IN a recent letter in Nature, Amelinckx 1 has given evidence for the existence of screw dislocations in mica. He observed a step, 140 A. high, which terminated on the surface : the point of ...

For nearly a century, scientists have understood how crystalline materials—such as metals and semiconductors—bend without breaking. Their secret lies in tiny, line-like defects called dislocations, ...

· The Mixed dislocations is the most general type of unit dislocation and has an arbitrary angle between its line vector and Burgers vector. b is a constant of the dislocation. · The dislocation line ...

· For the Screw dislocation, the Burgers vector and the Line vector are parallel. · A straight screw dislocation creates a helical configuration for the planes normal to the dislocation line. The ...