Тип публикации: статья из журнала
Год издания: 2026
Идентификатор DOI: 10.1134/S0020168526700883
Ключевые слова: hydroturbine runners, mechanical property and fracture toughness characteristics, cavitation damage, Brinell hardness measurements, statistical analysis, coefficients of heterogeneity, residual service life of runner blades
Аннотация: The structural heterogeneity and mechanical property characteristics of the material of turbine runners of hydroelectric generating units exhibiting service‑related defects were investigated. Design features of the turbine runners are noted and the metal microstructure is presented. The chemical composition of the steel was determiПоказать полностьюned by laser‑spark emission spectrometry using a portable laser styloscope. Mechanical properties were obtained from static tensile tests on a tensile testing machine. Impact energy and impact toughness were determined from tests of specimens with a U‑shaped notch in impact bending on a pendulum impact tester over the temperature range from +20 to –30°C. Fracture toughness tests were also performed on a testing machine. Specimens for all tests were cut from a fragment of a runner blade. Hardness values were obtained using a portable dynamic hardness tester by the Brinell method on four blades from the suction (non‑pressure) side in zones of cavitation damage. The main operational problems of hydroturbines associated with cavitation damage to the metal are described. The runner blades were provisionally divided into zones according to the degree of cavitation damage. Based on Brinell hardness measurements, mechanical property characteristics, yield strength and ultimate tensile strength, were estimated. Statistical processing of the obtained values was carried out; distribution histograms were constructed and the characteristic probability distribution law determined; coefficients of heterogeneity were calculated and graphs of the statistical distributions of the mechanical property values were plotted.
Журнал: Inorganic Materials
Выпуск журнала: Т.62, №3
Номера страниц: 308-316
ISSN журнала: 00201685
Место издания: Moscow
Издатель: Pleiades Publishing, Ltd.