Effect Of Friction Stir Processing On Mechanical Properties And Microstructure Of The Cast Pure Aluminum

Abstract: Friction stir processing (FSP) has the potential for locally enhancing the properties of pure AL. A cylindrical tool with threaded pin was used. the effect of FSP has been examined on sand casting hypereutectic pure AL. The influence of different processing parameters has been investigated at a fundamental level. Effect of (FSP) parameters such as transverse speed (86,189,393) mm/min, rotational speed (560,710, 900) rpm on microstructure and mechanical properties were studied. Different mechanical tests were conducted such as (tensile, microhardness and impact tests). Temperature distribution has been investigated by using infrared (IR) camera; the thermal images were analyzed to point out the temperature degree on limited points. The results show that the heat generation increase when rotational speed increase and decrease when transverse speed increase. Hardness and impact measurements were taken across the process zone( PZ), and tensile testing were carried out at room temperatures. After FSP, the microstructure of the cast pure Al was greatly refined. However, FSP caused very little changes to the hardness of the material, while tensile and impact properties were greatly improved.

REFERENCES

[1]. R.S. Mishra, M.W. Mahoney, S.X. McFadden, N.A. Mara, and A.K. Mukherjee: Scripta Mater., vol. 42, pp. 163�68.( 2000).

[2]. Z.Y. Ma, R.S. Mishra, and M.W. Mahoney: Acta Mater., vol. 50, pp. 4419�4430 ( 2002).

[3]. R.S. Mishra, Z.Y. Ma, and I. Charit: Mater. Sci. Eng., A,vol. A341, pp. 307�310 ( 2002).

[4]. P.B. Berbon, W.H. Bingel, R.S. Mishra, C.C. Bampton, and M.W. Mahoney: Scripta Mater., vol. 44, pp. 61�66(2001).

[5]. Z.Y. Ma, S.R. Sharma, R.S. Mishra, and M.W. Mahoney: Mater. Sci. Forum, , vols. 426�432, pp. 2891�96(2003).

[6]. Colegrove, P.A., Shercliff, H.R. �Experimental and numerical analysis of aluminium alloy 7075-T7351 friction stir welds�, Science and Technology of Welding and Joining; Vol.8 No.5: pp.360-368(2003)

[7]. Colegrove, P.A., Shercliff, H.R., Zettle, R. �Model for predicting heat generated and temperature in friction stir welding from the material properties�, Science and Technology of Welding and Joining; 12: pp.284-297(2007).

[8]. R.S. Mishra, Z.Y. Ma, and I. Charit" Friction stir processing: a novel technique for fabrication of surface composite, Mater. Sci. Eng., A, ,vol. A341, pp. 307�310(2003).

[9]. Thaiping Chen "Process Parameters Study on FSW Joint of Dissimilar Metals for Aluminum�Steel" J. Mater Sci. Vol. 44, pp. 2573�2580 (2009).

[10]. Wang, Q.G., Apelian, D., Lados, D.A. �Fatigue behaviour of A356-T6 aluminium cast alloys. Part I. Effect of casting defects�, Journal of Light Metal; 1: 73-84(2001)

[11]. Lee, M.H., Kim, J.J., Kim, K.H., Kim, N.J., Lee, S., Lee, E.W. �Effects of HIPping on high-cycle fatigue properties of investment cast A356 aluminium alloys�, Materials Science and Engineering A; 340: 123-129(2003).