M.S. Salleh, N.N.M. Ishak, S.H. Yahaya, Sivaraos `, A. Abdullah


This work investigated the effect of equal channel angular pressing (ECAP) on the microstructure and mechanical properties of non-dendritic A356 alloy. This alloy was casted by cooling slope casting in order to produce a globular microstructure feedstock for ECAP process. After that, ECAP process was performed using 120° of die angle via route A for 2 passes at room temperature. The microstructure of the processed alloys was observed under an optical microscope (OM) and scanning electron microscope (SEM) whereas the mechanical properties of the alloy were validated using Vickers hardness test and tensile test. Microstructure observation showed that after 2 passes, the grain size was obviously refined to 35 µm from 75 µm in the as-cast sample. The mechanical properties of the alloy were ultimately improved in ECAP sample. The hardness of the ECAP sample increased as high as 77.6 HV as compared to the as-cast alloy which was 42.3 HV. The ultimate tensile strength also increased from 105 MPa to 237 MPa after 2 passes deformation. It was also discovered that the distribution of α-Al and eutectic phases were more homogeneous at the ECAP sample than using non-dendritic structure feedstock.

Full Text:



V. M. Segal, “Equal channel angular extrusion: From macromechanics to structure formation,” Materials Science and Engineering: A, vol. 271, no. 1-2, pp. 322-333, 1999.

Z.J. Zheng, Y.Gao, J.W.Liu and M.Zhu, “A hybrid refining mechanism of microstructure of 304 stainless steel subjected to ECAP at 500°C,” Materials Science and Engineering: A, vol. 639, pp. 615-625, 2015.

A. Azushima, R. Kopp, A. Korhonen, D.Y. Yang, F. Micari, G.D. Lahoti, P. Groche, J. Yanagimoto, N. Tsuji, A. Rosochowski and A. Yanagida, “Severe Plastic Deformation (SPD) Processes for Metals,” CIRP Annals- Manufacturing Technology, vol. 57, no. 2, pp. 716-736, 2008.

J. S. Carpenter, T. Nizolek, R. J. McCabe, M. Knezevic, S. J. Zheng, B. P. Eftink, J. E. Scott, S. C. Vogel, T. M. Pollock, N. A. Mara and I. J. Beyerlein, “Bulk texture evolution of nanolamellar Zr- Nb composites process via accumulative roll bonding,” Acta Materialia, vol. 92, pp. 97- 108, 2015.

F. Khodabakhshi, M. Haghshenas, H. Eskandari and B. Koohbor, “ Hardness- strength relationships in fine and ultra-fine grained metals processed through constrained groove pressing,” Materials Science and Engineering: A, vol. 636, pp. 331-339, 2015.

N. Haghdadi, A. Zarei-Hanzaki, H. R. Abedi, D. Abou-Ras, M. Kawasaki and A. P. Zhilyaev, “Evolution of microstructure and mechanical properties in a hypoeutectic Al-Si-Mg alloy processed by accumulative back extrusion,” Materials Science and Engineering: A, vol. 651, pp. 269-279, 2016.

F. Reshadi, G. Faraji, S. Aghdamifar, P. Yavari and M. M. Mashhadi, “Deformation speed and temperature effect on magnesium AZ91 during tubular channel angular pressing,” Materials Science and Technology, vol. 31, no. 15, pp. 1879- 1885, 2015.

S. V. Dobatkina, O. V. Rybalchenko, N. A. Enikeev, A. A. Tokar and M. M. Abramova, “Formation of fully austenitic ultrafine-grained high strength state in metastable Cr–Ni–Ti stainless steel by severe plastic deformation,” Materials Letters, vol. 166, pp. 276- 279, 2016.

Y. Estrin and A. Vinogradov, “Extreme grain refinement by severe plastic deformation: A wealth of challenging science,” Acta Materialia, vol. 61, no. 3, pp. 782-817, 2013.

M. Chegini, A. Fallahi and M. H. Shaeri, “Effect of equal channel angular pressing (ECAP) on wear behaviour of Al- 7075 alloy,” Procedia Materials Science, vol. 11, pp. 95- 100, 2015.

M.I.A. El Aal, “Influence of the pre-homogeneous treatment on the microstructure evolution and the mechanical properties of Al- Cu alloy processed by ECAP,” Materials Science and Engineering: A, vol. 528, no. 22-23, pp. 6946- 6957, 2011.

M. A. H. Safian, M. S. Salleh, N. I. S. Hussein, M. A. Sulaiman and S. H. Yahaya, “Production of LM4 Feedstock for Thixoforming by Using Cooling Slope Casting” Journal of Advanced Manufacturing Technology, vol. 11, no. 1, pp. 77-90, 2017.

K. S. Alhawari, M. Z. Omar, M. J. Ghazali, M. S. Salleh and M. N. Mohammed, “Dry sliding wear behaviour of thixoformed hypoeutectic Al–Si–Cu alloy with different amounts of magnesium,” Composites Interfaces, vol. 23, no. 6, pp. 519- 531, 2016.

M. S. Salleh, M. Z. Omar, J. Syarif, K. S. Alhawari, and M.N. Mohammed, “Microstructure and mechanical properties of thixoformed A319 aluminium alloy,” Materials & Design, vol. 64, pp. 142-152, 2014.

E. Ruckenstein, G. O. Berim and G. Narsimhan, “A novel approach to the theory of homogeneous and heterogeneous nucleation,” Advances in Colloid and Interface Science, vol. 215, pp. 13-27, 2015.

F. Taghavi and A. Ghassemi, “Study on the effects of the length and angle of inclined plate on the thixotropic microstructure on A356 aluminium alloy,” Materials & Design, vol. 30, no. 5, pp. 1762-1767, 2009.

N. V. Thuong, H. Zuhailawati, A. A. Seman and T. D. Huy, “Microstructural evolution and wear characteristics of equal channel angular pressing processed semi- solid- cast hypoeutectic aluminium,” Materials & Design, vol. 67, pp. 448-456, 2015.

Y. J. Chen, Y. C. Chai, H. J. Roven, S. S. Gireesh, Y. D. Yu and J. Hjelen, “Microstructure and mechanical properties of Al-xMg alloys processed by room temperature ECAP,” Materials Science and Engineering: A, vol. 545, pp. 139-147, 2012.

M. Moradi, M. Nili- Ahmadabadi and B. Heidarian, “Improvement of mechanical properties of AL (A356) cast alloy processed by ECAP with different heat treatments,” International Journal of Material Forming, vol. 2, no. 1, pp. 85-88, 2009.

M. I. A. El Aal and M. M. Sadawy, “Influence of ECAP as grain refinement technique on microstructure evolution, mechanical propertied and corrosion behaviour of pure aluminium,” Transactions of Nonferrous Metals Society of China, vol. 25, no. 12, pp. 3865-3876, 2015.

© Journal of Advanced Manufacturing Technology