Solidification Reaction Sequence of Co-Rich Nb-Al-Co Alloys |
| |
Authors: | L. M. Feitosa N. D’Souza G. D. West H. B. Dong |
| |
Affiliation: | 1.Department of Engineering,University of Leicester,Leicester,UK;2.Rolls-Royce plc,Derby,UK;3.Warwick Manufacturing Group,University of Warwick,Coventry,UK |
| |
Abstract: | The freezing reaction sequence of Co-rich Nb-Al-Co ternary alloys with emphasis on the formation of Laves and Heusler phases has been examined. For Co-rich alloys, the solidification reaction sequence is observed as primary freezing of α-Co and CoAl phases, subsequent [Co + C36] and [CoAl + C36] eutectics, and the final ternary eutectic reaction [L → α-Co + C36 + CoAl]. The compositions of solidified α-Co and C36 phases agree with the corresponding vertices of the tie-triangle at the solidus temperatures. When the Nb concentration is over 20 at. pct in Co-rich alloys, the quasi-peritectic reaction [L + Co2AlNb → C36 + CoAl] does not occur as equilibrium prediction. The formation of C36 and CoAl phases occurs through solid precipitation and must be distinguished from a solidification reaction. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|