Why not diamond blade for steel

At 800 degrees Celsius, the diamond powder will dissolve in iron. Turning ferrous materials using diamond cutting tools , due to heat generated by the friction of diamond

dissolved iron in the head happen "nodulation" phenomenon, resulting tool can not continue to use.
This is due to the crystal structure of diamond and iron determined. In the synthetic diamond single crystal, the Group VIII metal element Fe (iron), Co, Ni, Ru, Rb,

Pd, Cs, Ir, Pt, Cr, Mn, Ta and other 12 elements can be done catalyst materials are or close-packed fcc

Hexagonal structure in which Fe (iron), Co, Ni these three elements closest to the diamond lattice constant of the lattice constant of 3.56 Å. Such a structure at high

temperature and pressure conditions most likely converted to graphite to diamond, but in the atmospheric conditions, a steady state of graphite, diamond

Stone is metastable, these elements of the Diamond blade with anti-catalytic role in transforming the diamond to graphite. Since Fe (iron) at least the d-electrons, and

carbon atoms, which is the stronger affinity, Fe (iron) to generate a stable carbon Fe3C.