Publications
Showing 24 results for Author: Charles S. Hawkins
Aug, 2024
Journal
Evaluation of liquid metal embrittlement of F82H and 4340 steels in liquid lithium
To evaluate the liquid metal embrittlement (LME) susceptibility of F82H, a reduced activation ferritic-martensitic (RAFM) steel, a testing procedure using hollow cylindrical tensile specimens was used. Tensile tests are compared between specimens filled with argon and lithium at 200 °C. To validate the procedure, initial testing was performed on type 4340 steel, which is w…
Jun, 2024
Journal
Mechanical degradation of duplex SiC-fiber reinforced SiC matrix composite tubes under a controlled high-temperature steam environment
This paper describes results from the mechanical evaluation of unirradiated SiC fiber–reinforced SiC matrix composite tubes under a controlled high-temperature steam environment. The experiments were aimed at identifying key material degradation behavior under environments relevant to loss-of-coolant accidents of light water reactors. Mechanical tests of the SiC composite…
Dec, 2023
Journal
Mechanical behavior analysis using small-size graphite disc compression testing with digital image correlation methods
The ASTM International Standard Test Method for Tensile Stress-Strain of Carbon and Graphite (ASTM C749) requires dog-bone shaped specimens. Unfortunately, specimen sizes required in ASTM C749 are much too large for irradiation within a test reactor and are incompatible with irradiation capsule volumes, molten salt degradation facilities, or oxidation apparatus. The ASTM I…
Nov, 2023
ORNL Report
Comprehensive characterization on stress corrosion cracking of SiC composite tubes
Nov, 2023
Journal
Stress rupture of SiC/SiC composite tubes under high-temperature steam
SiC-fiber–reinforced SiC matrix composite cladding for light water reactor fuel elements must withstand high-temperature steam oxidation in a loss-of-coolant accident scenario (LOCA). Current composite designs include an outer monolithic SiC layer, in part, to increase steam oxidation resistance. However, it is not clear how such a structure would behave under high-tempera…
Nov, 2023
Journal
Interaction of beryllium with 316H stainless steel in molten Li2BeF4 (FLiBe)
The increased demand in renewable energy resources has led to a renewed interest in nuclear reactors including a new generation of molten salt reactors. One of the issues encountered in handling of molten chloride or fluoride salts is the inability of metals to form and retain a protective oxide surface layer, generally chromium oxide. The low chromium content, nickel-base…