NASA STI Repository (National Aeronautics and Space Administration) · 1990 · 14 citations · 16 references
Open access
Natural SciencesMaterials EngineeringMaterials ScienceCeramic MaterialsCeramicsMechanical Behavior Of MaterialsFracture MechanicsFracture PropagationFracture ResistanceFracture ToughnessGlass MaterialsIndentation PropertiesCeramic Fracture ToughnessCrack GrowthCrack Growth MeasurementCrack Growth RateDynamic LoadingDynamic Mechanical LoadingIndentation Fracture ToughnessIndentation Mechanics
The fracture toughness and crack growth parameters of Zerodur, a low expansion glass ceramic material, were determined. The fracture toughness was determined using indentation techniques and was found to be 0.9 MPa x m(sup 1/2). The crack growth parameters were determined using indented biaxial specimens subjected to static and dynamic loading in an aqueous environment. The crack growth parameters n and 1n(B) were found to be 30.7 and -6.837, respectively. The crack growth parameters were also determined using indented biaxial specimens subjected to dynamic loading in an ambient 50 percent relative humidity environment. The crack growth parameters n and 1n(B) at 50 percent relative humidity were found to be 59.3 and -17.51, respectively.
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