Accession Number : ADA258913


Title :   Computational and Experimental Investigation into Fracture of Brittle Fiber - Brittle Matrix Composite Systems


Descriptive Note : Master's thesis


Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING


Personal Author(s) : Solti, James P


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a258913.pdf


Report Date : Dec 1992


Pagination or Media Count : 160


Abstract : Experimental and computational analyses provided an improved understanding of quasi-static fracture in model composite systems. Constant displacement compression tests using borosilicate glass double cleavage drilled compression test templates provided qualitative assessments of localized toughening for crack growth near cylindrical inclusions. Large crack-tip stress fields induced interfacial slip and separation prior to arrival of the main crack. Debonding and the proliferation of secondary matrix cracks characterized the role of bridging fibers along weak interfaces. Strong residual normal compressive interfacial stresses diminished the influence of crack-tip stresses; however, slip was still observed. VHS tape and computer enhanced photos record a history of crack propagation and interfacial slip. Experimental data was used to validate a fully three-dimensional computational code capable of analyzing fracture near and around cylindrical inclusions. Consistent variations in the shape of the crack periphery renders confidence in the elasticity solution.


Descriptors :   *FIBERS , *COMPOSITE MATERIALS , *MATRIX MATERIALS , *BRITTLENESS , *FRACTURE(MECHANICS) , TEST AND EVALUATION , COMPRESSION , EXPERIMENTAL DATA , MODELS , SECONDARY , DISPLACEMENT , THESES , RESIDUALS , CRACK PROPAGATION , THREE DIMENSIONAL , BOUNDARIES , MECHANICS , INCLUSIONS , VARIATIONS , GLASS , TOUGHNESS , CLEAVAGE , STATICS , RECORDS , SEPARATION , TAPES , TEMPLATES , HISTORY , SHAPE , CRACKS , INTERFACES , COMPUTERS , COMPUTATIONS , STRESSES , PROPAGATION


Subject Categories : Ceramics, Refractories and Glass
      Laminates and Composite Materials
      Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE