TY - GEN
T1 - Study on elasto-plastic behavior of different carbon types in carbon/carbon composites
AU - Ozcan, Soydan
AU - Tezcan, Jale
AU - Howe, Jane Y.
AU - Filip, Peter
PY - 2009
Y1 - 2009
N2 - The mechanical properties of carbon/carbon composites are sensitive to their crystallographic orientations and microstructures. Inelastic behavior can be characterized by studying their stress-strain behavior. Therefore, the aim of this work was to use nanoindentation methods to investigate the elasto-plastic behavior and related microstructures of PAN-fiber reinforced carbon matrix composites heat-treated at 2100°C. The microstructures were characterized using polarized light microscopy and high-resolution transmission electron microscopy. Nanoindentation tests were carried out to obtain loading-unloading cycles and elastic modulus data at different indentation depths using a three-faceted Berkovich-type diamond indenter. The residual displacement at complete unloading was correlated with the microstructure data to reveal the extent of the deformation of crystallites and graphene sheets. The pitch fiber and rough laminar pyrocarbon exhibited plastic behavior that can be attributed to the low shear resistance due to weak bonding between the well-organized graphene sheets. On the other hand, the PAN fiber, charred resin and isotropic pyrocarbon all exhibited almost full elasticity within the applied range of indentation depths.
AB - The mechanical properties of carbon/carbon composites are sensitive to their crystallographic orientations and microstructures. Inelastic behavior can be characterized by studying their stress-strain behavior. Therefore, the aim of this work was to use nanoindentation methods to investigate the elasto-plastic behavior and related microstructures of PAN-fiber reinforced carbon matrix composites heat-treated at 2100°C. The microstructures were characterized using polarized light microscopy and high-resolution transmission electron microscopy. Nanoindentation tests were carried out to obtain loading-unloading cycles and elastic modulus data at different indentation depths using a three-faceted Berkovich-type diamond indenter. The residual displacement at complete unloading was correlated with the microstructure data to reveal the extent of the deformation of crystallites and graphene sheets. The pitch fiber and rough laminar pyrocarbon exhibited plastic behavior that can be attributed to the low shear resistance due to weak bonding between the well-organized graphene sheets. On the other hand, the PAN fiber, charred resin and isotropic pyrocarbon all exhibited almost full elasticity within the applied range of indentation depths.
UR - http://www.scopus.com/inward/record.url?scp=62849120148&partnerID=8YFLogxK
U2 - 10.1002/9780470456361.ch14
DO - 10.1002/9780470456361.ch14
M3 - Conference contribution
AN - SCOPUS:62849120148
SN - 9780470344927
T3 - Ceramic Engineering and Science Proceedings
SP - 141
EP - 149
BT - Mechanical Properties and Processing of Ceramic Binary, Ternary, and Composite Systems - A Collection of Papers Presented at the 32nd International Conference on Advanced Ceramics and Composites
PB - American Ceramic Society
T2 - Mechanical Properties and Processing of Ceramic Binary, Ternary, and Composite Systems - 32nd International Conference on Advanced Ceramics and Composites
Y2 - 27 January 2008 through 1 February 2008
ER -