Surface decarburization 1.2210 untreated
Treatment : untreated
Magnification : 500 : 1
Etching medium : 3 % alcoholic nitric acid
Sampling / Specification : transverse
Testing result :
surface decarburization 0,14 mm deep
zone with appearance of ferrite 0,07 mm deep
zone without cementite lattice 0,07 mm deep
For untreated, hypereutectoid, structural and tool steels, the surface decarburization is shown in form of the appearance of ferrite or by lack of cementite on the grain boundaries. For this the gradient of the carbon loss is decisive.
If the material was cooled down faster after the hot forming, the possibility of the determination of the decarburization can be affected. By the fast cooling, the proeutectoid constituent of ferrite or cementite become suppressed.
