The main work objective is the creation of the scientific back-ground for correct determination of a set of requirements to the fabrication material with a high-wearing feature under the droplet impingement erosion. A review of a backward and present state of the art of the national and foreign investigations in the field of the droplet impingement erosion of metal materials is carried out. The main outcome is as follows: insufficient fundamentality of research in this area; limitation of the used theoretical models; one-sided approach of many authors to the phenomenon that combines a whole set of factors of different physical nature. On this background, the author´s concept of the erosive wear process of metal under the influence of two-phase mist flow is presented. Particular attention is paid to a new scientific hypothesis of the active hydrogen effect on the fracture of metal under the hyper-velocity dropwise collisions.
droplet impingement erosion, fatigue failure, cavitation, hydrogen wear, steam turbine blades, metal alloys, anti-erosive protection.
Тепловой метод генерации энергии в настоящее время занимает доминирующее положение среди существующих способов производства электроэнергии, покрывая около 70% общего мирового объема потребления. Большинство экспертных оценок сходится к тому, что, по крайней мере до середины текущего столетия ситуация вряд ли существенно изменится [1]. Устойчивости такого положения в глобальной энергетике способствует ряд факторов. Большая часть из них хорошо известна [2]. Например, доступность и достаточность сырьевой базы тепловой энергетики; её технологическая и эксплуатационная надежность; постоянно прогрессирующий рост КПД теплоэнергетических установок, достигший в настоящее время для ПГУ уровня 55–60% (полвека назад он составлял чуть выше 30%). Однако есть факторы, не менее значительные, но «не лежащие на поверхности». К ним следует отнести две взаимосвязанных проблемы: глубина исследованности физических процессов, происходящих при работе энергетического оборудования, и обеспеченность энергетики надежными конструкционными материалами. Тесная взаимозависимость этих сфер очевидна — оптимальность материаловедческого решения определяется полнотой комплекса требований к материалам для изготовления оборудования и конструкций. Этот тезис может быть проиллюстрирован на примере лопаточного аппарата паровых турбин.
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