Detection of layup errors in prepreg laminates using shear ultrasonic waves

David K. Hsu; Brent A. Fischer

doi:10.1117/12.259209

15 November 1996 Detection of layup errors in prepreg laminates using shear ultrasonic waves

David K. Hsu, Brent A. Fischer

Proceedings Volume 2948, Nondestructive Evaluation for Process Control in Manufacturing; (1996) https://doi.org/10.1117/12.259209
Event: Nondestructive Evaluation Techniques for Aging Infrastructure and Manufacturing, 1996, Scottsdale, AZ, United States

Abstract

The highly anisotropic elastic properties of the plies in a composite laminate manufactured from unidirectional prepregs interact strongly with the polarization direction of shear ultrasonic waves propagating through its thickness. The received signals in a 'crossed polarizer' transmission configuration are particularly sensitive to ply orientation and layup sequence in a laminate. Such measurements can therefore serve as an NDE tool for detecting layup errors. For example, it was shown experimentally recently that the sensitivity for detecting the presence of misoriented plies is better than one ply out of a 48-ply laminate of graphite epoxy. A physical model based on the decomposition and recombination of the shear polarization vector has been constructed and used in the interpretation and prediction of test results. Since errors should be detected early in the manufacturing process, this work also addresses the inspection of 'green' composite laminates using electromagnetic acoustic transducers (EMAT). Preliminary results for ply error detection obtained with EMAT probes are described.

Citation Download Citation

David K. Hsu and Brent A. Fischer "Detection of layup errors in prepreg laminates using shear ultrasonic waves", Proc. SPIE 2948, Nondestructive Evaluation for Process Control in Manufacturing, (15 November 1996); https://doi.org/10.1117/12.259209

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available