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construction materials evaluation. These technologies are based on statistical
processing of back-scattered ultrasonic signals ("structural noise") and tomographical
reconstruction of the damage state of material. The object of the research is the
dependence of the parameters of ultrasonic signal on the parameters of the material
damage state.
The limitation of the existing methods and devices as to the retrieval of
information about spatial distribution of material scattered damage before macro-flows
are formed is found. The expediency of using the back-scattered signal (as it is the most
sensitive as for scattered damage dynamics) is proved.
The acoustic receiving channel of A-Scans registration was analyzed, the model of

the recorded signal was suggested and the processing technologies were developed in
order to consider the acoustic contact factor, amplification, device noise, signal
attenuation while propagation.
The method of ultrasonic back-scattering profile definition along the direction of
ultrasound propagation is developed. The method is based on A-Scan signals
registration and statistical processing. The back-scattering profile is the base of
tomographical reconstruction of material scattered damage.
A new approach to tomographical reconstruction of the curved projections and for
objects with curved boundaries is developed in order to optimize tomographical
reconstruction procedures, to perform statistical processing of the recorded signals and
to obtain back-scattering profile of the material experimentally. This information is the
base of new ultrasonic techniques as to complex structured materials diagnostics before
the flaws are formed but there are already places with scattered damage.
The new ultrasonic technology for the evaluation of the damage state of steel and
alloys of the feed-аКЭОr pТpОХТЧОs Тs НОЯОХШpОН КЧН ЭОsЭОН ОбpОrТЦОЧЭКХХв ТЧ “RШЯЧШ

NPP”. TСО ЭОМСЧШХШРв Тs ЛКsОН ШЧ ЭСО НТsШrНОr level of the tomographical pictures
calculation. The disorder of the tomographical pictures usually is increased with the
material damage state increase.
The new ultrasonic technique of weld joint quality evaluation is developed in order
to perform diagnostics of material in cases where standard techniques (e. g. B-Scan) are
not informative because of the flaws are not formed. The developed technique can be
used for the evaluation of the weld joints uniformity along the joint and symmetry
across the joint and for welding process adjustment. The technique is automated and
can be used for the weld joints monitoring in order to detect the high scattered damage
and further flaw appearance allocations.
The new ultrasonic technique of scattered damage of metal while different types of
loading is developed. The technique is based on multiple recording and compatible
processing of back scattered signal. The compatible processing is based on the
obtaining of back-scattered signal deviations histograms on comparable products and
their comparison in order to evaluate the scattered damage of each product and
resolution of the approach.
The technique of adhesive strength of the gas-thermal coating mapping is
suggested. It is based on the identification of delaminated places in the product using
backscattered signal approach.