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possible to correctly identify of the fracture types, which helps to increase the efficiency of
AE-diagnostics of structural elements in real time.
Based on the new criterion the applied method of identification of fracture types of
aluminum, aluminum alloys and their welded joints has been developed. Using energy
criterion it has been established that fracture of technically pure aluminum is ductile with
the formation of a large number of the slip bands and the deep pits on the surface. During
fatigue fracture of aluminum alloy 1201-T dominates the brittle fracture which alternates
with plastic deformation and microcracking. The sources of the AE signals during fatigue
fracture of aluminum alloys and their welded joints under quasistatic loading were
identified by energy criterion and fractographic research.
Based on the research results it was shown that the identification of the fracture types
using the energy parameters of the WT of the AE signals makes it possible to correctly
determine the start of the low-temperature creep cracks.
A new method for the identification of the fracture mechanisms of fiber composite
materials based on the energy parameters of continuous and discrete WT has been
developed.
An express method of qualitative ranking of dental polymers and prosthetic
constructions based on the parameters of their brittleness using of the energy criterion of
continuous WT has been created. Experimental investigations have shown that jump-like
macrofracture of the brittle dental materials had been accompanied by microplastic acts,
that was confirmed by the generation of corresponding AE signals. It is established that
the strength of prosthetic tooth-endocrown constructions depends on the strength of the
base (tooth), where the fracture initiates. The fracture of the zirconium dioxide endocrown
confirms this conclusion. The zirconium specimen on the rigid basis has not fractured
although. The construction with metal ceramic endocrown has the least risk of early
fracture during clinical application.

The method of estimation of the state of local hydrogen degradation of materials
using energy and frequency parameters of WT of MAE signals has been created. The
analysis of local features of continuous WT of MAE signals made it possible to obtain
information about the processes of restructuring of the domain structure during the
ferromagnetic magnetization and to diagnose the state of hydrogen degradation of mate-
rials that contacts for a long period of time with the hydrogen-containing environment. It
has been found out that the hydrogen in the structure of the material leads to increasing in
both the energy of the MAE signals and the energy of their dominant frequency bands
determined before the hydrogenating of the ferromagnetic.
Key words: fracture, displacements field, acoustic emission, magnetoelastic acoustic
emission, hydrogen, wavelet transform, fracture types.