Thermophysical property and pore structure evolution in stressed and non-stressed neutron irradiated IG-110 nuclear graphite

Journal Article · Mon Aug 01 00:00:00 EDT 2016 · Journal of Nuclear Materials

DOI:https://doi.org/10.1016/j.jnucmat.2016.04.042· OSTI ID:1290395

Snead, Lance; Contescu, Christian I.; Byun, Thak Sang; Porter, Wallace D.

The nuclear graphite, IG-110, was irradiated with and without a compressive load of 5 MPa at ~400 *C up to 9.3E25 n/m2 (E > 0.1 MeV). Following irradiation physical properties were studied to compare the effect of graphite irradiation on microstructure developed under compression and in stress-free conditions. Properties included: dimensional change, thermal conductivity, dynamic modulus, and CTE. The effect of stress on open internal porosity was determined through nitrogen adsorption. The IG-110 graphite experienced irradiation-induced creep that is differentiated from irradiation-induced swelling. Irradiation under stress resulted in somewhat greater thermal conductivity and coefficient of thermal expansion. While a significant increase in dynamic modulus occurs, no differentiation between materials irradiated with and without compressive stress was observed. Nitrogen adsorption analysis suggests a difference in pore evolution in the 0.3e40 nm range for graphite irradiated with and without stress, but this evolution is seen to be a small contributor to the overall dimensional change.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1290395
• Report Number(s): PNNL-SA-118130; 830403000
• Journal Information: Journal of Nuclear Materials, Vol. 476; ISSN 0022-3115
• Publisher: Elsevier
• Country of Publication: United States
• Language: English