Relationship between columnar crystal spacing and electric current density in unidirectional solidification of monophase Cu-Al alloy
(1. Department of Materials and Chemical Engineering,
Liaoning Institute of Technology，Jinzhou 121001, China;
2. Guangzhou Nonferrous Metals Institute, Guangzhou 510651, China;
3. School of Materials Science and Engineering,
University of Science and Technology Beijing,Beijing 100083, China)
Liaoning Institute of Technology，Jinzhou 121001, China;
2. Guangzhou Nonferrous Metals Institute, Guangzhou 510651, China;
3. School of Materials Science and Engineering,
University of Science and Technology Beijing,Beijing 100083, China)
Abstract: On the basis of previous theoretical inferential relationship between the columnar crystal spacing and the density of electric current applied during unidirectional solidification, the effect of current density on the columnar crystal spacing was discussed and analyzed, and the experiment was made to verify the theoretical relationship. The results show that at fast solidification speed the columnar crystal spacing decreases with increasing the density of electric current, while at slow solidification speed the columnar crystal spacing increases with increasing the density of electric current. The critical conditions for the evolution of columnar crystal spacing were confirmed. The calculated values concerning the spacing and the density are consistent with the experimental results.
Key words: unidirectional solidification; columnar crystal spacing; effect of electric current; Cu-Al alloy