Mechanical Failure: temperature, stress, cyclic and loading effect
ISSUES TO ADDRESS...
- How do cracks that lead to failure form?
- How is fracture resistance quantified? How do the fracture
resistances of the different material classes compare?
- How do we estimate the stress to fracture?
- How do loading rate, loading history, and temperature
affect the failure behavior of materials?
- Fracture, Fatigue and Creep
- Fracture mechanisms: Ductile vs Brittle Failure
- Stress-Strain Behavior versus Temperature
- Charpy Impact Testing
- Charpy V-Notch Impact Data: Energy vs Temperature
- Famous example failures: Liberty ships
- Ductile Fracture: distinctive features on macro and micro levels
- Fracture Surface under Tensile and Shear load
- Brittle Fracture Surface
- Brittleness of Ceramics
- Porosity and Temperature Effects in Ceramics
- Nucleation and Propagation Of Cracks in Ceramics
- Crazing during Fracture of Thermoplastic Polymers
- Ideal versus Real Behavior
- Flaws are Stress Concentrators!
- Concentration of Stress at Crack Tip
- Modes of Fracture which Operate on Cracks
- Griffith’s Criteria for Fracture and Failure
- Fatigue: Failure from cyclic stress
- S-N Curves Failure
- Fatigue Behavior of Polymers
- Fatigue Mechanisms
- Improving Fatigue Life
- Anelastic Effects
- Creep Failure and Secondary Creep
- Creep RECOVERY and Vacancy-assisted Climb
- Major recover mechanism is non-conservative climb
- Design Examples, Design Strategy, Case Studies