Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-14T15:17:43.420Z Has data issue: false hasContentIssue false
  • English
  • Français

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]
Get access Rights & Permissions [Opens in a new window]

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

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Ait-Amokhtar, H., Fressengeas, C., and Boudrahem, S. (2008). “The dynamics of Portevin–Le Chatelier bands in an Al-Mg alloy from infrared thermography,” Mater. Sci. Eng., A MSAPE3 488, 540–546.10.1016/j.msea.2007.11.075CrossRefGoogle Scholar
Banerjee, S. and Naik, U. M. (1996). “Plastic instability in an omega forming Ti-15% Mo alloy,” Acta Mater. ACMAFD 44, 3667–3677.10.1016/1359-6454(96)00012-2CrossRefGoogle Scholar
Borbély, A. and Groma, I. (2001). “Variance method for the evaluation of particle size and dislocation density from X-ray Bragg peaks,” Appl. Phys. Lett. APPLAB 79, 1772–1774.10.1063/1.1404134CrossRefGoogle Scholar
Chihab, K., Estrin, Y., Kubin, L. P., and Vergnol, J. (1987). “The kinetics of the Portevin–Le Chatelier bands in an Al–5 at. % Mg alloy,” Scr. Metall. SCRMBU 21, 203–208.10.1016/0036-9748(87)90435-2CrossRefGoogle Scholar
Dong, Y. H. and Scardi, P. (2000). “MARQX: A new program for whole-powder-pattern fitting,” J. Appl. Crystallogr. JACGAR 33, 184–189.10.1107/S002188989901434XCrossRefGoogle Scholar
Groma, I. (1998). “X-ray line broadening due to an inhomogeneous dislocation distribution,” Phys. Rev. B PLRBAQ 57, 7535–7542.10.1103/PhysRevB.57.7535CrossRefGoogle Scholar
Groma, I., Ungar, T., and Wilkens, M. (1988). “Asymmetric X-ray line broadening of plastically deformed crystals. I. Theory,” J. Appl. Crystallogr. JACGAR 21, 47–54.10.1107/S0021889887009178CrossRefGoogle Scholar
Halim, H., Wilkinson, D. S., and Niewczas, M. (2007). “The Portevin–Le Chatelier (PLC) effect and shear band formation in an AA5754 alloy,” Acta Mater. ACMAFD 55, 4151–4160.10.1016/j.actamat.2007.03.007CrossRefGoogle Scholar
Hearmon, R. F. S. (1979). “The Elastic Constants of Crystals and Other Anisotropic Materials,” Landolt-Börnstein Tables, in Landolt-Börnstein Tables, Group III, Pt. 11, edited by Hellwege, K. H. and Hellwege, A. M. (Springer-Verlag, Berlin), pp. 1–244.Google Scholar
Hogg, S. C., Palmer, I. G., Thomas, L. G., and Grant, P. S. (2007). “Processing, microstructure and property aspects of a spraycast Al-Mg-Li-Zr alloy,” Acta Mater. ACMAFD 55, 1885–1894.10.1016/j.actamat.2006.10.057CrossRefGoogle Scholar
Kubin, L. P. and Estrin, Y. (1985). “The Portevin–Le Chatelier effect in deformation with constant stress rate,” Acta Metall. AMETAR 33, 397–407.10.1016/0001-6160(85)90082-3CrossRefGoogle Scholar
Kubin, L. P., Fressengeas, C., and Ananthakrishna, G. (2002). “Collective behaviour of dislocations in plasticity,” in Dislocations in Solids, edited by Nabarro, F. R. N. and Duesbery, M. S. (Elsevier, Amsterdam), Vol. 11, pp. 101–192.10.1016/S1572-4859(02)80008-0Google Scholar
McCormigk, P. G. (1972). “A model for the Portevin–Le Chatelier effect in substitutional alloys,” Acta Metall. AMETAR 20, 351–354.10.1016/0001-6160(72)90028-4CrossRefGoogle Scholar
Mittemeijer, E. J. and Scardi, P. (2004). Diffraction Analysis of the Microstructure of Materials (Springer, Berlin).CrossRefGoogle Scholar
Picu, R. C. and Zhang, D. (2004). “Atomistic study of pipe diffusion in Al-Mg alloys,” Acta Mater. ACMAFD 52, 161–171.10.1016/j.actamat.2003.09.002CrossRefGoogle Scholar
Ranc, N. and Wagner, D. (2005). “Some aspects of Portevin–Le Chatelier plastic instabilities investigated by infrared pyrometry,” Mater. Sci. Eng., A MSAPE3 394, 87–95.10.1016/j.msea.2004.11.042CrossRefGoogle Scholar
Rizzi, E. and Hahner, P. (2004). “On the Portevin–Le Chatelier effect: Theoretical modeling- and numerical results,” Int. J. Plast. IJPLER 20, 121–165.10.1016/S0749-6419(03)00035-4CrossRefGoogle Scholar
Shabadi, R., Kumar, S., Roven, H. J., and Dwarakadasa, E. S. (2004). “Characterisation of PLC band parameters using laser speckle technique,” Mater. Sci. Eng., A MSAPE3 364, 140–150.10.1016/j.msea.2003.08.013CrossRefGoogle Scholar
Snyder, R. L., Fiala, J., and Bunge, H. J. (1999). Defect and Microstructure Analysis by Diffraction (Oxford University Press, Oxford).Google Scholar
Stokes, A. R. (1948). “A numerical Fourier-analysis method for the correction of widths and shapes of lines on x-ray powder photographs,” Proc. Phys. Soc. London PPSOAU 61, 382–391.10.1088/0959-5309/61/4/311CrossRefGoogle Scholar
Ungár, T., Dragomir, I., Révész, A., and Borbély, A. (1999). “The contrast factors of dislocations in cubic crystals: The dislocation model of strain anisotropy in practice,” J. Appl. Crystallogr. JACGAR 32, 992–1002.10.1107/S0021889899009334CrossRefGoogle Scholar
Ungára, T., Ott, S., Sanders, P. G., Borbely, A., and Weertman, J. R. (1998). “Dislocations, grain size and planar faults in nanostructured copper determined by high resolution X-ray diffraction and a new procedure of peak profile analysis,” Acta Mater. ACMAFD 46, 3693–3699.10.1016/S1359-6454(98)00001-9CrossRefGoogle Scholar
van den Beukel, A. (1975). “Theory of the effect of dynamic strain aging on mechanical properties,” Phys. Status Solidi A PSSABA 30, 197–206.10.1002/pssa.2210300120CrossRefGoogle Scholar
Vannarat, S., Sluiter, H. F. M., and Kawazoe, Y. (2001). “First-principles study of solute-dislocation interaction in aluminum-rich alloys,” Phys. Rev. B PLRBAQ 64, 224203(1-8).10.1103/PhysRevB.64.224203CrossRefGoogle Scholar
Warren, B. E. (1969). X-Ray Diffraction (Addison-Wesley, Reading, MA).Google Scholar
Williamson, G. K. and Hall, W. H. (1953). “X-ray line broadening from filed aluminium and wolfram,” Acta Metall. AMETAR 1, 22–31.10.1016/0001-6160(53)90006-6CrossRefGoogle Scholar