Numerical and Experimental Evaluation of Stray Grains Formation During Single Crystal Growth

Document Type : Original Articles

Authors

Iran University of Science and Technology.

Abstract

Stray grain formation during single crystal growth with growth rates of 3, 5 and 7 mm/min has been assessed. The results revealed that increasing the growth rate resulted in the decrement of thermal gradient in the solidification front and caused stray grain formation in the solidification front of the columnar grain growth. Experimental and numerical results showed that a well-oriented single crystal structure is obtained at a growth rate of 3 mm/min in Ni-based superalloy. Stray grain formation occurred at growth rates greater than 3 mm/min, as a result of high growth rate and low thermal gradient.

Keywords


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