where expertise comes together - since 1996

Web's Largest Portal of Nondestructive Testing (NDT)
Open Access Database (Conference Proceedings, Articles, News), Exhibition, Forum, Network

All Forum Boards
Technical Discussions >
Ultrasonic NDT for layered materials
Career Discussions
Job Offers
Job Seeks
Classified Ads
About NDT.net
Articles & News

AMDATA Products (WesDyne)
AMDATA is an engineering and technical services firm dedicated to providing standard and custom nondestructive examinations (NDE) products and systems

905 views
11:14 Oct-25-2009
Gustavo
Ultrasonic NDT for layered materials

I would appreciate if someone can guide me in the following issue. I have been studying the possibility of measuring thicknesses and characteristic impedances/sound velocities of layered materials on a substrate by using ultrasonic waves. The main advantage of this analysis is the feasibility of detecting a large number of layers. It looks possible to diagnose materials thicker than 100-micron-thick (perhaps thinner too) and also non-uniform sound velocity patterns, this should work for materials having impedance differences lower than ~30%. Does anyone know any industrial need or application for this analysis?


    
 
17:45 Oct-27-2009

Rolf

Director, Editor, Publisher, Internet, PHP MySQL
NDT.net,
Germany,
Joined Nov 1998
602
Re: Ultrasonic NDT for layered materials In Reply to Gustavo at 11:14 Oct-25-2009 (Opening).

The plastic industries is using already ultrasonic for thickness measurement of layers, but still not in quantity. They are locking always for cheap solutions. Good chance you have in medical and automotive tubing and also the packaging industry has need for good quality control for some productions, e.g., fuel tanks, barrels for dangerous goods. In the databse we have some articles of this issue.

Rolf


    
 
18:38 Oct-27-2009
nishal
Re: Ultrasonic NDT for layered materials In Reply to Gustavo at 11:14 Oct-25-2009 (Opening).

Nondestructive bondline measurement (for example silicon industry - especially if they can measure <100 micron layers ) . Could you possibly send more detail on your analysis?

Nishal
nishalrs@yahoo.co.uk


    
 
12:48 Oct-28-2009
Gustavo
Re: Ultrasonic NDT for layered materials In Reply to Rolf at 17:45 Oct-27-2009 .

Thank you very much for your answer to my question at the NDT forum. It
sounds very interesting, I will search within the fields you mentioned.

Since I am not experienced at this forum, I will appreciate if you can tell
me how to access the database, for looking at the articles you indicated.

Thanks in advance,

Gustavo


    
 
13:52 Oct-28-2009
Gustavo
Re: Ultrasonic NDT for layered materials In Reply to nishal at 18:38 Oct-27-2009 .

Thanks for your answer. Basically, I have worked on the development of a theory that can be applied for reflected acoustic waves. I am convinced that it is possible to measure in a relative easy way the thicknesses and sound velocities (or characteristic impedance) for media composed of many layers and also to characterize graded changes of velocity as a function of depth. I guess that this last case should be useful for certain industrial processes, such as temperature modification; I mean processes that could affect the velocity within the media. The analysis might be advantageous in regard of simplicity and calculation speed. However, it requires wideband ultrasonic measurements, what it is not much conventional. The thickness that could be resolved mainly depends on the freq. range; for the very beginning I assume that the highest freq. will not be higher than 20MHz.


    
 
15:21 Oct-28-2009

Rolf

Director, Editor, Publisher, Internet, PHP MySQL
NDT.net,
Germany,
Joined Nov 1998
602
Re: Ultrasonic NDT for layered materials In Reply to Gustavo at 12:48 Oct-28-2009 .

How to access the database?
Yes you are right, I had to write go to "Search & Archive" in the navigation line. Then you are in the database search form. Now its up to your creativity to find a good search strategy by means of entering good search terms in conjunction with filters. Try to use the filters where to search within the documents: in title, whole doc, keywords.
Further more you can go to "text search" which offers search results in order by relevancy.
You can also go to "keywords" to search or brows the list of keywords.

Good luck!

Rolf


    
 


© NDT.net - The Web's Largest Portal of Nondestructive Testing (NDT) ISSN 1435-4934

Open Access Database, |Conference Proceedings| |Articles| |News| |Exhibition| |Forum| |Professional Network|