Crack growth resistance of Cr3C2/Al2O3 composites

Abstract The crack resistance of Cr 3 C 2 /Al 2 O 3 composites was investigated. The indentation/strength technique was used to determine the R-curve behaviors. The small (2 μm) Cr 3 C 2 particles were found to have a better toughening effect than that of large (7 μm) Cr 3 C 2 particles in Cr 3 C 2 /Al 2 O 3 composites. The R-curve behaviors in Cr 3 C 2 /Al 2 O 3 composites could be attributed to the mechanisms of crack-deflection and crack-branching. Materials exhibiting R-curve behavior also had narrower strength distribution and larger Weibull modulus than those of Griffith materials.