2134/5623
Houzheng Wu
Houzheng
Wu
Steve G. Roberts
Steve G.
Roberts
Brian Derby
Brian
Derby
Ductile deformation in alumina/silicon carbide nanocomposites
Loughborough University
2009
untagged
Information and Computing Sciences not elsewhere classified
2009-12-08 15:11:06
Journal contribution
https://repository.lboro.ac.uk/articles/journal_contribution/Ductile_deformation_in_alumina_silicon_carbide_nanocomposites/9404138
A transmission electron microscope study on cross sections obtained from ground and polished
surfaces has revealed that ductile deformation is dominated by dislocations in alumina/silicon carbide
nanocomposites containing 1, 5 and 10 vol% silicon carbide particles, and by twinning in unreinforced
alumina. The dispersed silicon carbide particles in alumina/silicon carbide nanocomposites restrict the
motion of dislocations. A dislocation pinning model is used to compare the possible mechanisms of
deformation in alumina and the nanocomposites. Cr-fluorescence piezospectroscopy has been used to
characterise the residual stress levels in the materials studied. The measured broadening of the
Al2O3/Cr3+ fluorescence peak indicates a dislocation density of 7.3 - 9.7 x 1016 m-2 under the
indentations in the nanocomposites, whilst the beneath indentations in alumina is 1-2 orders of
magnitude smaller.