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 -
 1589 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

Michel Couture
NDT Inspector,
consultant, Canada, Joined Sep 2006, 868

Michel Couture

NDT Inspector,
consultant,
Joined Sep 2006
868
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

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

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

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

Product Spotlight

#### iProbe - USB Phased Array Probe

Turn your PC, Laptop or Tablet into a powerful 32:64 Phased Array system with our USB powered Phas
...
ed Array iProbe and inspection software package. Perform affordable weld inspection and corrosion mapping inspections with this powerful but small system. The probe has a 100V pulser, 8K PRF, dual axis encoder input and achieves outstanding signal quality.
>

#### A1525 SOLO

A1525 Solo – the most compact and affordable TMF unit with two phased array transducers and 3D v
...
isualization and analysis software in standard delivery set. A compact, ergonomic and easy to handheld Phased Array unit based on Total Focusing Method for easy-going imaging of inspection objects with two-dimensional and three-dimensional visualization and evaluation of inspection results.
>

#### 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.
>

#### NovaScope 6000

The all-digital Novascope 6000 is a portable, ultra-high precision thickness gauge for high-speed
...
thickness measurement. Novascope 6000 has unmatched capabilities and unique features including: •Superior Resolution with high contrast, high-speed color RF display •High pulser voltage •Real-time video output •Increased internal/external data storage •Programmable SetUp features •Battery & AC Powered
>

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