Accession Number : AD0760145

Title :   Internal Friction During Repeated Discontinuous Yielding of Metals,

Corporate Author : TECHNION - ISRAEL INST OF TECH HAIFA DEPT OF MATERIALS ENGINEERING

Personal Author(s) : Baruch,J. ; Bodner,Sol R.

Report Date : FEB 1973

Pagination or Media Count : 23

Abstract : Internal friction measurements were made on three FCC alloys, alpha-brass and 2024 and 6063 aluminum, coincident with repeated discontinuous yielding of the specimens (Portevin-Le Chatelier effect). A torsional pendulum arrangement was used to obtain low amplitude, low frequency (10-30 Hz) damping values while the specimens were plastically deforming under 'dead weight' loading. The internal friction was found to be amplitude independent and to vary linearly with strain rate. The linear dependence of internal friction on strain rate was obtained during the full course of a test and particularly during each individual strain jump at constant stress. These results indicate that the mobile dislocation density is primarily responsible for internal friction in the low amplitude, low frequency range. (Author, modified-PL)

Descriptors :   (*BRASS, INTERNAL FRICTION), (*ALUMINUM ALLOYS, INTERNAL FRICTION), LOADS(FORCES), DEFORMATION, STRAIN HARDENING, STRESSES, PLASTIC PROPERTIES, CREEP, ISRAEL

Subject Categories : Metallurgy and Metallography
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE