Lisovets S. Acoustic control of durability of structural-heterogeneous construction polycrystalline materials with the use of nonlinear effects.

Dissertation is devoted development of new facilities of non-destructive acoustic measuring control with the use of nonlinear effects which on the parameters of resilient wave allow to define tensile strength at the break of wares from polycrystalline materials (pressed details, pipes of warmlychangers, high-rate armature et cetera), and give possibility to decrease measuring errors and promote control authenticity. The facilities of measuring control of tensile strength offered in dissertation at a break are based on measuring of relative change phase speed and relative change of absorption resilient wave. With the use of piezoceramics transformers the experimental setting which allows to conduct measuring control of relative change phase speed and relative change of absorption resilient wave is created. The estimation of error of measuring transformation and authenticity of control of tensile strength is executed at a break. The method of measuring control of parameters of resilient wave is resulted, such as a relative change phase speed and relative change of absorption, and also parameter of polycrystalline materials, such as tensile strength at a break.