Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1559142 | Calphad | 2009 | 5 Pages |
Abstract
A calorimetric study of alloys along the section TiZn3-TiAl3 is carried out to determine their heat of formation (ÎfHâ) at 300 K using a high temperature direct drop calorimeter. The target compositions of the alloys lie in the range of 10-65 at.% Al. The structure and composition of the reacted samples are characterized by X-ray diffraction and electron probe microanalysis. The following values of ÎfHâ (in kJ/mol-atom) at 300 K are obtained (by interpolation) for L12- Ti(Zn,Al)3 solid solution: â27±1 (at Ti25Zn65Al10), â30±1 (at Ti25Zn55Al20), â32±1 (at Ti25Zn45Al30), â34±1 (at Ti25Zn35Al40), â35±1 (at Ti25Zn25Al50) and â36±1 (at Ti25Zn15Al60). Calorimetric data are compared with the formation energy of L12- Ti(Zn,Al)3 alloys calculated from first-principles and sublattice cluster expansion, showing a very good agreement. Stabilization of L12- Al3Ti, by substituting Zn for Al, offers a potential to introduce it as strengthening precipitates in Al alloys.
Related Topics
Physical Sciences and Engineering
Materials Science
Materials Science (General)
Authors
S. Delsante, G. Ghosh, G. Borzone,