Back (Edge zone)

1.4021 | X20Cr13 gas-nitrided, fatigue fracture

Numeric designation1.4021
Chemical designationX20Cr13
Stategasnitriert, Schwingbruch

Fatigue fracture on an uncovered but nitrided screw thread. The basic structure is annealed; bainite (ferrite) with spherical cementite. The core hardness is 270 HV0.5.