Appearance of Recrystallization Maclas in an Archaeological Piece of Steel from the Northern Necropolis of Cordoba (Spain) (1st Century)

摘要

Slow diffusion at room temperature over long periods of time (centuries and millennia) rewrites the different heat treatments suffered by a steel. With the precipitation of iron carbides, it redraws all those places in the steel where there have been some kind of marks of the thermal treatments suffered: twins, grain limits, etc. These iron carbides draw perfectly these places. In this work this fact has been visualized in one of the iron nails that appeared in a tomb from the 1st century A.D. in the Northern Necropolis of Cordoba in the Roman Baetica. It is one of the many steel artifacts that allow us to see these metallurgical phenomena that we could not easily reproduce today. The metallographic techniques used have been the Conventional Optical Microscopy and the Scanning Electron Microscope.