PR Jackson et al. / Materials Science and Engineering A 454-455(2007)590-601 Matrix r 90° Fibers 0° Fibers Fig. 12. As-processed N601//A composite from billet B14. Few isolated matrix-rich areas and good matrix infi iber layerare apparent. 5. Concluding remarks 5.l.M 1 The compressive stress-strain behavior of N610/A and N610/M/A composites was investigated and the compressive properties measured at room and elevated temperatures. At temperatures<1100C, the compressive stress-strain behavior of the monazite-containing composite is nearly linear to fail ure; compressive modulus and strength magnitudes are close Fig. 11. As-processed N601/M/A composite from billet B15. Thick matrix to the corresponding tensile values obtained in prior work bands between the fibrous layers are clearly visible. (a) Optical micrograph [53]. Compressive behavior of the N6IO/A composite remains and(b) backscatter SEM image showing matrix-rich areas between fibrous lay. approximately linear to failure at 900C. However, at 1100C, ers and regions devoid of matrix in the 90 fiber layer. Bright white streaks are the compressive stress-strain curve consists of two nearly lin- ear portions with a decrease in slope occurring as the stress Fig. 13. Fracture surfaces of a N6IO//A specimen from billet B 14.(a) Multiple cracks initiate between the layers and (b) several short cracks(arrows)propagate into the 90 fiber layer and self-arrest.P.R. Jackson et al. / Materials Science and Engineering A 454–455 (2007) 590–601 599 Fig. 11. As-processed N601/M/A composite from billet B15. Thick matrix bands between the fibrous layers are clearly visible. (a) Optical micrograph and (b) backscatter SEM image showing matrix-rich areas between fibrous lay￾ers and regions devoid of matrix in the 90◦ fiber layer. Bright white streaks are the monazite coating. Fig. 12. As-processed N601/M/A composite from billet B14. Few isolated matrix-rich areas and good matrix infiltration into the 90◦ fiber layer are apparent. 5. Concluding remarks 5.1. Monotonic compression The compressive stress–strain behavior of N610/A and N610/M/A composites was investigated and the compressive properties measured at room and elevated temperatures. At temperatures ≤ 1100 ◦C, the compressive stress–strain behavior of the monazite-containing composite is nearly linear to fail￾ure; compressive modulus and strength magnitudes are close to the corresponding tensile values obtained in prior work [53]. Compressive behavior of the N610/A composite remains approximately linear to failure at 900 ◦C. However, at 1100 ◦C, the compressive stress–strain curve consists of two nearly lin￾ear portions with a decrease in slope occurring as the stress Fig. 13. Fracture surfaces of a N610/M/A specimen from billet B14. (a) Multiple cracks initiate between the layers and (b) several short cracks (arrows) propagate into the 90◦ fiber layer and self-arrest