N. Oya, D.J. Johnson /Carbon 39(2001)635-645 the 101..t m Cantilever beam with strain gauges Kink band Fibre Failure 20um 20um Drving stage Kink band formation Kink band ① Splitting 20m Post-kink splitting Fig. 8. In-situ SEM observations for HM fibre (M60J) crystallite size. Therefore, there should be another structur width Lai and length Lal also showed a similar al reason for different compressive strength in these fibres on compressive HM fibres showed lower compressive strength with in- crease of crystallite size, because large crystallites are very 3.3.3. Compressive strength vs. porosity brittle and sensitive in compressive deformation. Crys- Fig. 11 shows the comparison between longitudina Structural parameters obtained from wide-angle X-ray scatterin Lai (nm) 3.14 T1000 M40J 199 7642 N. Oya, D.J. Johnson / Carbon 39 (2001) 635 –645 Fig. 8. In-situ SEM observations for HM fibre (M60J). crystallite size. Therefore, there should be another structur- tallite width L and length L also showed a similar a' ai al reason for different compressive strength in these fibres. effect on compressive strength. HM fibres showed lower compressive strength with in￾crease of crystallite size, because large crystallites are very 3.3.3. Compressive strength vs. porosity brittle and sensitive in compressive deformation. Crys- Fig. 11 shows the comparison between longitudinal Table 4 Structural parameters obtained from wide-angle X-ray scattering d (nm) D (%) L (nm) L (nm) L (nm) p (%) 002 cc a' ai T300 0.347 80.0 2.60 4.98 2.98 19.7 T700S 0.347 80.0 2.66 5.37 3.14 16.5 T800H 0.347 80.0 2.70 5.67 3.05 17.0 T1000 0.347 80.0 2.61 5.34 3.16 16.5 M40J 0.342 46.7 3.47 6.41 5.11 19.9 M50J 0.340 33.3 4.82 7.49 7.02 15.3 M60J 0.339 26.7 6.84 8.38 8.06 13.0