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VOGT Ultrasonics GmbH
non-destructive testing, services, training, ultrasonic systems, immersion and squirter inspection systems, PROline, digital radiology

13370 views
11:22 Sep-28-2009
ravi prajapati
MPT of Stainless steel

Why Magnetic particle testing is not possible for Stainless steel?

 
12:33 Sep-28-2009

anjafo79

NDT Inspector
Norway,
Joined Aug 2009
204
Re: MPT of Stainless steel In Reply to ravi prajapati at 11:22 Sep-28-2009 (Opening).

most simply put it is not magnetic enough.

 
23:48 Sep-28-2009

Chris Galay

NDT Inspector
Portugal,
Joined Sep 2009
2
Re: MPT of Stainless steel In Reply to ravi prajapati at 11:22 Sep-28-2009 (Opening).

The reason why stainless steel cannot be inspected by magnetic particle testing is that we cannot induce a magnetic field on the material as this is non-magnetic. We need a flux leakage so a magnetic field must be present. I hope this will help in your query.

Chris

 
03:10 Sep-29-2009

Nigel Armstrong

Engineering, - Specialist services
United Kingdom,
Joined Oct 2000
1094
Re: MPT of Stainless steel In Reply to anjafo79 at 12:33 Sep-28-2009 .

Its only the austenitic stainless steels which are incapable of magnetisation. The ferritic stainless steels ARE ferromagnetic. Apply a small permanent magnet to the test-piece if you are uncertain whether a material is austenitic or ferritic stainless steel.

 
00:55 Sep-30-2009

Tom Colter

Engineering,
Bechtel Plant Machinery Inc.,
USA,
Joined Nov 1998
3
Re: MPT of Stainless steel In Reply to ravi prajapati at 11:22 Sep-28-2009 (Opening).

For a good expalanation of which stainless steels are paramagnetic (can't be subjected to MPT) and which ones are ferromagnetic (can be subjected to MPT) go to this link:
Magnetic Stainless Steel or Not

 
01:17 Sep-30-2009

Jim Draper

Consultant, ASNT Level III MT PT RT VT
Draper NDT,
USA,
Joined Jul 2009
99
Re: MPT of Stainless steel In Reply to Tom Colter at 00:55 Sep-30-2009 .

It is true that you can perform mag particle testing on ferritic stainless steels. The easiest method of determining if the material can be mag particle inspected is to see if a permanent magnet is attracted to it. The three elements which are ferromagnetic are iron, nickel and cobalt.

 
07:11 Oct-01-2015
NIMBANNA
Re: MPT of Stainless steel In Reply to ravi prajapati at 11:22 Sep-28-2009 (Opening).

All stainless steel materials are nonferrous hence not possible for magnetise the same. For magnetic particle testing, flux leakage is must which is not possible in this case. Hence Magnetic particle testing is not possible. To find out the defects, we may carry out RT / UT which will suffice the requirements.

 
09:26 Oct-01-2015

S V Swamy

Engineering, - Material Testing Inspection & Quality Control
Retired from Nuclear Fuel Complex ,
India,
Joined Feb 2001
783
Re: MPT of Stainless steel In Reply to NIMBANNA at 07:11 Oct-01-2015 .

Pl. correct your understanding of the subject of stainless steels. All stainless steels are not non-magnetic - ferritic stainless steels and martensitic stainless steels etc. are magnetic. Only austenitic stainless steels in fully annealed condition are non-magnetic (paramagnetic).

Best regards

S V Swamy
Metallurgist and Quality / NDT professional (now retired)

 
13:00 Oct-01-2015
Narayana Prasad.N
Re: MPT of Stainless steel In Reply to NIMBANNA at 07:11 Oct-01-2015 .

I disagree with your statement that all stainless steels are non ferrous
Regards

 
06:47 Feb-20-2017

Hello Sir

Engineering, welding inspector
Tekfen,
India,
Joined Sep 2009
1
Re: MPT of Stainless steel In Reply to Jim Draper at 01:17 Sep-30-2009 .

Hi

Is it possible to perform MPI on Feritic Austenitic steel? pls explain sir

 
08:42 Feb-20-2017

S V Swamy

Engineering, - Material Testing Inspection & Quality Control
Retired from Nuclear Fuel Complex ,
India,
Joined Feb 2001
783
Re: MPT of Stainless steel In Reply to Hello Sir at 06:47 Feb-20-2017 .

Ferritic Austenitic Stainless Steels also called duplex steel could be magnetic. As already explained earlier, check whether the material is magnetic or not using a permanent magnet. If the magnet is attracted to the material, MPT is feasible.

Swamy

 


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