8 páginas, 5 figuras. 6th International Symposium on NDT in Aerospace, 12-14th November 2014, Madrid, SpainT he application of ultrasonic waves to the inspection of aeronautic compone
nts is based on the use of couplants
(water, gel, etc...) to facilitate the propagation of the sensi
ng wave through the material. Although several
solutions have been designed to integrate the use of these couplants and the
NDT operations in different stages
of component life (from production to in-service operation) its use incre
ases the complexity of the process and
the cost of the inspection because in some cases special infrastr
uctures may become necessary.
Some of the research effort developed in the last decades has been a
ddressed to reduce the necessity of couplant
gel or fluids. In this sense, the development of ultrasonic inspection w
heels based on special rubbers with a high
degree of humidity has been proposed and is being commercialized nowadays. How
ever, its use is not allowed in
applications where the condition of completely dry coupling is imperative.
Other tools based on air-coupling
have been also developed but they mainly operate in through transmission arrange
ments and its use is limited to
low frequencies.
T his work examines a new wheel-based tool which can operate in dry condit
ion . It has been developed in the
context of the ICARO Project (Innovación en Composites Avanzados y Rear-
End Optimizado) to provide a
nondestructive inspection solution to be integrated into an Out of Autoclave (
OoA) composite manufacturing
process based on electron beam curing technology layer by layer. T he solution
requires be able to inspect very
thin composite specimens (from 0.5mm) in clean and dry conditions compatibl
e with the manufacturing process.
T o overcome these conditions, a special inspection wheel prototype has bee
n developed that integrates a 5MHz
ultrasonic array transducer composed by 128 elements mounted in a particula
r wedge. T his aperture operates in
pulse-echo and generates an ultrasonic image based on linear scanning beam
forming process and a synthetic
aperture acquisition procedure known as 2R-SAFT .
Inspection results obtained from reference standard of different thic
kness are presented. T hese results are
compared with conventional immersion UT inspections and show the high potentia
l of this inspection wheel for
this special applications.Peer reviewe
