₂).
- Electronics: Thin films, electrodes, and components in semiconductors.
Common Commercial Forms
- Metal rods, plates, foils, and powders
- Ferro-molybdenum (alloy additive)
- Molybdenum disulfide lubricants
- Molybdenum alloys and components
Advantages and Disadvantages
Advantages
- Very high melting point and excellent strength at elevated temperatures
- Good corrosion and oxidation resistance
- Enhances hardness, toughness, and wear resistance in alloys
- Versatile applications across metallurgy, energy, and electronics
Disadvantages
- Relatively expensive due to limited supply
- Pure molybdenum can be brittle at low temperatures
- Requires specialized processing and handling
Is molybdenum rustproof?
Yes. Molybdenum has excellent corrosion resistance, especially in reducing environments, though it can oxidize at very high temperatures in air.
Can molybdenum be welded?
Yes, molybdenum can be welded, typically using TIG welding, but requires careful control to prevent embrittlement.
Comparison with Other Metals
Molybdenum vs Molybdenum Alloys
- Molybdenum: A single metallic element, strong and high-melting but can be brittle.
- Molybdenum alloys: Combined with titanium, rhenium, or steel to improve toughness, strength, and resistance to thermal shock (e.g., superalloys, tool steels).
Molybdenum vs Aluminum
| Property | Molybdenum (Mo) | Aluminum (Al) |
| Density | High (10.28 g/cm³) | Low (2.7 g/cm³) |
| Melting Point | Very high (2623 °C) | Low (660 °C) |
| Hardness | Hard, high strength | Soft, highly ductile |
| Corrosion Resistance | Excellent in reducing environments | Moderate (protective Al₂O₃ film) |
| Conductivity | Good | High |
| Cost | Higher | Lower |
Contact MT.BOLTS
MT.BOLTS specializes in the manufacturing and supply of Steel Fasteners, including screws, bolts, nuts, and washers. Our products conform to international standards (ANSI / ASTM / DIN / ISO / JIS) and are available in various materials, dimensions, and surface finishes.
Contact us today to learn more about fasteners and to procure high-quality products. Our technical team is ready to provide expert support and custom selection solutions.
