Stiffness Reduction of Woven CFRP and CFRTP Spring under Ultra High Cyclic Fatigue for Vibration Conveyor

Abstract:

This paper investigated the stiffness reduction of the plate spring made of CFRP (Carbon cloth and epoxy) subjected to ultra high cyclic fatigue loading under high relative humidity. For practical uses, this paper proposes a new design which prevents the significant degradation with stiffness change of the plate spring at high humidity. Remarkable stiffness reduction of the plate spring due to cracks and delaminations around inter layer could be prevented by using CFRTP rather than that by using CFRP, when ultra high cyclic loading was applied to the plate spring under high humidity condition.

• Periodical: Advanced Materials Research (Volumes 123-125)
• Pages: 217-220
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.123-125.217
• Online since: August 2010
• Authors: Takahiko Yoshi, Kazuya Okubo, Toru Fujii
• Keywords: Carbon Fiber Reinforced Polymer/Plastic (CFRP), CFRTP, High Humidity, Stiffness Reduction, Ultra High Cyclic Fatigue

References

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[1] 2 1 10 100 1000 Moisture content [%] Fig. 8 Microscopic state of inter layer in CFRTP spring after 8th power of 10 loading 100µm.

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[1] E + 0 6 1 . E + 0 7 1 . E + 0 8 Fig. 7 Reduction rate of frequency of CFRTP spring as a function of number of cycles Fig. 6 Result of water absorption test of CFRTP spring 106 107 108 Number of cycles.

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[1] 2 100 96 92 88 84 100 95 90 85 80 100µm 100µm 100µm 100µm 100µm Time [h] ○ at room humidity ○ at room humidity Frequency / Initial Frequency [%] Stiffness reduction rate [%] ▲ at 95% humidity ▲ at 95% humidity at room humidity at 95% humidity.

DOI: 10.1007/978-1-349-03225-9_13