Accession Number : AD0704520

Title :   THE MOTION OF A DISLOCATION, ACTED ON BY A VISCOUS DRAG, THROUGH AN ARRAY OF DISCRETE OBSTACLES.

Descriptive Note : Technical rept.,

Corporate Author : HARVARD UNIV CAMBRIDGE MASS DIV OF ENGINEERING AND APPLIED PHYSICS

Personal Author(s) : Frost,H. J. ; Ashby,M. F.

Report Date : MAR 1970

Pagination or Media Count : 28

Abstract : A computer model was used to calculate the shape and average velocity of a dislocation acted on by a viscous drag, and moving through a field of point obstacles. As a special case, the operation of a Frank-Read source was computed also. At sufficiently low velocities (and stress levels) the behavior is governed entirely by the obstacle spacing and strength; conventional tensile probably falls in this regime. At sufficiently high velocities (and stress levels) the behavior is governed entirely by the viscous drag; explosive deformation falls in this regime. In between lies a wide range in which the two effects superimpose, each contributing measurably to the flow stress. (Author)

Descriptors :   (*RHEOLOGY, DISLOCATIONS), DRAG, MOTION, VELOCITY, STRESSES, DEFORMATION, EXPLOSION EFFECTS, DISPERSION HARDENING

Subject Categories : Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE