Internal Friction and Young's Modulus of 9Al2O3 2B2O3 Whisker Reinforced Aluminum Matrix Composite


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Anelastic behavior of a 9Al2O3·2B2O3 (AlBw) whisker reinforced aluminum composite has been examined through the measurements of the dynamic Young’s modulus and internal friction over a temperature range of 25 to 500°C at frequencies of 0.01, 0.05 and 0.1 Hz. A standard servo-hydraulic mechanical testing machine equipped with an infrared lamp heater was employed, but the dynamic measurement system therein was especially designed by assembling a scanning laser extensometer and a frequency response analyzer for detecting the amplitude and phase lag of strain in response to a sinusoidal time-varying stress. Two peaks of internal friction were observed over the ranges 100 to 250°C (LT peak) and 250 to 400°C (HT peak), together with marked decreases in the dynamic Young's modulus in the same temperature ranges. From a quantitative analysis of the experimental data, it is concluded that the HT peak phenomenon is due to grain-boundary relaxation, whereas the LT peak phenomenon is ascribable to the relaxation caused by stress-directed interfacial diffusion of Al atoms along the whisker-matrix interface.



Materials Science Forum (Volumes 539-543)

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Edited by:

T. Chandra, K. Tsuzaki, M. Militzer , C. Ravindran




C. S. Kang et al., "Internal Friction and Young's Modulus of 9Al2O3 2B2O3 Whisker Reinforced Aluminum Matrix Composite", Materials Science Forum, Vols. 539-543, pp. 997-1003, 2007

Online since:

March 2007




[1] C. Zener, Elasticity and Anelasticity of Metals, (Univ. of Chicago Press, Chicago, Illinois, 1948).

[2] A.S. Nowick and B.S. Berry, Anelastic Relaxation in Crystalline Solids, (Academic Press, New York, 1972).

[3] C. S Kang, K. Maeda, K. -J Wang and K. Wakashima, Acta mater. Vol. 46(1998), p.1209.

[4] C. Zener, Phys. Rev. Vol. 60 (1941), p.906.

[5] Y, -S. eˆK , Phys. Rev. Vol. 72(1947), p.41.

[6] Y, -S. eˆK , Phys. Rev. Vol. 71(1947), p.533.

[7] J. N. Cordea and J. W. Spretnak, Trans. TMS AIME Vol. 236(1966), p.1685.

[8] M. Okabe, T. Mori and T. Mura, Phil. Mag. Vol. A44(1981), p.1.