This is a continuation of the course “Defects in Crystalline Solids (Part-I). In this part of the course, students should be able to Understand dislocations with respect to particular crystal system (eg. FCC, BCC, HCP and also superlattices)Relate dislocation to the plastic properties of the material, particularly, strengthening mechanisms.
Week 1 : Dislocations in FCC; Partial Dislocations; Thompson’s Tetrahedron; Cottrell Lock; Lomer-Cottrell Lock; Intersection of extended dislocations
Week 2 : Dislocations in BCC, HCP and other systems; Dislocations in Superlattices; Kear-Wilsdorf Locks
Week 3 : Interaction of dislocations with vacancies and its effect on plasticity; Strengthening mechanisms due to interaction of dislocations with interfaces, precipitates, inclusions; Dislocation generation mechanisms
Week 4 : Dislocations and Grain boundaries; Read-Shockley model for Low angle grain boundaries; A modified model for LAGB energy; Energy of LAGBs from dislocation model; CSL boundaries and secondary dislocations; Geometrically necessary dislocations (GNDs) and Statistically Stored Dislocations (SSDs).