论文信息 - Fracture toughness anisotropy of a pyrolytic carbon

Fracture toughness anisotropy of a pyrolytic carbon

The anisotropic flexural strengths, static Young's moduli and the corresponding fracture toughnesses were measured for the three orthogonal fracture surface orientations,Sca (interlaminar cleavage),Sba andSab (layer rupture across and along the layers, respectively), of an as deposited substrate-nucleated pyrolytic carbon. BothSca delamination andSab along-layer rupture produced smooth fracture surfaces with meanKlc values (MPam1/2) of 0.53 forSca and 0.93 forSab, independent of notch length. A different type of behaviour was observed forSbc across-layer fracture. Delamination cracking during failure resulted in rough fracture surfaces, crack arrests, and high apparent toughness values dependent on sample size and crack length. The nature of this induced delamination toughening is discussed.

R. C. Bradt | R. Bradt | M. Sakai | D. B. Fischbach | M. Sakai

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