Document Type : Research Paper

Author

Production Engineering and Metallurgy, University of Technology, Baghdad, Iraq.

Abstract

Asymmetric rolling refers to the conditions wherein velocities or diameters of two work rolls are different. Compared to symmetrical rolling, asymmetric rolling is more effective on microstructure modification and texture evolution. Intense shear deformation can be introduced into asymmetric rolling to enhance the ductility and formability of aluminum alloy and this is the aim of current research. The process of the asymmetrical rolling was done on specimens with different reductions (10%,15%, and 20% reductions). Then the tensile test was conducted at room temperature at the strain rate range between 0.33×10-3s-1 - 3.33×10-3s-1 to study the ductility property of the asymmetric rolling-deformed samples and also compared with as-received samples. The results show that the as-received specimen gave the highest elongation of 42.7%, while the lowest elongation of 22.4% was obtained by the (20%) thickness reduction specimen. Also, the as-received sample at an initial strain rate of 3.33×10-3s-1 gives the highest tensile strength value equal to 550MPa.

Keywords

[1] S.B. Kang, B. Kimin, H. W. Kim, D. S. Wilkinson, and J. Kang, “Effect of asymmetric rolling on the texture and mechanical properties of AA6111-aluminum sheet, ” Metallurgical And Materials Transactions A, Vol. 36A, pp. 3141-3149, 2005.
[2] R.B. Megantoro, Loorentz and Y.G. Ko, “Temperature rise during differential speed rolling, ” Journal of Alloys and Compounds, Vol. 586, No. 1, pp. S254-S257, 2012.
[3] Loorentz, Y. G. Ko, “Effect of differential speed rolling strain on microstructure and mechanical properties of nanostructured 5052 Al Alloy, ” Journal of Alloys and Compounds, Vol. 586, No. c, pp. 205–209, 2014.
[4] W.J. Kim, H.W. Lee, S. J. Yoo, and Y.B. Park, “ Texture and mechanical properties of ultrafine-grained Mg-3AL-1 Zn alloy sheets prepared by high-ratio differential speed rolling, ” Materials Science & Engineering A, Vol. 528, No. 3, pp. 874-879, 2011.
[5] A. R. Ismail, Z. T. Madhloom, “Superplastic behavior of AZ31B magnesium alloy processed by equal channel angular pressing (ECAP), ” Eng. & Tech. Journal, Vol.32, Part (A), No.8, pp. 1958-1970, 2014.
[6] Loorentz and Y. Gun Ko “Microstructure evolution and mechanical properties of severely deformed al alloy processed by differential speed rolling, ” Journal of Alloys and Compounds, Vol. 536, No. 1, pp. S122-S125, 2012.
[7] H. Xinsheng, K. Suzuki, A. Watazu, I. Shigematsu and N. Saito, “Effects of thickness reduction per pass on microstructure and texture of Mg–3Al–1Zn alloy sheet processed by differential speed rolling, ” Scripta Materialia, Vol. 60, No. 11, pp. 964–967, 2009.
[8] H. A. Hiseb, N.A. Abdul Latif, and A.R. Ismail, “Super plasticity of ultra-fine-grained Mg-Alloy AZ31B using asymmetrical rolling,” Ph. D thesis, Production and Metallurgy Engineering Department, University of Technological, Baghdad, Iraq, 2017 .
[9] A.R. Ismail, E. A. Hussein, “Effect of differential speed rolling temperature into mechanical properties of AZ31B magnesium alloy, ” Eng. &Tech. Journal, Vol.34, Part (A), No.1, pp. 1-11, 2016.