Service-Hotline: +43-1-2936882   Visit us on facebook      

A leading supplier for high purity elements, periodic table display samples for research, education and collection - Living science...
   Home | About us | About the Elements | Terms/conditions | References | Sponsoring |Guestbook | Contact | Deutsch

Hf
Hafnium
Atomic no.:
72
Atom. weight: 178.49
Density: 13.31
Class:
refractory metal
Melting point: 2227°C
Boiling point: 4602°C
Colour: Array
   
Discoverer: Dirk Coster and György K. von Hevesy
Place: Copenhagen, Denmark
Year: 1923

Discovered in 1923 by D. Coster and G.C. von Hevesey in Copenhagen, Denmark. Hafnium is a silvery colored, ductile metal which is found in all minerals containing zirconium. The chemistries of the two metals are similar which makes them difficult to separate, and the properties of each are greatly affected by the presence of the other as an impurity. Both zirconium and hafnium are extracted as the pure metal by reducing the tetrahalide with magnesium, the whole process being carried out under argon as both metals readily combine with other gases (e.g. nitrogen). The abundance of hafnium in the earth's crust is 5.3 ppm. Hafnium will resist corrosion in air due to the formation of an oxide film, although powdered hafnium will burn in air. It is unaffected by alkalis and acids, with the exception of HF. Hafnium can be used to control recrystallization of tungsten filaments but its main application is as control rod material in nuclear reactors due to its ability to absorb neutrons. The ability of hafnium to absorb neutrons means that it can sometimes be an annoying impurity in zironium metal which is used for nuclear engineering.

Source: ©Goodfellow.com

Views: 560880



  entries 1 to 1 from 1 Gallery view   periodic table

  Categories:  
  rods     Cubes     powder     melted beads     Crystal Bars     Discs  
  Acrylic blocks     All categories  

 Rare Hafnium Crystal Bar - 20.48g very nice piece  Art. Nr. 004715  
Rare Hafnium Crystal Bar - 20.48g very nice piece
magnify Click to zoom!

Hafnium Crystal Bar fragment  - 20.48g unique piece

Very nice fragment of crystal bar with nice crystals on its surface. Crystal bars with that special surface are quite rare and hard to find! The piece has a drilled hole!

Amount: 20.48g
Purity : min. 99.9%
Packing: PE-bag
39.00
- tax free

All pictures are copyright protected and may not be used without our permission!

Request information
SOLD!
 

 

smart-elements.com - Last software update from 17.11.2018 - All rights reserved
Idea, Design & Programming © by Juergen Bauer - All rights reserved