Engineering Fracture Mechanics

The course covers the basic aspects of Engineering Fracture Mechanics. Spectacular failures that triggered the birth of fracture mechanics, Modes of loading, Classification as LEFM and EPFM, Crack growth and fracture mechanisms, Energy release rate, Resistance, Griffith Theory of fracture, Extension of Griffith Theory by Irwin and Orowan, R-Curve, Pop-in phenomena, Crack branching. Necessary and sufficient conditions for fracture, Stress and Displacement fields in the very near and near-tip fields, Westergaard, Williams and Generalised Westergaard solutions, Influence of the T-stress and higher order terms, Role of photoelasticity on the development of stress field equations in fracture mechanics, Equivalence between SIF and G, Various methods for evaluating Stress Intensity Factors, Modeling plastic zone at the crack-tip, Irwin and Dugdale models, Fracture toughness testing,Fedderson TMs residual strength diagram, Paris law, J-integral, HRR field, Mixed-mode fracture, Crack arrest methodologies.INTENDED AUDIENCE : Students in Engineering Colleges and working professionals in similar areasPRE-REQUISITES : Basic course on Strength of Materials. Course on Theory of Elasticity desirableINDUSTRY SUPPORT : HAL, Honeywell, GE, GM, NAL, DMRL, DRDO, BEML, Mahindra&Mahindra, Tata Motors, L&T, VSSC, Defense and Atomic energy Laboratories

Week 1 : EFM Course outline and Spectacular FailuresWeek 2 : Introduction to LEFM and EPFM, Fatigue Crack Growth ModelWeek 3 : Crack Growth and Fracture Mechanisms, Griffith TMs Theory of FractureWeek 4 : Energy Release RateWeek 5 : Review of Theory of ElasticityWeek 6 : Westergaard Solution for Stress and Displacements for Mode I, Relationship between K and GWeek 7 : Introduction to multi parameter stress field for Mode I, Mode II and Mixed ModesWeek 8 : SIF for Various GeometriesWeek 9 : Modeling Plastic Deformation, Irwin TMs model, Dugdale ModelWeek 10 : Fracture Toughness Testing, Paris Law and Sigmoidal curveWeek 11 : Crack Closure, Crack Growth Models, J-IntegralWeek 12 : Failure Assessment Diagram, Mixed Mode Fracture, Crack Arrest and Repair Methodologies