Evaluation of Piezoresistivity in Heat Treated 5A06 Al-Mg alloy Due to Applied Stress Using Eddy Current Method

Abstract:

Eddy current method can be used for non-destructive assessment of residual stress. In order to relate electrical conductivity change to the residual stresses in the welded joints, piezoresistivity of 5A06 has been investigated using samples heat treated at 2500C and 4000C. These samples represent weld zones with different thermal exposure. A directional eddy current probe with a Hall Effect sensor was used to evaluate stress coefficient of electrical conductivity due to applied uniaxial tensile load on the samples. The electromagnetic forward model was solved using FEM package and linear conductivity inversion was formulated to express probe output in terms of electrical conductivity. The piezoresistivity coefficients of samples, calculated from the derivative of stress-conductivity relation, were compared. The results indicate that coefficients vary inversely with annealing temperature.

• Periodical: Advanced Materials Research (Volume 548)
• Pages: 377-381
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.548.377
• Online since: July 2012
• Authors: Shakoor Abdul, Zheng Gan Zhou
• Keywords: Al-Mg Alloy, Eddy Current, Piezoresistivity, Welded Joint

References

[1] Z. Barsoum and I. Barsoum. Residual stress effects on fatigue life of welded structures using LEFM. Eng. Fail. Anal. Vol. 16 (2009), pp.449-467.

DOI: 10.1016/j.engfailanal.2008.06.017

[2] C. Liljedahl, J. Broud, O. Zanellato, J. Lin, M.L. Tan. Weld residual stress effects on fatigue crack growth behavior of aluminum alloy 2024-T351. Int. J. Fatigue. Vol. 31 (2009), pp.1081-1088.

DOI: 10.1016/j.ijfatigue.2008.05.008

[3] Y. Shen, C. Lee, C.C.H. Lo, N. Nakagawa and A.M. Frishman. Conductivity profile determination by eddy current for shot peened superalloy surfaces towards residual stress assessment. J. Appl. Phys. Vol. 101 (2007), p.014907.

DOI: 10.1063/1.2403970

[4] H. Chang, F. Schoenig and J. Soules. Nondestructive residual stress measurement using eddy current. Proceedings of ICSP-6 (1996), pp.356-384.

[5] B.A. Abu-Nabah, F. Yu, W.T. Hassan, M.P. Blodgett and P.B. Nagy. Eddy current residual stress profiling in surface treated engine alloys. Nondestr. Test. Eval. Vol. 24 (2009), pp.209-232.

DOI: 10.1080/10589750802245280

[6] F. Yu and P.B. Nagy. Dynamic piezoresistivity calibration for eddy current nondestructive residual stress measurement. Nondestr. Test. Eval. Vol. 24 (2005), pp.143-151.

DOI: 10.1007/s10921-005-8783-9

[7] M. Morozov, G.Y. Tian and P.J. Withers. Noncontact evaluation of the dependency of electrical conductivity on stress for various Al alloys as a function of deformation and annealing. J. App. Phys. Vol. 108 (2010), p.024909.

DOI: 10.1063/1.3456996

[8] D. Grady and M. Ginsberg. Piezoresistive effect in ytterbium stress transducers. J. App. Phys. Vol. 48 (1997), pp.2179-2181.

[9] M. Popovic and E. Romhanji. Characterization of microstructural changes in an Al-6. 8 wt% Mg alloy by electrical resistivity measurements. Mater. Sci. Eng., A. Vol. 492 (2008), pp.460-467.

DOI: 10.1016/j.msea.2008.04.001

[10] A. Shakoor and Z. Zhenggan. Investigation of 3D anisotropic electrical conductivity in TIG welded 5A06 Al alloy using eddy currents. J. Mater. Process. Technol. Vol. 211(11) (2011), pp.1736-1741.

DOI: 10.1016/j.jmatprotec.2011.05.011

[11] T.G. Santos, P. Vilaca and R.M. Miranda. Electrical conductivity field analysis for evaluation of FSW joints in AA6013 and AA7075 alloys. J. Mater. Process. Technol. Vol. 211 (2) (2011), pp.174-180.

DOI: 10.1016/j.jmatprotec.2010.08.030

[12] O. Hatamleh, I.V. Rivero and A. Maredia. Residual stresses in friction stir welded 2195 and 7075 aluminum alloys. Metall. Mater. Trans. A. Vol. 39 (2008), pp.2867-2874.

DOI: 10.1007/s11661-008-9657-4

[13] P. Staron, M. Kocak and S. Williams. Residual stress in friction stir welded Al sheets. Appl. Phys. A. Vol. (74) (2002), pp. S1161-S1162.

DOI: 10.1007/s003390201830