Eutectic Ledeburite

The primary eutectic structural mixture of austenite and cementite formed during the solidification of white cast iron at approximately 1147 degrees Celsius.

White cast iron has a certain point when cooling where austenite and cementite combine into a hard structure. If you cool the part too fast after welding, the material becomes glass-hard and cracks can form. So you have to cool it slowly and controlled so the structure doesn't break.

MetallurgieSchweißtechnik