Abstract
This paper reports the changes in ultrasonic attenuation and Young's modulus due to heat-treatment and neutronirradiation of polycrystalline carbon. The measurements were made over a frequency range from 2 to 10 MHz. With increase of heat-treatment temperature (HTT) from 1300 to 2800 °C, Young's modulus decreased and the coefficient of ultrasonic attenuation increased, whereas at HTT = 3100°C the ultrasonic attenuation decreased, with a slight attendant decrease in Young's modulus. When the 3100°C-treated specimens were irradiated by fast neutrons, the coefficient of ultrasonic attenuation decreased and Young's modulus increased. These results were discussed in terms of motion of dislocations. The damping constant and dislocation density were roughly estimated to be about 10 −5 dyne · s/cm 2 and 10 11/cm 2, respectively.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
