6 difference between edge dislocation and screw dislocation

 In this article, we are going to discuss the difference between Edge dislocation and Screw dislocation. Dislocation is one of the defects in the crystal structure which is also known as Line defects or One Dimensional defect. In this defect, the line of atoms moves from its original location.

Difference between Edge dislocation and Screw dislocation:

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Edge dislocation:

• Edge dislocation occurs due to the introduction or elimination of an extra row of atoms.
• Shear, Tensile and Compressive stress fields may be present in the Edge dislocation.
• In this dislocation, Burger’s vectors always perpendicular to the dislocation line.
• Region of lattice disturbance extends along an edge inside a crystal.
• This dislocation occurs due to climb and glide motion.
• There are two types of Edge dislocation, positive and negative.

Screw dislocation:

• Screw dislocation provides easy crystal growth because of additional unit cells and atoms can be added to the screw.
• Shear, Tensile and Compressive stress fields are absent in the Screw dislocation.
• In this dislocation, Burger’s vectors always parallel to the dislocation line.
• Region of lattice disturbance is in two separate planes and cross each other at right angles.
• This dislocation occurs only due to glide motion.
• Screw dislocation does not show any type like edge dislocation.