OJMetal  Vol.3 No.2 A , July 2013
Equal Channel Angular Pressing of Al-SiC Composites Fabricated by Stir Casting

Stir casting method was used to produce conventional metal matrix composites (MMC) with fairly homogenous dispersion of reinforcement material. Commercial pure aluminum and silicon carbide particles (50 μm) were selected as matrix and reinforcement materials respectively. The matrix was first completely melt and kept constant at 750°C. Then SiC powder preheated to 800°C was added during stirring action. No wetting agents were used. The melt mixture was poured into a metallic mold. The composite contents were adjusted to contain 5% and 10% SiC. The as-cast composites were processed by Equal Channel Angular Pressing (ECAP) route A. The microstructure and mechanical properties were studied. Results indicated that as cast AlSiC composites can be successfully fabricated via a cheap conventional stir casting method, giving fairly dispersed SiC particle distribution and having low porosity levels < 3.6%. The mechanical properties have improved compared to as cast composites. ECAP technique has greatly reduced SiC particles from 50 to 3 μm. After the first ECAP pass, yield strength has almost twice its value in the as cast composites. The maximum yield of 245 MPa obtained after 8 passes is almost four times the corresponding values of the as cast MMC composites. Hardness has also increased to 1.5 times its value in the as cast composites after one ECAP pass. The maximum hardness of 71 HRB obtained after 8 passes, which is almost 3.5 times the corresponding values of the as cast MMC composites.

Cite this paper
F. Shehata, N. ElMahallawy, M. Arab and M. Agwa, "Equal Channel Angular Pressing of Al-SiC Composites Fabricated by Stir Casting," Open Journal of Metal, Vol. 3 No. 2, 2013, pp. 26-33. doi: 10.4236/ojmetal.2013.32A1004.
[1]   T. W. Cline and P. J. Withers, “An Introduction to Metal Matrix Composites,” Cambridge University Press, Cambridge, 1995.

[2]   D. B. Miracle, “Metal Matrix Composites—From Science to Technological Significance,” Composites Science and Technology, Vol. 65, No. 15, 2005, pp. 2526-2540. doi:10.1016/j.compscitech.2005.05.027

[3]   D. J. Lloyd, “Particle Reinforced Aluminum and Magnesium Matrix Composites,” International Materials Reviews, Vol. 39, No. 1, 1994, pp. 1-23. doi:10.1179/095066094790150982

[4]   S. Ray, “Synthesis of Cast Metal Matrix Particulate Composites,” Journal of Materials Science, Vol. 28, No. 20, 1993, pp. 5397-5413. doi:10.1007/BF00367809

[5]   L. Cronjager and M. Dietmar, “Drilling of Fibre and Particle Reinforced Aluminum,” Composite Material Technology, Vol. 37, 1991, pp. 185-189.

[6]   M.-R. Chen, et al., “Microstructure and Properties of Al0.5CoCrCuFeNiTix (x = 0 - 2.0) High-Entropy Alloys,” 2006.

[7]   P. K. Rohatgi, “Low-Cost, Fly-Ash-Containing Aluminum-Matrix Composites,” JOM, Vol. 46, No. 11, 1994, pp. 55-59. doi:10.1007/BF03222635

[8]   M. I. Pech-Canul, “Aluminum Alloys for Al/SiC Composites,” Recent Trends in Processing and Degradation of Aluminum Alloys, 2011, pp. 299-314.

[9]   Y. Cui, “High Volume Fraction SiCp/Al Composites Prepared by Pressureless Melt Infiltration: Processing, Properties and Applications,” Key Engineering Materials, Vol. 249, 2003, pp. 45-48. doi:10.4028/www.scientific.net/KEM.249.45

[10]   M. K. Surappa, “Microstructure Evolution during Solidification of DRMMC,” Journal of Materials Processing Technology, Vol. 63, 1997, pp. 325-333. doi:10.1016/S0924-0136(96)02643-X

[11]   D. M. Skibo, D. M. Schuster and L. Jolla, “Process for Preparation of Composite Materials Containing Non-Metallic Particles in a Metallic Matrix, and Composite Materials,” US Patent No. 4786467, 1988.

[12]   D. J. Lloyd, “Aspects of Fracture in Particulate Reinforced Metal Matrix Composites,” Acta metallurgica et materialia, Vol. 39, No. 1, 1991, pp. 59-71. doi:10.1016/0956-7151(91)90328-X

[13]   Y. M. Youssef, R. J. Dashwood and P. D. Lee, “Effect of Clustering on Particle Pushing and Solidification Behavior in TiB2 Reinforced Aluminum PMMCs,” Composites Part A: Applied Science and Manufacturing, Vol. 36, No. 6, 2005, pp. 747-763. doi:10.1016/j.compositesa.2004.10.027

[14]   T. Iseki, T. Kameda and T. Maruyama, “Interfacial Reactions between SiC and Aluminum during Joining,” Journal of Materials Science, Vol. 19, No. 5, 1984, pp. 1692-1698. doi:10.1007/BF00563067

[15]   I. Sabirov, O. Kolednik, R. Z. Valiev and R. Pippan, “Equal Channel Angular Pressing of Metal Matrix Composites,” Acta Materialia, Vol. 53, 2005, pp. 4919-4930. doi:10.1016/j.actamat.2005.07.010

[16]   S. Tzamtzis, et al., “Processing of Advanced Al/SiC Particulate Metal Matrix Composites under Intensive Shearing—A Novel Rheo-Process,” Composites Part A: Applied Science and Manufacturing, Vol. 40, No. 2, 2009, pp. 144-151. doi:10.1016/j.compositesa.2008.10.017

[17]   H. Rumpf, “The Strength of Granules and Agglomerates,” Agglomeration, Interscience, New York, 1962, pp. 379-413.

[18]   P. N. Bindumadhavan, T. K. Chia, M. Chandrasekaran, H. K. Wah, L. N. Lam and O. Prabhakar, “Effect of Particle Porosity Clusters on Tribological Behavior of Cast Aluminium Alloy A356-SiCp Metal Matrix Composites,” Materials Science and Engineering: A, Vol. 315, No. 1-2, 2001, pp. 217-226. doi:10.1016/S0921-5093(00)01989-4

[19]   M. Kok, “Production and Mechanical Properties of Al2O3 Particle-Reinforced 2024 Aluminum Alloy Composites,” Journal of Materials Processing Technology, Vol. 161, No. 3, 2005, pp. 381-387. doi:10.1016/j.jmatprotec.2004.07.068

[20]   J. W. Martin, R. D. Doherty and B. Cantor, “Stability of Microstructure in Metallic Systems,” Cambridge University Press, Cambridge, 1997. doi:10.1017/CBO9780511623134

[21]   T. Inoue, Z. Horita, H. Somekawa and K. Ogawa, “Effect of Initial Grain Sizes on Hardness Variation and Strain Distribution of Pure Aluminum Severely Deformed by Compression Tests,” Acta Materialia, Vol. 56, No. 20, 2008, pp. 6291-6303. doi:10.1016/j.actamat.2008.08.042