Molybdenum
Molybdenum which is another high-melting-point metal is frequently used at Takeishi.
Basic physical properties of Molybdenum
Molybdenum powder
(1)Feature
- ・High melting point metal with melting point of 2600℃
- ・Mechanical strength is high at high temperature
- ・High workability, almost equal to SUS.
- ・Excellent electrical and thermal conductivity.
- ・Low coefficient of expansion
- ・Excellent catalyst
(2)Physical characteristics
| Unit of measurement | Content | |
| Atomic number | 42 | |
| Standard atomic weight | 95.94 | |
| Isotopes of molybdenum | 92,94,95,96,97,98,100 | |
| Crystal structure | Body-centered cubic | |
| Melting point | Elementary substance | 2623℃ |
| Boiling point | Elementary substance | 4827℃ |
| Density | g/cm3 | 10.2 |
| Work function | eV | 4.2 |
| Electrical resistivity | Ω・m×10-8 | 5.2×10-8 |
| ３００Ｋ 5.55 | ||
| ６００Ｋ 13.00 | ||
| １０００Ｋ 23.60 | ||
| １５００Ｋ 34.90 | ||
| ２０００Ｋ 53.30 | ||
| ２５００Ｋ 66.50 | ||
| ３０００Ｋ 73.50 | ||
| Thermal expansion | 1/Ｋ | 5.1×10-6（0-100℃） |
| Vapor pressure | ×1.33Ｐａ | ２０６７℃ 10-6 |
| ２２０７℃ 10-5 | ||
| ２３６７℃ 10-4 | ||
| ２５４７℃ 10-3 | ||
| ２７５７℃ 10-2 | ||
| ２３７７℃ 10-1 | ||
| ３００７℃ 1 | ||
| ３６４２℃ 10 | ||
| Young's modulus | N/mm2 | 3.45×105 |
| Mohs hardness | 5.5 | |
| Vickers hardness | ＭＰａ | 1530 |
| Rigidity | N/mm2 | 1.554×105 |
| Poisson ratio | 0.284（20℃） | |
| Tensile strength | N/mm2 | Φ1.0 diameter： 1079（as drawn）、784（1450℃Anealed） |
| Chemical reaction | Oxgen | Slightly oxidize at 200℃ Form Mo3 at 400℃ |
| Aqueos Vapor | Oxidize over 700℃ | |
| Nitrogen | Form Nitride over 1500℃ | |
| Hydrogen | No chemical reaction | |
| Carbon dioxide | Oxidize over 1200℃ | |
| Dilute Sulfic Acid(110℃) | 2012mm yearly | |
| Concentrated hydrochloric acid(110℃) | 0.337mm yearly | |
| 10% Sulfric acid | 0.106mm yearly | |
| Concentrated Sulfic Acid(110℃) | 0.287 yearly | |
| Nitric acid + Sulfric acid | Rapid corrorsion | |
| Nitric + Hydrofluoric Acid | Rapid corrorsion | |
| Nitric acid + Hydrochloric acid | Rapid corrorsion | |
| Hydrofluoric acid (room temperature) | Corrosion | |
| Sulphur (800℃) | Corrosion | |
| Tungsten | Chemical reaction at 2000℃ | |
| Thorium | Chemical reaction at 1900℃ | |
| Alumina | No chemical reaction at 1900℃ |