Fracture surface roughness and toughness of Al2O3-platelet reinforced glass matrix composites

The correlation between fracture surface roughness and fracture toughness o f alumina platelet reinforced borosilicate glass matrix composites was inve stigated. With increasing volume fraction of platelets both fracture toughn ess and fracture surface roughness increase. The fracture roughness paramet er Ra was determined by the profilometric technique. A linear correlation w as found between the fracture toughness and the Ra values of the composites . Scanning electron microscopy observation of fracture surfaces confirmed t hat surface roughness is related to a crack deflection process. Crack defle ction is thus one of the toughening mechanisms acting in these composites. (C) 2001 Elsevier Science Ltd. All rights reserved.