Recent content by Mett87

Forgot to mention hardness is 25HRC.

the micrograph below is of a medium carbon steel, the grain size looks too coarse to be bainite - could this be acicular ferrite produced by a 2 stage cooling?

Heres another micrograph etched with modified glyceriga electrolytically to show the precipitates http://s23.postimg.org/5n0ggh293/glycerol.jpg%5b/img%5d%5b/url

HCL/H2O2 nothing else would touch it! Tried gleyceriga and mixed axids.

http://s30.postimg.org/i6ojrebst/image.jpg

Unfortunately I don't have a comparison for after the solution anneal or any data regarding mechanical properties, the section is also too small to perform testing on. Kimkumvijay - that is the paper I referenced.

This was the paper I found http://www.tms.org/superalloys/10.7449/2001/01-5107-345.pdf

I cant find that exact paper, however, I did find one that has suggested M23C6 and M6C type are typically precipitated at the grain boundarys as originally thought. I can't find any reference to the amount of precipitation typical for specific ageing times/temps.

I have a section of In725 that appears to have a nearly continuous carbide network at the grain boundaries. Is this typical for this grade? Heat treatment was:- 1040c for 11hr/air cool 730c for 12hr/furnace cool to 620c hold for 8hr/air cool Hardness 37HRC Thanks in advance.

Isopentane (C5H12) and Liquid Nitrogen slush can be taken down to -256F (-160C) if thats any help?

i was saying i had no luck with the mixed acid etchant. this was etched electrolytically

It appears only on the outer few mm. Would you agree it coukd be possibly from localised heating and slow cooling?

Why don't you just hot mount with a glass/mineral filled epoxy?

Another micrograph showing defects due to cold working? http://files.engineering.com/getfile.aspx?folder=555b11e6-dcae-4d4b-a808-ab3291cdec86&file=2.jpg

Ed, Unfortunately I do not know the background behind the material, also, i dont have the facility for dic or polarized light. metaljon, I have tried with mixed acids etchant with no luck