Edge Dislocation: Line and Burgers Vector Angle
An edge dislocation is a fundamental type of crystallographic defect. It can be visualized as an extra half-plane of atoms inserted into a crystal structure.
Line Vector Definition
The line vector, typically represented as `l`, indicates the direction along which the dislocation exists within the crystal lattice.
Burgers Vector Definition
The Burgers vector, denoted by `b`, quantifies the lattice distortion. It is determined by tracing a closed loop around the dislocation and measuring the closure failure in a perfect crystal.
Vector Orientation in Edge Dislocations
A key characteristic of an edge dislocation is the geometric relationship between its line vector and its Burgers vector. In an edge dislocation, the Burgers vector is always perpendicular to the direction of the dislocation line.
Determining the Angle
Since the Burgers vector `b` is perpendicular to the line vector `l` in an edge dislocation, the angle between them is necessarily $90^\circ$.
Angle = $90^\circ$
Important Questions from Defects Dislocation Stress Field Burgers Vector
- Which one of the following dislocation dissociation reactions is feasible in face-centered cubic metals?
- With reference to edge and screw dislocations, which of the following statements is/are CORRECT?
The Burger's vector of a dislocation in a cubic crystal (with lattice parameter a) is $\frac{a}{2}[110]$ and dislocation line is along $[112]$ direction. The angle (in degrees) between the dislocation line and its Burger's vector is _________
- A plastically deformed metal crystal at low temperature exhibits wavy slip line pattern due to
- The c/a ratio of Zn (hcp) is 1.856. Slip at room temperature occurs most easily on which of the following slip systems in Zn:
Note: In hcp metals, the ideal c/a ratio is 1.633.
