Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Compression-Fatigue, Elastic Modulus, and Thermal Contraction of Insulated Conduit Arrays of ITER CS Modules



Timothy S. Weeks, Joseph D. McColskey, Richard Reed, Robert Walsh, N. Martovetsky


Abstract- Compression-fatigue tests at 76 K were conducted to compare two insulation systems (epoxy resin impregnated glass/Kapton) for use in the ITER Central Solenoid modules. Test samples consisted of insulated conduits that were stacked in 4 x 4 arrays. The thermal contraction (295-76 K) prior to fatigue, elastic modulus during fatigue, and the structural integrity of the insulation were measured and assessed at the NIST large-scale test facilities. The maximum cyclic stress of 72 MPa, minimum stress of 25 MPa, and 1.2 x 106 cycles were used to comply with ITER design objectives. Thermal contraction between 295 and 76 K and the elastic modulus were measured using strain gages and strain-gage extensometers. Calibration of the strain was obtained through the use of an equivalent-size block of 6061-T6 aluminum alloy with known thermal contraction and elastic moduli. Following fatigue, the arrays were cross-sectioned and optically examined for resin-impregnation quality and fatigue cracking tendencies of the insulation systems. The thermal contraction and elastic modulus of cross-sectioned samples were remeasured at NHMFL using different techniques.
Proceedings Title
IEEE Transactions on Applied Superconductivity
Conference Dates
October 7-12, 2012
Conference Location
Portland, OR
Conference Title


compression fatigue, elastic modulus, glass/epoxy composite, thermal contraction, turn insulation


Weeks, T. , McColskey, J. , Reed, R. , Walsh, R. and Martovetsky, N. (2013), Compression-Fatigue, Elastic Modulus, and Thermal Contraction of Insulated Conduit Arrays of ITER CS Modules, IEEE Transactions on Applied Superconductivity, Portland, OR, [online], (Accessed April 16, 2024)
Created January 9, 2013, Updated November 10, 2018