In millimeter wavelength telescope design and construction, there have been a number of mysterious failures of simple
CFRF-metal joints. Telescope designers have not had satisfactory interpretations of these failures. In this paper, factors
which may influence the failure of joints are discussed. These include stress concentration, material creep, joint fatigue,
reasons related to chemical process and manufacture process. Extrapolation formulas for material creep, joint fatigue,
and differential thermal stresses are derived in this paper. Detailed chemical and manufacturing factors are also discussed.
All these issues are the causes of a number of early failures under a loading which is significantly lower than the strength
of adhesives used. For ensuring reliability of a precision instrument structure joint, the designer should have a thorough
understanding of all these factors.
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