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 >
bond testing
Career Discussions
Job Offers
Job Seeks
Classified Ads
About NDT.net
Articles & News

550 views
02:44 Jun-28-2007

samoen

Consultant, -
NDT Wide,
France,
Joined Jun 2007
4
bond testing

We would like to test epoxy bounding quality. Do you have an idea about the use of Ultrasonic Phased Array Technology (or other NDT technology) for bond testing and/or bonding strength evaluation.

Regards



 
05:08 Jun-28-2007

Tom Nelligan

Engineering,
retired,
USA,
Joined Nov 1998
390
Re: bond testing What materials are you bonding? Metal, composites, or ceramics? If you are looking at composite bonds, then either conventional or phased array ultrasonic equipment can be used to check presence or absence of bonding. If you are looking at epoxy bonded metal or plastic, the best approach is usually to look at the ringdown envelope from a single element delay line transducer, as described in the attached link. The reason for this is the significant acoustic impedance mismatch between metals or ceramics and epoxies, which leads to large reflections from the bondline even when there is a good bond. The change in amplitude of a single peak between bond and disbond conditions is small, but the change over an envelope of five or six multiples is readily visible. Phased array systems generally do not have the capability of analyzing the slope of a ringdown envelope, so a conventional flaw detector with an appropriate delay line transducer is a good choice.

Amplitude-based ultrasonic tests generally qualify the presence or absence of bonding only, not bonding strength.



 


© 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|