周巻き円環を用いた一方向CFRPの引張疲労寿命の推定 Prediction of Tensile Fatigue Life for Unidirectional CFRP by Using Hoop Winding Ring
A prediction method of fatigue strength of polymer composites for an arbitrary frequency, stress ratio, and temperature has been already proposed. The method is based upon the four hypotheses, (A) failure mechanism for CSR (constant strain-rate), creep, and fatigue failure is the same, (B) the same time-temperature superposition principle is valid for all failure strengths, (C) linear cumulative damage law is applicable for specimen failure under monotonic loading, and (D) fatigue strength shows linear dependence on stress ratio. In this paper, tensile CSR, creep, and fatigue strengths in the longitudinal direction of unidirectional CFRP at various loading rates and temperatures were measured by the NOL ring tests. The validity of hypotheses B, C, D, and the applicability of this prediction method were confirmed by creep tests and fatigue tests of different conditions of loading rate and temperature. It was also confirmed that the hypothesis A is not always necessarily for this prediction method through discussions.
- 日本複合材料学会誌 = Journal of the Japan Society for Composite Materials
日本複合材料学会誌 = Journal of the Japan Society for Composite Materials 25(1), 16-22, 1999-01-15
JAPAN SOCIETY FOR COMPOSITE MATERIALS