Properties of Thulium (Tm)
Thulium is a chemical element with the symbol (Tm) and atomic number 69. It is a rare earth metal and a member of the lanthanide series in the periodic table. Thulium is a soft, silvery-gray metal that is often used in various technologies, including medical imaging and lasers.
The following table provides a comprehensive list of thulium (Tm) properties in both SI and US customary/Imperial units at normal temperature and pressure (NTP).
Click on the icon to switch between Metric and Imperial units.
| Physical Properties | Metric |
|---|---|
| Crystal Structure | Hexagonal close-packed (hcp) |
| Atomic Number | 69 |
| Molar Mass | 168.9342 g/mol |
| Density | 9320 kg/m3 |
| Mechanical Properties | Metric |
| Young’s Modulus (E) | 74 GPa |
| Shear Modulus (G) | 30.5 GPa |
| Bulk Modulus (K) | 44.5 GPa |
| Poisson’s Ratio (ν) | 0.213 |
| Thermal Properties | Metric |
| Melting Point | 1545 °C |
| Boiling Point | 1950 °C |
| Thermal Conductivity (27°C) | 16.9 W/m·K |
| Specific Heat Capacity (Cp) (25°C) | 160 J/kg·K |
| Coefficient of Thermal Expansion (αL) (25°C) | 1.33×10-5 1/°C |
| Electrical Properties | Metric |
| Electrical Resistivity | 6.76×10-5 Ω·cm |
Unless stated otherwise, all values are taken at room temperature (approximately 20°C or 68°F) and 1 atm pressure. (1 atm = 101,325 Pa)
Related Pages
References: 1) Cardarelli, François. Materials Handbook: A Concise Desktop Reference. Switzerland: Springer International Publishing, 2018. 2) CRC Handbook of Chemistry and Physics, 97th Edition. United Kingdom: CRC Press, 2016-2017. 3) A.M. Howatson, P.G. Lun, J.D. Todd, P.D. Engineering Tables and Data. United Kingdom: University of Oxford, Department of Engineering Science, 2009.