Hf(Atomic number : 72)

1. Introduce – Metal in the quaternary group with titanium and zirconium in the periodic table – Hf is mainly obtained as a by-product when producing zirconium from Hf ores (zircon, hafnon, albite) (approximate ratio of zirconium to hafnium is 50:1) – Has excellent corrosion resistance by reacting with oxygen to form a surface oxide layer – Hf alloying elements influence : corrosion resistance * Zr and Hf – Zr is always accompanied by Hf in nature – Zr has nearly the same electron and ionic radii as Hf, and other properties such as density, transition temperature, and c...