Key Features: 

• Formation of Crystal Defects: Dislocations develop by the action of applied stress, alloying, and imperfections, which influence the deformation of metals under load. 
• Impact on Strength: Hardness and ductility are affected by dislocation movement. Strengthening or weakening of the material is a consequence of controlled dislocation motion. 
• Role in Metalworking: Interventions such as work hardening and annealing use dislocations to alter mechanical properties. The importance of dislocations in industries that require a predictable performance of materials is paramount. 

Dislocations are thus heavily implicated in influencing the mechanical behavior of metals. This essentially underpins metallurgy and materials engineering in designing strong and durable components. The advancement of dislocation control technologies has led to the birth of high-performance alloys and better manufacturing methods.