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 -

1646 views
Technical Discussions
Nathan
Nathan
11:40 Jan-27-2009
ULTRASONICS: Shear/Longitudinal Velocity Calculation...

Hi Guys...

What is the calculation to work out the shear wave velocity of a material, if you know the transverse velocity? I know it's approximately half, but is there a formula(e) to work it out?

Hope you can help?

Nathan

 
 Reply 
 
Michel Couture
NDT Inspector,
consultant, Canada, Joined Sep 2006, 893

Michel Couture

NDT Inspector,
consultant,
Canada,
Joined Sep 2006
893
12:56 Jan-27-2009
Re: ULTRASONICS: Shear/Longitudinal Velocity Calculation...
In Reply to Nathan at 11:40 Jan-27-2009 (Opening).

Nathan,

The link below will bring you the Table of Materials Properties for UT inspection. Another source is the Metal's Handbook from the American Society of Materials.

http://www.ndt-ed.org/EducationResources/CommunityCollege/Ultrasonics/Reference%20Information/UT/ut_matlprop_metals.htm

Cheerio's

 
 Reply 
 
Thomas Vogt
R & D, - -
Guided Ultrasonics Ltd, United Kingdom, Joined Apr 2007, 22

Thomas Vogt

R & D, - -
Guided Ultrasonics Ltd,
United Kingdom,
Joined Apr 2007
22
14:38 Jan-27-2009
Re: ULTRASONICS: Shear/Longitudinal Velocity Calculation...
In Reply to Nathan at 11:40 Jan-27-2009 (Opening).

Nathan,

I think you mean longitudinal instead of transverse, but nevertheless, the first thing to realize is that the shear and longitudinal velocities of a material are entirely independent. Together with the density they define the elastic properties of a material, so you cannot work one out purely from the other. You have to look it up in the table as Michel suggested.

However, you can derive a lower (theoretical) limit for the longitudinal velocity: The longitudinal velocity must be greater than the shear velocity times the square root of 2 [in a formula: v_l > v_s*sqrt(2)].

Hope this helps,
Tom

 
 Reply 
 
Richard Freemantle
NDT Inspector, Consultant, R&D
Wavelength NDT Limited, United Kingdom, Joined Nov 1998, 16

Richard Freemantle

NDT Inspector, Consultant, R&D
Wavelength NDT Limited,
United Kingdom,
Joined Nov 1998
16
15:09 Jan-27-2009
Re: ULTRASONICS: Shear/Longitudinal Velocity Calculation...
In Reply to Thomas Vogt at 14:38 Jan-27-2009 .

Hi,

Just to add to Tom's comments, as far as I remember the longitudinal velocity can be directly related to the shear velocity provided you know the Poisson's ratio for the material. Do you have this value for the materials you are interested in ? If so I can try and dig out the equation for you !

Hope this helps,

Regards,

Richard

 
 Reply 
 
James Barshinger
Engineering
General Electric Global Research Center, USA, Joined Aug 2000, 8

James Barshinger

Engineering
General Electric Global Research Center,
USA,
Joined Aug 2000
8
17:58 Jan-27-2009
Re: ULTRASONICS: Shear/Longitudinal Velocity Calculation...
In Reply to Richard Freemantle at 15:09 Jan-27-2009 .

The equation relating shear velocity to longitudinal velocity is CT=CL*sqrt((1-2u)/(2(1-u))) where u=Poisson's ratio.

-Jim

 
 Reply 
 

Product Spotlight

32:128PR PAUT & 2-ch TOFD Flaw Detector: SyncScan 2

●32:128PR PAUT with optional 2-ch TOFD to maximize your efficiency ●Support PR mode for corrosi
...
on inspection ●Multiple solutions for welds & corrosion ●Faster scan speed (Approximately 3 meters/minute) ●Light weight: 4kg only including battery
>

MUSE Mobile Ultrasonic Equipment

The MUSE, a portable ultrasonic imaging system, was developed for in-field inspections of light-weig
...
ht structures. The MUSE consists of a motor-driven manipulator, a water circulation system for the acoustic coupling and a portable ultrasonic flaw detector (USPC 3010). The MUSE provides images of internal defects (A-, B-,C- and D-scan).
>

CIVA 2020 UT Module

CIVA NDE Simulation Software is the world leader of NDT Simulation. The UT simulation Module incl
...
udes: - "Beam computation": Beam propagation simulation - "Inspection Simulation": Beam interaction with flaws or specimens The user can simulate a whole inspection process (pulse echo, tandem or TOFD) with a wide range of probes (conventional, Phased- arrays or EMAT), components, and flaws.
>

VOGT Ultrasonics awarded innovation champion

Let go of the old and try something new. VOGT convinced the jury in the 27th round of the TOP 100
...
innovation competition. Our team is very pleased to officially belong to the TOP 100 in Germany!
>

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