Analysis of Component Contamination from Accelerated Contamination Testing of Five-Year Vuilleumier Cryocooler.
Abstract
Unit S2 of the Vuilleumier Cryocooler Program has undergone accelerated contamination testing at twice the service speed and approximately three times the service pressure expected in a normal unit. Debris samples were obtained from all areas of the cooler; samples of regenerator balls were collected from the second and third stages only. The debris has been characterized by an investigative analysis using the analytical techniques of X ray diffraction, Fourier transform infrared spectroscopy (FTIR), ion microprobe mass analysis (IMMA), and scanning electron microscopy/energy dispersive X ray spectroscopy (SEM/EDXS) with image analysis. Most of the particulates appear to be metal fluorides except on the first and second stage cold rider areas where silicates predominate. When observed in the SEM the balls appear to have a film on them. When examined in the IMMA, Silicon, Fluorine, Lead, Tin, and Antimony can be identified in the second stage while in the third stage, Si, F, Pb, and Sb are present. In addition, Iron and Chromium were observed on both samples. All of the analyses are consistent with a corrosion mechanism of wear.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 05, 1987
- Accession Number
- ADA177203
Entities
People
- D. C. Cranmer
- E. J. Watts
- G. A. To
- N. Marquex
- P. M. Adams
Organizations
- The Aerospace Corporation