Journal of Materials Science

, Volume 10, Issue 2, pp 234–242 | Cite as

The compression strength of unidirectional carbon fibre reinforced plastic

  • N. L. Hancox
Papers

Abstract

A simple compression test, suitable for quality control measurements on unidirectional carbon fibre composite, is described. The specimen, a plane bar, with aluminium end tabs attached, is compressed by applying shear forces over the ends. With either type 1 or type 2 treated fibre the failure mode is one of shear over a plane at approximately 45° to the fibre axis. With untreated type 1 material failure is due to delamination. The variation of the compression strength of treated material with fibre volume loading is linear, the values being considerably below those predicted by buckling theory. Increasing void content causes a steady decrease in compression strength, and off-axis strength values are above those given by the maximum work criterion. The present work supports the recently proposed view that the compression strength of unidirectional carbon fibre composites at room temperature is not governed by fibre buckling but is related to the ultimate strength of the fibre.

Keywords

Compression Test Fibre Volume Compression Strength Fibre Axis Void Content 

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Copyright information

© Chapman and Hall Ltd. 1975

Authors and Affiliations

  • N. L. Hancox
    • 1
  1. 1.Process Technology Division, UKAEA Research GroupAEREHarwell, DidcotUK

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