Accession Number : AD0645213

Title :   THE MICROSTRAIN REGION IN HIGH PURITY REFRACTORY METALS.

Descriptive Note : Quarterly progress rept. no. 3, 1 Sep-30 Nov 66,

Corporate Author : FRANKLIN INST RESEARCH LABS PHILADELPHIA PA

Personal Author(s) : Prekel,Heinrich L. ; Lawley,Alan ; Conrad,Hans

Report Date : 30 NOV 1966

Pagination or Media Count : 21

Abstract : Dislocation velocity measurements at room temperature on molybdenum single crystals by the etch-pitting method are described. It is shown that the stress dependence of the dislocation velocity obeys the relationship v = (tan/tan sub o) to the mth power with m about 6.4 and tan sub o about 5.5 Kg mm to the minus 2nd power. It is also shown that this relationship can be derived directly from thermal activation theory and that the results support the thermally activated overcoming of the Peierls hills as the rate controlling process in the plastic deformation of molybdenum. (Author)

Descriptors :   (*REFRACTORY METALS, STRAIN(MECHANICS)), (*MOLYBDENUM, DISLOCATIONS), SINGLE CRYSTALS, STRESSES, VELOCITY, HEAT OF ACTIVATION, THEORY, DEFORMATION

Subject Categories : Properties of Metals and Alloys
      Crystallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE