Nanocrystalline Mg-3%Al Alloy: its Synthesis and Investigation of its Tensile Behavior

The tensile properties of Mg-3%Al nanocrystalline alloys were investigated at different test environment. Bulk nanocrystalline samples of these alloy was successfully prepared by mechanical alloying (MA) followed by cold compaction, sintering, and hot extrusion process. The crystal size of the consolidated milled sample was calculated by X-Ray line profile analysis. The deformation mechanism and microstructural characteristic at different test condition was discussed extensively. At room temperature, relatively lower value of activation volume (AV) and higher value of strain rate sensitivity (SRS) suggests that new rate controlling mechanism accommodating plastic flow in the present nanocrystalline sample. The deformation behavior and the microstructural character of the present samples were discussed in details.

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References:
[1] L. Lu, K. Raviprasad, and M. O. Lai, "Nanostructured Mg-5%Al-x%Nd
alloys, Mater. Sci. Eng. A, vol. 368, pp. 117-125, 2004.
[2] C. W. Su, B. W. Chua, L. Lu, and M. O. Lai, "Properties of severe
plastically deformed Mg alloys", Mater. Sci. Eng. A, vol. 402, pp. 163-
169, 2005.
[3] A. K. Karimpoor, and U. Erb, "Mechanical properties of nanocrystalline
cobalt", Phys. Stat. Sol., vol. 203, pp. 1265-1270, 2006.
[4] B. W. Chua, L. Lu, and M. O. Lai, "Deformation behavior of ultrafine
and nanosize-grained Mg alloy synthesized via mechanical alloying",
Phil. Mag., vol. 86, pp. 2919-2939, 2006.
[5] S. Hwang, and C. Nishimura, "Compressive mechanical properties of
Mg-Ti-C nanocomposite synthesized by mechanical milling," Scr.
Mater, vol. 44, pp. 2457 -2462, 2001, pp. 123-135.
[6] Y. M. Wang, A. V. Hamza, and E. Ma, "Temperature-dependent strain
rate sensitivity and activation volume of nanocrystalline Ni," Acta
Mater, vol. 54, pp. 2715-2726, 2006.
[7] W. S. Lee, and C. F. Lin, "Plastic deformation and fracture behavior of
Ti-6Al-4V alloy loaded with high strain rate under various
temperatures", Mater. Sci. Eng. A, vol. 241, pp. 48-59 , 1998.
[8] Z. Trojanova, P. Lukac, and Z. Szaraz, "Deformation behavior of
nanocrystalline Mg studied at elevated temperatures", Rev. Adv. Mater.
Sci., vol. 10, pp. 437-441, 2005.
[9] G. E. Dieter, "Mechanical metallurgy, 3rd ed. Boston (MA), McGraw-
Hill, pp.462, 1986.
[10] M. O. Lai, L. Lu, and W. Laing, "Formation of nanocomposite via
mechanical milling, Composite structures, vol. 66, pp. 301 -304, 2004.
[11] Y. J. Chung, J. L. Park, N. J. Kim, and K. S. Shin, "Effect of alloying
elements on the mechanical properties of Mg-Al alloys", Materials
Science Forum, vol. 488 -489, pp. 845 -848, 2005.