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Microstructural characterization of the Portevin–Le Chatelier band in an Al-Mg alloy by X-ray diffraction line profile analysis

Published online by Cambridge University Press:  29 February 2012

A. Sarkar ,
P. Mukherjee  and
P. Barat
A. Sarkar*
Affiliation:
Bhabha Atomic Research Centre, Mumbai 400085, India
P. Mukherjee
Affiliation:
Variable Energy Cyclotron Centre, Kolkata 700064, India
P. Barat
Affiliation:
Variable Energy Cyclotron Centre, Kolkata 700064, India
*
a)Author to whom correspondence should be addressed. Electronic mail: [email protected] and [email protected]
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Abstract

Al–2.5% Mg alloy exhibits the Portevin–Le Chatelier (PLC) effect at room temperature for a wide range of strain rates. Tensile test has been carried out on a flat Al–2.5% Mg alloy sample at a strain rate of 3.7×10−6 s−1. The strain rate was chosen so that the type C PLC band appears in the sample. X-ray diffraction profile has been recorded from the gauge length portion of the deformed sample to investigate the microstructure of the PLC band. Analysis revealed that the dislocation density is much higher within the band compared to the undeformed sample even at small strain. The PLC band in this alloy possesses an equal fraction of screw and edge dislocations.

Keywords

Portevin–Le Chatelier effectdislocationX-ray diffractiontension testAl alloy
Type
Technical Articles
Information
Powder Diffraction , Volume 25 , Issue 3 , September 2010 , pp. 270 - 273
Copyright
Copyright © Cambridge University Press 2010

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