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Information × Registration Number 0212U001543, 0110U004789 , R & D reports Title High-frequency fatigue of metallic glass investigations. popup.stage_title Head Bakai Aleksandr Stepanovich, Доктор фізико-математичних наук Registration Date 10-02-2012 Organization National Science Center "Kharkiv Institute of Physics and Technology popup.description2 Under the second phase of the project investigated the impact of previous ultrasonic machining on the thermodynamic properties of bulk metallic glasses. Found: an increase in the time of ultrasonic treatment of amorphous alloy to 60 s leads to a significant growth Young modulus and sound for 80 sec leads to his fall, the energy loss fluctuations naturally increases with time of ultrasonic treatment. The temperature at which the observed maximum energy loss fluctuations also naturally increases. The nature of change of internal friction on the temperature the same as the original, and for the voiced samples. Maximum values of temperature and size of internal friction, which was held at the gap samples, higher for alloys that underwent ultrasound treatment. To a temperature of 200 C all investigated samples have a negative coefficient of thermal expansion. Ultrasonic treatment of amorphous alloys significantly reduces the coefficient of thermal expansion. Ultrasonic treatment of amorphous alloys leads to an increase in the coefficient of elasticity. The maximum value of dynamic viscosity increases with time of ultrasonic treatment from 0 s to 40 s and 60 s, the processing for 80 s alloy partially crystallized, so loses the ability to significantly increase the dynamic viscosity when heated. Found that as a result of DMA-research held a partial crystallization of samples, which took place at the expense of the first stage of crystallization. Ultrasound treatment for 40 and 60 with virtually no impact on the glass transition temperature, crystallization and heat of crystallization of amorphous alloy. Samples sounded for 80 s, with higher crystallization temperature and heat of crystallization is much lower compared with the original alloy, indicating its partial crystallization. Ultrasonic treatment was studied amorphous alloy for 40 and 60 seconds will not cause a noticeable effect on the value of activation energy of crystallization. Sound treatment of alloy for 80 s leads to an increase in activation energy of crystallization of the first phase, but the activation energy for the second phase is somewhat reduced. Structural studies of metallic glass were made with high-field emission microscopy methods. Product Description popup.authors Бакай Олександр Степанович Бакай Сергій Олександрович Михайловський Ігор Михайлович Петрусенко Юрій Тимофійович Щерецький Олександр Анатольйович popup.nrat_date 2020-04-02 Close