Effects of Frequency on Fatigue Behavior of Type 316 Low-Carbon, Nitrogen-Added Stainless Steel in Air nad Mercury for the Spallation Neutorn Source

Journal Article · Sun Jan 01 00:00:00 EST 2006 · Metallurgical and Materials Transactions A

DOI:https://doi.org/10.1007/s11661-006-0161-4· OSTI ID:1003658

Tian, Hongbo ^[1]; Liaw, Peter K ^[1]; Fielden, Douglas ^[1]; Jiang, Liang ^[1]; Yang, Bing ^[1]; Brooks, Charlie Ray ^[1]; Brotherton, M D ^[2]; Wang, Hsin ^[1]

---

1. ORNL
2. University of Tennessee, Knoxville (UTK)

The high-cycle fatigue behavior of type 316 low-carbon, nitrogen-added (LN) stainless steel (SS), the prime-candidate target-container material for the spallation neutron source (SNS), was investigated in air and mercury. Test frequencies ranged from 0.2 to 10 Hz with an R ratio of -1, and 10 to 700 Hz with an R ratio of 0.1. During tension-compression fatigue studies, a significant increase in the specimen temperature was observed at 10 Hz in air, which decreased the fatigue life of the 316 LN SS relative to that at 0.2 Hz. Companion tests in air were carried out, while cooling the specimen with nitrogen gas at 10 Hz in air. In these experiments, fatigue lives were comparable at 10 Hz in air with nitrogen cooling and at 0.2 Hz in air. During tension-tension fatigue studies, a higher specimen temperature was observed at 700 than at 10 Hz. After cooling the specimen, comparable fatigue lives were found at 10 and at 700 Hz. The frequency effect on the fatigue life in mercury was found to be much less than that in air, due to the fact that mercury acts as an effective coolant during the fatigue experiment. Striation spacing on the fracture surface at different test frequencies was closely examined, relative to calculated {delta}K values, during fatigue of the 316 LN SS. Specimen self-heating has to be considered in understanding fatigue characteristics of 316 LN SS in air and mercury.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). High Temperature Materials Lab. (HTML)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 1003658
• Journal Information: Metallurgical and Materials Transactions A, Vol. 37a, Issue 1; ISSN 1073--5623
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AIR
COOLANTS
FRACTURES
MERCURY
NEUTRON SOURCES
NITROGEN
SPALLATION
STAINLESS STEELS
STRIATIONS