Registration Dossier
Registration Dossier
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 231-143-9 | CAS number: 7440-33-7
Endpoint summary
Administrative data
Description of key information
Tungsten is a solid metal with a grey-white colour with a very high melting point range of: 3390 - 3423 °C. The relative density of tungsten metal at 20 °C is 19.35g/cm³ with a mean particle size distribution of D10, D50, and D90 = 2.64, 6.58, and 15.23 µm, respectively. At 3000 °C the vapour pressure is very low with a result of 1.0E-7 Pa. Dissolution of tungsten metal in distilled water is accompanied by the formation of a non-protective oxide film (Lassner and Schubert, 1999). Tungsten metal dissolution was found to take several days to equilibrate (Dermatas et al, 2004), with dissolution slowing after the first 6 hours. The dissolution of tungsten in the presence of dissolved oxygen was observed to be one order of magnitude larger than the dissolution rate in the absence of dissolved oxygen (Ogundipe et al, 2009). The ending result of water solubility at 25 °C was 16509.0 ug/L. The self-ignition temperature for tungsten metal was reported to be 310 °C (particle size not reported). Also, tungsten metal was tested for self-heating and at the particle size tested (0.6-0.9 µm), classifies as a Self-heating, Category 2 substance under CLP.
Additional information
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
