Effects of Nb content on the Zr2Fe intermetallic stability

Some new experimental results on the Zr–Nb–Fe system

“…-The lower existence range with respect to the Fe content, taking into account the present work and previous works results [1][2][3][4], was about 30 at.% Fe, 34 at.% Zr and 36 at.% Nb and the upper one was about 55 at.% Fe, 5 at.% Nb and 40 at.% Zr for the k 2 phase. -In addition to the well-known Laves C15-type (ZrNb)Fe 2 phase (the polytypic C14 and C36 structures were not detected in the studied compositions), another Laves C14-type phase was found (k 2 : Zr(NbFe) 2 ).…”

“…At 900°C has a wide range of compositions. Comparing the obtained values to our previous work [1][2][3][4] for alloys with variable compositions and considering that those values do not contradict values found in literature for precipitates of this phase in different Zr alloys [5,7,[18][19][20][21], we could say that this phase would extend over the following composition range: 34 < at.% Zr < 40, 5 < at.% Nb < 36, 30 < at.% Fe < 55. Then, the lower existence range of this phase respecting the Fe content would be around 30 at.% Fe, 36 at.% Nb and 34 at.% Zr and the upper existence range respecting the Fe content would be around 55 at.% Fe, 5 at.% Nb and 40 at.% Zr.…”

“…Two solid solutions (b-Zr and b-Nb), two Laves phases (Zr(NbFe) 2 and (ZrNb)Fe 2 ) and the (ZrNb) 2 Fe intermetallic appeared in the composition range studied in the present work. From now on the (ZrNb) 2 Fe phase will be referred as k 1 phase and the Zr(NbFe) 2 phase as k 2 phase to be consistent with [4].…”

“…One of the ternary phases found in the present work is a cubic Ti 2 Ni-type phase, (ZrNb) 2 Fe [1][2][3][4][5][6], another one is a hexagonal C14 Laves Zr(NbFe) 2 phase [2][3][4][5][6][7] and the last one a cubic C15 Laves phase, (ZrNb)Fe 2 . The latter is a polytypic phase which presents cubic C15 [2,4,8], hexagonal C36 [2] and hexagonal C14-type [2,8] structures depending on the composition. These structures occur on the ZrFe 2 -NbFe 2 line of the Zr-Nb-Fe phase diagram [6].…”

“…This cubic Ti 2 Ni-type phase formed from the tetragonal Zr 2 Fe intermetallic with Nb content greater than 0.5 at.% [1][2][3][4], presents a wide range of composition stability at 900°C for the studied samples. Nb contents in this phase increase with Nb contents in the alloys.…”