Etch for Austenite in Maraging Steels
Etch for Austenite in Maraging Steels
(OP)
Your assistance on a particular problem would be appreciated and I thank you in advanced.
I am examining a cracked component manufactured from Maraging Steel. The manufacturing process is simply finish machine then solution treatment and age. Before, you ask why it was solution treated because that is the usual as-supplied condition, it was simply a miscommunication and has now been corrected for future batches.
On carrying out metallurgical examination on the part after polishing and etching with Nital 2, an area of size approximately 400micron by 5micron close to the crack initial and adjacent to the surface of the part was seen to be unaffected by the etch. The hardness of this area is around 350-400Hv; much softer than the rest of the section (615Hv). Although I currently do not know how it developed I assume this is austenite - as a quick test to confirm whether this is the case can any one suggest a suitable etchant for Austenite.
Once again thank you for any assistance
I am examining a cracked component manufactured from Maraging Steel. The manufacturing process is simply finish machine then solution treatment and age. Before, you ask why it was solution treated because that is the usual as-supplied condition, it was simply a miscommunication and has now been corrected for future batches.
On carrying out metallurgical examination on the part after polishing and etching with Nital 2, an area of size approximately 400micron by 5micron close to the crack initial and adjacent to the surface of the part was seen to be unaffected by the etch. The hardness of this area is around 350-400Hv; much softer than the rest of the section (615Hv). Although I currently do not know how it developed I assume this is austenite - as a quick test to confirm whether this is the case can any one suggest a suitable etchant for Austenite.
Once again thank you for any assistance





RE: Etch for Austenite in Maraging Steels
I actually cannot find any optical pitures of these alloys, everything is SEM or TEM.
The best ref for these alloys that I have ever found is part of the Cobalt Monograph Series, Cobalt Containing High Strength Steels, pub by CIC, Brusseles, 1974.
These alloys can be very sensitive to thermo-mechanical history. Re-heat treatment can be very problematic.
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Corrosion never sleeps, but it can be managed.
http://www.trenttube.com/Trent/tech_form.htm
RE: Etch for Austenite in Maraging Steels
thread330-49147
Bruv
RE: Etch for Austenite in Maraging Steels
Regards,
Cory
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