Page 163 - Fiber Fracture

148 P.K. Gupta

Bare P

yCoated

$8 i

6 #

I
5.0 I I I I 1 I I I I
0 20 40 60 80 100
Relative Humidity, %
Fig. 11. Room temperature strength vs. environmental humidity for silica fibers (Armstrong et al., 1997).

- KCal
S 0.35 -
(N+l) Mole

B Otto (1959)
0 ,,}Cameron (1966)

Fig. 12. Temperature dependence of the strength of pristine E-glass fibers; experimental data and prediction
of slow crack growth model (Gupta, 1983).