Dynamic mechanical behavior of stress-graphitized pyrolytic carbon following reactor irradiation at 77°K

✍ Scribed by P.R. Blankenhorn; D.E. Kline

• Publisher: Elsevier Science
• Year: 1969
• Tongue: English
• Weight: 1006 KB
• Volume: 7
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(69)90121-3

✦ Synopsis

Stress-graphitized pyrolytic carbon specimens were subjected to reactor irradiation (-1015nvt -fast) while their temperature was maintained near 77°K. The specimen temperature was subsequently held near 77°K while the specimens were transferred into a testing apparatus where the dynamic mechanical properties (DMP) were obtained as a function of temperature from 80" to 750°K. First DMP tests after irradiation between 100" and 300°K revealed an inverse annealing effect in the dynamic elastic modulus with an inflection near 160°K. Internal friction peaks at 180" and 240°K were also observed in this temperature region. Following annealing of the specimens to 300"K, results for both the internal friction and the elastic modulus changed, compared to the first post-irradiation run. The dynamic mechanical behavior from 100" to 750"K, as determined by the latter tests, appeared to be similar to results previously reported by Taylor, Kline and Walker for room temperature irradiations. This included a large inverse annealing peak in the elastic modulus centered slightly above 500°K.