TOMSK, Jan 30 – RIA Tomsk. Scientists of Tomsk Polytechnic University (TPU) with colleagues from Malaysia for the first
time investigated the carbon-carbon composite using a new method –
ultrasound infrared thermography. This allow to find defects in external
parts of missiles and airplanes online with high accuracy, the press
service of the university reported on Wednesday.
It is specified
that composite materials are widely used in aerospace engineering,
shipbuilding and automotive industry due to their high strength with
relatively low mass and resistance to corrosion. However, composites are
vulnerable to external damage, for example, at a hail, collisions with
birds, blows with tools. Defects in such materials are often invisible
and fraught with danger.
Polytechnicians suggested a research
associate of Malaysian Nuclear Agency Mohd Zaki Umar, who had an
internship at the university, to use ultrasonic infrared thermography
method to control the carbon-carbon composite, becose it combines two
approaches: ultrasonic and thermal. The method has not yet been
implemented in the Russian Federation, but has several advantages.
essence of the method is simple: into the test object powerful
introduced ultrasound with a frequency of 20–40 kilohertz – much more
powerful than in traditional ultrasound testing. An ultrasonic wave
propagating in a solid causes friction of the walls of defects,
generating thermal energy. We fix this energy using infrared cameras ...
According to the thermal "print" of defects, one can judge their
location and characteristics", – the head of the "Thermal Control"
laboratory Vladimir Vavilov is quoted.
© РИА Томск. Александра Астафьева
It is noted that as a
result of experiments, the method proved to be very effective for
detecting damage in the carbon-carbon composite, in particular,
so-called "kissing" defects – for example, cracks, the edges of which
are in close contact with each other and which are difficult to detect
with standard ultrasound and x-ray methods.
It is added that TPU –
is one of the few research centers in the Russian Federation where
studies in the field of ultrasonic infrared thermography are conducted.
The research results are published in the Composites Part B: Engineering