Ultrasonic (C-scan) and microscopic evaluation of resin transfer molded epoxy composite plates

Date

2005-02-01

Author

KAŞ, Y. ONUR
Kaynak, Cevdet

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One of the main problem in resin transfer molding (RTM) is the formation of microvoids decreasing the mechanical performance of the components. In this study, an ultrasonic inspection method (C-scan) was used to evaluate these microvoids. Composite sample plates were produced by a small laboratory size RTM machine injecting epoxy resin into a flat mold filled with woven carbon fiber layers. In C-scan analysis a certain value of energy loss (dB loss) was selected as the 'operator set level' and further dB losses were considered as 'defect' or 'microvoid'. C-scan inspection indicated that increasing injection pressure above 2 atm increases the number of microvoids leading to decreased mechanical properties. In the second part of this study, optical and electron microscopy were used to examine these microvoids and also failure mechanisms of the samples.

Subject Keywords

Organic Chemistry, Polymers and Plastics

URI

https://hdl.handle.net/11511/45890

Journal

POLYMER TESTING

DOI

https://doi.org/10.1016/j.polymertesting.2004.07.002

Collections

Department of Metallurgical and Materials Engineering, Article

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Citation Formats

Y. O. KAŞ and C. Kaynak, “Ultrasonic (C-scan) and microscopic evaluation of resin transfer molded epoxy composite plates,” POLYMER TESTING, pp. 114–120, 2005, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/45890.