Ferrite count procedure
Ferrite count procedure
(OP)
Hello!
I am a QC in welding. I have 321 stainless steel that requires ferrite count at fabrication. Ferritescope instruments are available. However, how can I be sure that testing by third parties has been done correctely. Is there any special metal preparation to extract a very close count by a Ferritescope of between 3% and 8% ferrite content?
Please advise.
Thanking you in advance
Lusitano
I am a QC in welding. I have 321 stainless steel that requires ferrite count at fabrication. Ferritescope instruments are available. However, how can I be sure that testing by third parties has been done correctely. Is there any special metal preparation to extract a very close count by a Ferritescope of between 3% and 8% ferrite content?
Please advise.
Thanking you in advance
Lusitano





RE: Ferrite count procedure
thread330-196616: Ferrite testing
Some interesting discussions here. Also place a search for Ferrite Number in Metallurgy forum and a few more links come up for your reference.
RE: Ferrite count procedure
RE: Ferrite count procedure
Verify your 3rd party inspector is using a calibrated instrument and that he has with him, certified ferrite calibration samples within the applicable range. Although there's not a huge difference in the numbers between % ferrite and ferrite number, verify he's checking in the mode you requested.
Be sure the surfaces being tested are clean but other than that we don't typically do a lot of surface prep prior to testing.
If you have a lot of this to do, I'd recommend your company purchase its own instrument. Many third party inspectors don't do a lot of ferrite testing so you'll need to decide how comfortable you are in turning this inspection over to them.
RE: Ferrite count procedure
RE: Ferrite count procedure
I also like the idea of purchasing your own instrument and a set of calibration standards.
You can use your calibration standards to verify practically any instrument used the NDT group.
The present day intrinsically safe meter of today sure beat the mechanical lift off instruments.