1. (a) (b) Explain the difference between Griffith and Irwin's approach to determine the critical stress in cracks for fast fracture in engineering materials. Why are dislocations necessary for explaining the plasticity typically seen for crystalline materials?
1. (a) (b) Explain the difference between Griffith and Irwin's approach to determine the critical stress in cracks for fast fracture in engineering materials. Why are dislocations necessary for explaining the plasticity typically seen for crystalline materials?
Related questions
Question
Transcribed Image Text:1. (a)
(b)
(c)
Explain the difference between Griffith and Irwin's approach
to determine the critical stress in cracks for fast fracture in
engineering materials.
Why are dislocations necessary for explaining the plasticity
typically seen for crystalline materials?
A thin sheet of aluminium alloy of width 200mm and 200
mm long with an internal crack of 80mm is subjected to an
applied stress of 130MPa perpendicular to the crack plane.
Apply Irwin's Approach for plasticity correction to find the
plastic zone size of the crack tip, and hence find the stress
intensity factor at the crack tip (for 2 iterations).
The yield strength of aluminium alloy is 380MPa.
The stress intensity factor K₁ is given by
K₁=Y σ (na)¹/²
where a is the crack length and is the applied stress.
Note that the geometric correction factor graph and the
relevant equations are provided in the Appendix.
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
Step by step
Solved in 4 steps with 1 images
