FATIGUE PROPERTIES OF MODIFIED 316LN STAINLESS STEEL AT 4 K FOR HIGH FIELD CABLE-IN-CONDUIT APPLICATIONS

Journal Article · Thu Apr 08 00:00:00 EDT 2010 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3402339· OSTI ID:21371748

Toplosky, V J; Walsh, R P; Han, K ^[1]

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1. National High Magnetic Field Laboratory, Tallahassee, FL, 32310 (United States)

Cable-In-Conduit-Conductor (CICC) alloys, exposed to Nb{sub 3}Sn reaction heat-treatments, such as modified 316LN require a design specific database. A lack of fatigue life data (S-n curves) that could be applied in the design of the ITER CS and the NHMFL Series Connected Hybrid magnets is the impetus for the research presented here. The modified 316LN is distinguished by a lower carbon content and higher nitrogen content when compared to conventional 316LN. Because the interstitial alloying elements affect the mechanical properties significantly, it is necessary to characterize this alloy in a systematic way. In conjunction, to ensure magnet reliability and performance, several criteria and expectations must be met, including: high fatigue life at the operating stresses, optimal stress management at cryogenic temperatures and thin walled conduit to reduce coil mass. Tension-tension load control axial fatigue tests have good applicability to CICC solenoid magnet design, thus a series of 4 K strength versus fatigue life curves have been generated. In-situ samples of 316LN base metal, seam welded, butt welded and seam plus butt welded are removed directly from the conduit in order to address base and weld material fatigue life variability. The more than 30 fatigue tests show good grouping on the fatigue life curve and allow discretionary 4 K fatigue life predictions for conduit made with modified 316LN.

• OSTI ID: 21371748
• Journal Information: AIP Conference Proceedings, Vol. 1219, Issue 1; Conference: International cryogenic materials conference (ICMC) on advances in cryogenic engineering materials, Tucson, AZ (United States), 28 Jun - 2 Jul 2009; Other Information: DOI: 10.1063/1.3402339; (c) 2010 American Institute of Physics; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CARBON
CRYOGENICS
DESIGN
FATIGUE
INTERSTITIALS
MATERIALS TESTING
PERFORMANCE
STAINLESS STEEL-316L
STRAINS
STRESSES
THERMONUCLEAR REACTOR MATERIALS
WELDED JOINTS
ALLOYS
AUSTENITIC STEELS
CARBON ADDITIONS
CHROMIUM ALLOYS
CHROMIUM STEELS
CHROMIUM-MOLYBDENUM STEELS
CHROMIUM-NICKEL STEELS
CHROMIUM-NICKEL-MOLYBDENUM STEELS
CORROSION RESISTANT ALLOYS
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
ELEMENTS
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
HIGH ALLOY STEELS
IRON ALLOYS
IRON BASE ALLOYS
JOINTS
LOW CARBON-HIGH ALLOY STEELS
MATERIALS
MECHANICAL PROPERTIES
MOLYBDENUM ALLOYS
NICKEL ALLOYS
NONMETALS
POINT DEFECTS
STAINLESS STEELS
STEEL-CR17NI12MO3-L
STEELS
TESTING
TRANSITION ELEMENT ALLOYS