The Effect of Production Parameters on Secondary Dendrite Arm Spacing (SDAS) and Estimation of Cooling Rate by SDAS in Functionally Graded Al-Cu Eutectic Alloy

Authors : Semih Ağca

Pages : 36-41

View : 22 | Download : 7

Publication Date : 2017-11-29

Article Type : Other

Abstract :In this study, the effect of production parameters (G number, casting atmosphere, and cooling rate) on secondary dendrite arm spacing (SDAS) and estimation of cooling rate by SDAS in functionally graded Al-Cu eutectic alloy are investigated. Functionally graded Al-Cu eutectic alloy is fabricated by centrifugal casting method. Different productions are carried out by changing cooling rate, G number and casting atmosphere. Cooling rate is controlled by a novel mold design and 0,09 K/s, 1,04 K/s, 1,96 K/s and 2,82 K/s cooling rates are obtained by using this mold. 10, 20 and 30 G numbers are obtained by changing the mold rotation speed. Air and 200 mBar vacuum atmospheres are preferred as casting atmospheres. SDASs are measured by Leica Application Suite V 4.6 image analysis software. Apparent interlamellar spacing is used in measurements. It is found that cooling rate alteration has a significant influence on SDAS. In addition to this, G number and casting atmosphere affected the SDAS by affecting the cooling rate. SDAS increased with the decreasing of cooling rate. Successful results are obtained in cooling rate estimation.  
Keywords : Aluminum alloys, FGM, SDAS, cooling rate