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
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.
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.
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
Thanks for the advice, I have now had some luck etching but I am seeing strange areas in the microstructure. I have attached a micrographhttp://files.engineering.com/getfile.aspx?folder=74dedd7d-f902-4512-ac93-5ed0e5e8d011&file=1.jpg
Thanks guys, I done a bit reading up on some of Vander Voorts papers. One strange thing with the samples is MC type carbides are visible in the un etched condition, however, in the areas the material has been deformed they appear to have disperesed very finely/or gone completely! Is this possible!?
Hi,
Could anybody help with a suitable etchant for revealing grain strucutre for grain size determination in Inconel 625, I'm guessing mixed acids is the way to go? I am aware a bit trial and error would be the best solution but as I am waiting for the components I thought I would ask the...
If it had been quenched from above austenitizing temperature there would be no directionality within the grains, in the photomicrograph attached directionality is quite clear. Also unless it was a very thick section you would expect martensite/ferrite in the core.