Len:

This is the first e-version of data I have. It comes from my ITER “final” report. It plots shear/compression stress from the CS analysis as single dots for each finite element, with appropriate multipliers for the points around the hollow square conductors. The corners of the conductors were excluded. The shear compression allowables represented by the lines came from Rui Vieira and Dick Reed and the home teams for the other parties. The baseline (lowest) allowable was for interleaved glass/prepreg and standard Kapton. The data comes from irradiated samples,  static(4K) tests and fatigue tests at ( I thought 4 but maybe 80K). I haven’t found the original data yet, Early versions were originally summarized in a database that was a part of the criteria document or Appendix C. However the complete results of the tests were not available until the end of the EDA, and the US data came in one half of the expectation – the attached plot is for these last results, and show how we were scrambling to  find a way to qualify the coil. The “fog” plot was intended to show how much of the volume of the coil was below the allowable, and how the better etched Kapton systems were performing. I do not believe the US ever tested the etched Kapton. You can see that removing the Kapton and just using VPI gave the best structural performance, but there was still an expectation of some cracks forming, and the need for the Kapton Barrier remained.

   I am still hunting for more data. -Peter

 

Peter H. Titus, 617 253 1344, FAX: 617 253 0807

MIT-PSFC 185 Albany St Cambridge MA 02139

http://www.psfc.mit.edu/people/titus/