Dislocations and Strengthening Mechanisms

A set of flashcards covering significant concepts related to dislocations, their movement, and strengthening mechanisms in materials.

Dislocation

A linear crystalline defect that contributes to plastic deformation in materials.

Edge Dislocation

A dislocation characterized by a half-plane of atoms that causes distortion in the lattice structure.

Screw Dislocation

A dislocation that results from shear distortion and has a helical ramp structure.

Plastic Deformation

The permanent deformation of a material that occurs when dislocations move under applied stress.

Slip Plane

The crystallographic plane along which dislocation motion occurs during plastic deformation.

Slip Systems

The combination of slip planes and slip directions where dislocations move most easily.

Dislocation Density

The number of dislocations within a material, usually expressed per unit area or volume.

Strain Hardening

The process in which a ductile metal becomes stronger as it is plastically deformed, often called work hardening.

Recovery

The process through which some of the stored internal strain energy is relieved at elevated temperatures.

Recrystallization

Formation of new strain-free grains within a metal that have low dislocation density after heat treatment.

Grain Growth

The process whereby strain-free grains grow larger at high temperatures, reducing total energy associated with grain boundaries.

Slip Direction

The direction along which dislocations move, typically the most closely packed direction in the crystal structure.

Modified Hall-Petch Equation

An equation describing that yield strength increases with decreasing grain size, though with limits.