Study of Simple CFRP-Metal Joint Failure

摘要

In millimeter wavelength telescope design and construction, there have been a number of mysterious failures of simpleCFRF-metal joints. Telescope designers have not had satisfactory interpretations of these failures. In this paper, factorswhich 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 strengthof adhesives used. For ensuring reliability of a precision instrument structure joint, the designer should have a thoroughunderstanding of all these factors.