Nonlinear mixing of laser generated narrowband Rayleigh surface waves

This research presents the nonlinear mixing technique of two co-directionally travelling Rayleigh surface waves generated and detected using laser ultrasonics. The optical generation of Rayleigh waves on the specimen is obtained by shadow mask method. In conventional nonlinear measurements, the inhe...

Full description

Saved in:
Bibliographic Details
Main Authors: Bakre, Chaitanya, Rajagopal, Prabhu, Balasubramaniam, Krishnan
Format: Conference Proceeding
Language:English
Subjects:
Aluminum base alloys
Higher harmonics
Narrowband
Nonlinearity
Rayleigh waves
Shadow masks
Surface roughness
Surface waves
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:This research presents the nonlinear mixing technique of two co-directionally travelling Rayleigh surface waves generated and detected using laser ultrasonics. The optical generation of Rayleigh waves on the specimen is obtained by shadow mask method. In conventional nonlinear measurements, the inherently small higher harmonics are greatly influenced by the nonlinearities caused by coupling variabilities and surface roughness between the transducer and specimen interface. The proposed technique is completely contactless and it should be possible to eliminate this problem. Moreover, the nonlinear mixing phenomenon yields not only the second harmonics, but also the sum and difference frequency components, which can be used to measure the acoustic nonlinearity of the specimen. In this paper, we will be addressing the experimental configurations for this technique. The proposed technique is validated experimentally on Aluminum 7075 alloy specimen.
ISSN:0094-243X
1551-7616
DOI:10.1063/1.4974545