Влияние дефектов микроструктуры на механические свойства и накопление водорода в стали SS316

Abstract

Получены данные по эволюции дефектной микроструктуры, уровням накопления и температурным интервалам удержания изотопа водорода - дейтерия в аустенитной стали SS316. Показано влияние вакансий, вакансионных комплексов, дислокационных структур, вакансионных и газонаполненных пор на удержание водорода. Изучена корреляция радиационно-индуцированного упрочнения нержавеющей стали SS316 и эволюции ее микроструктуры при облучении в интервале доз 0-25 смещений на атом (сна) при 300 K, а также влияние водорода на эти процессы = Data on the evolution of damage microstructure, as well as accumulation levels and temperature intervals of retention of the hydrogen isotope deuterium in SS316 austenitic steel were obtained. It has been established that vacancy-type defects are the most preferential trapping sites for deuterium atoms at irradiation doses of ~1 dpa (displacement per atom). The development of dislocation structures, vacancy and gas-filled pores is shown and their distribution by size is determined. The dependence of the amount of trapped deuterium atoms on the development of a defect structure upon annealing is determined. An essential hydrogen retention in the traps associated with helium and argon bubbles has been established, that support the data obtained for stainless steels irradiated in light water reactors. The correlation of radiation-induced hardening of SS316 stainless steel and the evolution of its microstructure during irradiation in the dose range of 0-25 dpa at 300 K was studied. It was found that hardening at such doses reaches 75% and saturated at 2 dpa. The greatest contribution to hardening is made by clusters of defects and dislocation loops with a diameter of less than 15 nm. At operating conditions hydrogen affects the hardening at concentrations of ~1 at.%.