Etching Alloy 625
Etching Alloy 625
(OP)
Hi All,
I am having issues trying to etch an Alloy 625 sample in the laboratory (sample from a 1.25" Dia bar). The structure reveals quite a lot of what i believe is banding of carbides. I am not sure if this is detrimental or beneficial, as we have good tensile results and a pass on a G28 corrosion test.
The issue is when we etch the micro, we cannnot resolve the grain boudaries clearly. The certificate from the supplying mill contains photos with the grain boundaries clearly visible (along with the banding we are seeing), but does not detail the etchant used.
Our laboratory informas me they have tried several times to re-polish and etch, and we have also removed other samples from the parent material but the same issue occurs.
Any advice or suggestions would be greatly appreciated
Thanks
I am having issues trying to etch an Alloy 625 sample in the laboratory (sample from a 1.25" Dia bar). The structure reveals quite a lot of what i believe is banding of carbides. I am not sure if this is detrimental or beneficial, as we have good tensile results and a pass on a G28 corrosion test.
The issue is when we etch the micro, we cannnot resolve the grain boudaries clearly. The certificate from the supplying mill contains photos with the grain boundaries clearly visible (along with the banding we are seeing), but does not detail the etchant used.
Our laboratory informas me they have tried several times to re-polish and etch, and we have also removed other samples from the parent material but the same issue occurs.
Any advice or suggestions would be greatly appreciated
Thanks





RE: Etching Alloy 625
Or
thread330-333389: Inconel 625 etching
Or
http://www.tms.org/superalloys/10.7449/1994/Supera...
RE: Etching Alloy 625
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P.E. Metallurgy, Plymouth Tube
RE: Etching Alloy 625
We have tried the normal etchants we use to no avail.
I have found a couple more exotic etchants which we will try. Failing that, we will contact the mill for the inforamtion and try to replicate in-house
RE: Etching Alloy 625
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P.E. Metallurgy, Plymouth Tube
RE: Etching Alloy 625
That did the trick
RE: Etching Alloy 625
Mixed Acids etch (my old lab tech used to call it "#89") - Acetic, HCl and Nitric with a drop or two of glycerine and allow to "mellow for 5-10 minutes, swab and neutralize/dispose of when done (it does not store) also works well.