FIZIKA A 8 (1999) 2 , 65-74

size 360kBsize 2097kB

EFFECT OF LOADING ON RECOVERY OF INTERNAL FRICTION OF Al-16 wt % Ag AND Al-16 wt % Ag - 0.28 wt % Fe ALLOYS

G. GRAISS and M. A. MAHMOUD

Physics Department, Faculty of Education, Ain-Shams University, Cairo, Egypt

Received 24 June 1999; Accepted 13 September 1999

The phenomenon of internal-friction recovery of Al-16 wt % Ag and Al-16 wt % Ag - 0.28 wt % Fe alloys is studied after cold-working the samples in uniaxial tension using the free decay method. The wire samples are investigated for internal friction recovery while they were loaded, within the elastic limit, by different loads at different testing temperatures. It is found that by increasing the temporary loading, the rate of recovery decreases. TEM investigations confirmed that the addition of Fe to Al-Ag alloy accelerates the formation and coarsening of Guinier-Preston zones. The results are explained on the basis of dislocation damping adopting the Granato-Lücke model for recovery of internal friction.

PACS numbers: 61.72.Hh, 62.40.+i
UDC 531.785.5
Keywords: internal friction recovery, Al-Ag and Al-Ag-Fe alloys, cold-working in uniaxial tension, free decay method, wire samples, different testing temperatures, Granato-Lücke model for recovery of internal friction
Copyright by The Croatian Physical Society
For problems or questions please contact fizika@fizika.hfd.hr