Effect of slope casting method combined with melt treatment on morphology of silicon in Al-17% Si alloy

Document Type : Original Articles

Authors

• bahman korojy
• kaveh ghorbani

Hakim Sabzevari University

10.22067/ma.v26i1.23773

Abstract

Inthis investigation, the slope casting method was used and its combined effect with melt overheating and melt treatmenton microstructural modification and hardness of hypereutectic Al–Si alloy was studied. The results showed that the combined method leads to the refinement of primary silicon and a change in its morphology from plate-like to quasi-spherical shape. In addition, the modification and refinement of primary silicon increased the hardness of hypereutectic Al-Si alloy.

Keywords

• Al-Si alloy
• slop casting
• melt treatment
• silicon morphology

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References

Gupta, M., and Ling, S.,''Microstructure and mechanical properties of hypo/hyper-eutectic Al-Si alloys synthesized using near-net shape forming technique'', Journal of Alloys and Compounds,pp. 284-294, (1999).

2. Kyffin, W., Rainforth,W. and Jones, H.,''Effect of treatment variables on size refinement by phosphide inoculants of primary silicon in hypereutectic Al-Si alloys'',Materials Science and Technology, pp. 901-905, (2001).

3. Li,P., Nikitin,V.I.,and.Kandalova,E.G ,''Effect of melt overheating, cooling and solidification rates on Al-16%Si alloy structure'',Materials Science and Engineering A,pp. 371-374, (2002).

4. Chong,C., Zhong,L.I.and Bo,R.E.,''Influences of complex modification of P and RE on microstructure and mechanical properties of hypereutectic Al-20Si alloy'',Transactions of Nonferrous Metals Society of China, pp. 301-306, (2007).

5. Bian,X.,Ma,J. and Ma,Z., ''Thermal-rate treatment of molten Al-Si alloys", Chinese Journal of Mechanical Engineering,Vol. 5, pp. 176-182, (1992).

6. Bian,X., Qin,J. and Wang,S.i., ''The atomic-structhre changes in Al-16%Si alloy above the liquidius'', Metallurgical and Materials Transactions A,pp. 2163-2168, (2000).

7. Xu,C.L. and Jiang,Q.C, ''Morphologies of primary silicon in hypereutectic Al-Si alloys with melt overheating temperature and cooling rate'',Materials Science and Engineering A, pp. 451-455, (2006).

8. Diewwanit,A., ''Semi-solid processing of hypereutectic aluminum–silicon alloys'', MIT, (1996).

9. Hga, T. and Kapranos,P., ''Microstructure at Semi-solid condition of Al alloy Strip Cast using a Twin Roll Caster'', 7th Int. Conf. on Semi-Solid Proc.Of Alloys and Composites, Japan, (2002).

10. Hga, T. and Kapranos,P., ''Rheocasting Processes using a Cooling Slope plate Low Superheat Casting'', 7th Int. Conf. on Semi-Solid Proc. of Alloys and Composites, Japan, ( 2002).

11. Birol,Y.,''Cooling slope casting and thixoforming of hypereutectic A390 alloy'', Journal of Materials processing Technology, pp. 200-203, (2008).

12. Birol,Y.,''A357 thixoforming feedstock produced by cooling slope casing'', Journal of Materials processing Technology, pp. 94-101, (2007).

13. Hekmat-Ardakan, Alireza.Ajersch, Frank.''Effect of isothermal aging on the semi-solid microstructure of rheoprocessed and partially remelted of A390 alloy with 10% Mg addition'', Material Characterization, pp.778-785, (2010).

14. Taghavi,F. and GhasemiA.,''Study on the effects of the length and angle of inclined plate on the microstructure of A356 aluminum alloy'',Material and Design, pp.1762-1767,(2009).

15. Birol,Y.,''Semi-solid processing of the primary aluminum die casting alloy A365'' ,Journal of Alloys and Compounds, pp. 133-138, (2009).

16. Haga,T. and Suzuki,Sh.,''Casting of aluminum alloy ingots for thixoforming using a cooling slope'',Journal of Materials Processing Technology, pp. 169-172, (2001).

17. Fredriksson, H. and Akerlind, A.,"Materials Processing during Casting", John Wiley & Sons, Ltd., Chichester, pp. 77-86, (2006).

18. Bian, X. and Wang,W., ''Thermal-rate treatment and structure transformation of Al-13%Si alloy melt'', Materials Letters, pp. 54-58, (2000).

19. Sun,Y., Wang, Q.and Geng,H.,''Effects of complex modificating technique on microstructure and mechanical properties of hypereutectic Al-Si alloys'', Journal of Materials Science, pp. 2104-2109, (2012).

20. West, R. and Fredrikssson, H., ''On the mechanism of facetted growth'', Journal of Materials Science, pp. 1061-1068, (1985).

21. Dai,H.S. and Liu,X.F., ''Optimal holding temperatures and phosphorus additions for primary silicon refinement in Al-high Si alloys'',Materials Science and Technology, pp. 1183-1188, (2009).

22. Langer, E., "ASM Handbook, Vol. 3", ASM International, USA, pp.1105, (1998).

23. Zhang,J., Fan, Z.and Zhou, L., ''Microstructure development of Al-15% Mg2Si in situ composite with mischmetal addition'',Materials Science and Engineering A, pp. 104-112,(2000).

24. Nogita,K., Drennan, J.and Dahle,A.,''Evaluation of Silicon Twinning in Hypoeutectic Al-Si alloys'',Materials Transactions, pp. 625-628, (2003).

25. Chang, J., Moon, I. and Choi, C., ''Refinement of cast microstructure of hypereutectic Al-Si alloys through the addition of rare earth metals'', Journal of Materials Science, Vol. 33, pp. 5015-5023,(1998).

26. قلم باز، م. ، شاهمیری، م. و کریم خرازی.، '' بررسی اثر سطح شیبدار روی سیلیسیم اولیه و سیلیسیم یوتکتیک در آلیاژ A390 ''،ششمین همایش علمی-دانشجویی مهندسی مواد و متالورژی،دانشگاه علم و صنعت ایران، (1385).

27. Jiang, Q.C., Xu, C.L., Lu, M.and Wang,H.Y., ''Effect of new Al-P-Ti-TiC-Y modifier on primary silicon in hypereutectic Al-Si alloys'',Materials Letters, pp. 624-628,(2005).