where expertise comes together - since 1996 -

The Largest Open Access Portal of Nondestructive Testing (NDT)

Conference Proceedings, Articles, News, Exhibition, Forum, Network and more

where expertise comes together
- since 1996 -
825 views
Technical Discussions
Jedispin
Jedispin
06:59 Aug-18-2009
Subsurface crack detection by MT in Martensitic Stainsless Steel

Hi,

I would like to have some information regarding subsurface crack detection by MT in Martensitic Stainsless Steel. I would like to know, what is the maximum depth that we can detect such a crack for martensitic stainless steel.

Do a study has been already done regarding subsurface crack detection on different material.

 
 Reply 
 
Michel Couture
NDT Inspector,
consultant, Canada, Joined Sep 2006, 850

Michel Couture

NDT Inspector,
consultant,
Canada,
Joined Sep 2006
850
03:57 Aug-19-2009
Re: Subsurface crack detection by MT in Martensitic Stainsless Steel
In Reply to Jedispin at 06:59 Aug-18-2009 (Opening).

Hi,

I will answer your question assuming that you are inspecting parts of that material on a regular basis. Maybe you should get a Ketos Ring of a similar material. This way, you will be able to properly verify the sensitivity of your system and will know exactly how deep you can go. The drawing can be found in ASTM E1444.

 
 Reply 
 
John Brunk
Engineering, NDT Level III
Self employed, part-time, USA, Joined Oct 1999, 161

John Brunk

Engineering, NDT Level III
Self employed, part-time,
USA,
Joined Oct 1999
161
06:46 Aug-19-2009
Re: Subsurface crack detection by MT in Martensitic Stainsless Steel
In Reply to Jedispin at 06:59 Aug-18-2009 (Opening).

Martensitic stainless steels, including maraging steel that has not been heat
treated to reform a substantial percentage of austenite, has extremely
limited depth of penetration for very low-frequency eddy current inspection.
Based on this I would be surprised if you could detect subsurface defects with
an electromagnetic yoke. With full-wave rectified current and high amperage
and a Ketos-type ring as Michel suggested, you might find an answer that
pleases you. There are both ferromagnetic and non-ferromagnetic forms of
martensite, but the ferromagnetic form structure often predominates, especially
in maraging steels.

 
 Reply 
 

Product Spotlight

Robotic laser shearography enables 100% inspection of complex, flight-critical composite structures

An article in “Composites World Magazine” showcases Non Destructive Testing of aero-structures
...
with Laser Shearography. Over the years Dantec Dynamics has supplied many solutions for the aerospace industry. Referring to specific customer projects several of these cases are examined to outline the advantages of using Laser Shearography for automated defect detection.
>

Varex Imaging Large Field of View (FOV) Digital Detector Arrays (DDAs)

A larger FOV DDA can reduce the space and volume of the X-ray inspection system on the factory floor
...
, enable faster scanning times, better throughput and better resolution images at a lower dose. Customers can also save time and money. With these benefits in mind, Varex Imaging has designed a family of large FOV detectors (4343HE, XRD 1611, 4343DX-I, 4343CT) for our industrial imaging customers.
>

NDTkit RT

NDTkit RT, TESTIA's Digital Radiography software The NDTkit product line software for X-ray analysi
...
s. NDTkit RT is a software benefiting from the Ultis kernel which is dedicated to radiographic image analysis. It offers a set of tools and filtering processes to assist RT operators in finding relevant flaws.
>

Surf-X® Array Probe

Introducing the Surf-X family of flexible Eddy Current Array (ECA) probes. Featuring unique multiple
...
coil sets and proprietary X-PROBE technology, Surf-X array probes can quickly and accurately handle a range of inspection applications, from inspecting corrosion or cracking in pipes, pressure vessels, or tanks, to assessing and sizing cracks in raised welds and friction stir welds.
>

Share...
We use technical and analytics cookies to ensure that we will give you the best experience of our website - More Info
Accept
top
this is debug window