Question

NiAl is an intermetallic compound which has the CsCl-type crystal structure, which is shown below. The Bravais lattice is simple cubic, with Al atoms at the corners of a cube, and one Ni atom at the center. Slip occurs on {110} (001). The Burgers vector usually is the shortest distance between identical atom positions, and for this system this is the case. What is the magnitude of the Burgers vector for NiAl? Give your answer as a function of the lattice parameter a.

Answer 1

Burger vector is usually the shortest distance between identical atom position in the crystal system. Now for bcc lattice system magnitude of burger vector || b|| = (a/2)*(h^2 + k^2 + l^2) ^1/2

The given system NiAl is bcc type and [110]<001> slip system. The burger vector b would be then calculated by sqrt (1) times a/2. Sqrt (1) because dislocation would slip in this preferred slip system through the crystal. If the slip system changes, the Burger's vector must change too.