Page 78 - Engineered Interfaces in Fiber Reinforced Composites

Chapter 3. Measurements of interfacelinterlaminar properties 61

3.3. Interlaminar/intralaminar properties

3.3.1. Introduction

In addition to the direct measurements of fiber-matrix interface properties
discussed in Section 3.2, a number of testing techniques have been devised to assess
the fiber-matrix interface bond quality by inference from the gross mechanical
properties such as interlaminar shear strength (ILSS), translaminar or in-plane shear
strength, and transverse tensile strength. These testing techniques invariably employ

-
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Laboratory
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(b) Laboratory
Fig. 3.15. Interface shear strength, Tb, of (a) untreated and (b) treated LXA5OO carbon fiber-epoxy matrix
system measured at 10 different laboratories and using different testing methods. (0) fiber pull-out test;
(a) microdebond test; (0) fiber push-out test; (A) fiber fragmentation test. After Pitkethly et al. (1993).