| Autor: |
Miyano, Yasushi, Nakada, Masayuki, Kudoh, Hiroshi, Muki, Rokuro |
| Zdroj: |
Mechanics of Time-Dependent Materials; Jun2000, Vol. 4 Issue 2, p127-137, 11p |
| Abstrakt: |
This paper is concerned with the determination of time andtemperature dependent uniaxial static-strength and fatigue life ofunidirectional carbon fiber reinforced plastics (CFRPs). A novel testsystem has been designed with fan-shaped grip ends to secure the CFRPstrands. Constant temperature is maintained in a chamber surrounding thecentral portion of the CFRP strand only. Tensile strengths for carbonfiber reinforced by epoxy resin (CF/Ep) strands under constantstrain-rate (CSR) and fatigue loading were measured at variousloading-rates and temperatures. Corresponding experiments were conductedalso by the conventional split-disk method using the CF/Ep ring as thespecimen. Experimental results from these two methods are compared anddiscussed. The strand-testing method described in this studyprovided excellent results of tensile fatigue life in the longitudinaldirection of unidirectional CFRPs. Advantages of this method are thesmall size of the apparatus and its uniaxial state of stress in the testportion of the specimen. Fatigue lives in tension of CF/Ep strands weremeasured at a single frequency and various temperatures. Assuming thevalidity of the time-temperature superposition principle, a scheme ispresented to draw two sets of master curves for tensile failure stressin fatigue from data measured as previously described. In addition,evidence is presented to support the concept that tensile failure stressin fatigue follows the principle; the shift factor is the same with thematrix resin studied in this work. Further, evidence is presented tosupport that the tensile failure stress in fatigue obeys the principlewith the shift factor for the matrix resin. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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