Length scale effects in plastic deformation, restrictions on plastic deformation, and realistic simulation of fracture behavior are critical for future engineering design and reliability. Plastic deformation is a manifestation of the accumulated motion of the individual dislocations. Lower-scale simulations using DDP capture the mechanics of individual dislocations, resulting in natural length scale effects in plastic deformation, and are capable of simulating boundary conditions on plastic deformation and simulation of realistic fracture. Currently computational cost for DDP is prohibitive for realistic engineering problems. To enable simulation of the length scale phenomena involving plastic deformation at small length scales, numerical implementations of Gurtin strain gradient plasticity are developed here. The numerical implementations developed for Gurtins theory are used for simulation of problem of constrained shear and mode I fracture. Limitations of the numerical method are discussed while discussing the specific simulation of problems. The predictions from Gurtins theory simulated with energetic hardening only are compared with results in literature with other gradient theories for similar situation. The conclusions from this research and recommendations for future work to address the open challenges of engineering simulations for constrained plastic deformation, length scale effects, and fracture are also discussed.
Nath, Prateek,
"Implementation and Application ofGurtin Strain Gradient Viscoplasticity"
(2011).
Mechanics of Solids Theses and Dissertations.
Brown Digital Repository. Brown University Library.
https://doi.org/10.7301/Z0WW7FX7
