|
NISCAIR ONLINE PERIODICALS REPOSITORY (NOPR) >
NISCAIR PUBLICATIONS >
Research Journals >
Indian Journal of Engineering and Materials Sciences (IJEMS) >
IJEMS Vol.15 [2008] >
IJEMS Vol.15(3) [June 2008] >
| Title: | Nucleation kinetics studies on embedded nanosized indium (In) particles |
| Authors: | Chaubey, Sanjay |
| Issue Date: | Jun-2008 |
| Publisher: | CSIR |
| Abstract: | Indium exhibits a monotectic reaction with Al at an invariant temperature (910 K) and composition (4.7 at.% In). Ultra rapid cooling, using gun technique, of monotectic compositioned alloy led to a microstructure in which In was distributed uniformly with a bimodal size distribution. Quantitative metallographic analysis revealed size of small sized In particles to be in the range of 10-20 nm whereas bigger particles were found to be even greater than 200 nm in size. These particles of In undercooled by 19 K in the rapidly solidified product of Al-In system. In the as-cast condition the degree of undercooling was only 9 K. Analyses of the nucleation rate measurements showed that the activation energy barrier to nucleation is
2.666 kcal/mol at undercoolings approaching 19 K. The nucleus-substrate contact angle was found to be 20°, which signifies that Al provides a potent catalytic surface for the nucleation of In. |
| Page(s): | 241-246 |
| ISSN: | 0971-4588 |
| Source: | IJEMS Vol.15(3) [June 2008]
|
|