Al-Ce-Ni (Aluminum-Cerium-Nickel)

  • PDF / 287,067 Bytes
  • 3 Pages / 593.972 x 792 pts Page_size
  • 83 Downloads / 228 Views

DOWNLOAD

REPORT


Phase Diagram Evaluations: Section II

Al-Ce-Ni (Aluminum-Cerium-Nickel) V. Raghavan

The early report on the phase equilibria of this ternary system by [1983Zar] presented partial isothermal sections at 800, 600, and 500 C for Ce concentrations up to 33.3 at.%, depicting a number of ternary compounds. Recently, [2008Tan] reinvestigated the system at 800 C and found two new ternary compounds of unknown structure. The solidiļ¬cation features near the Al corner were studied by [1996Bel].

Table 1

AlCeNi (s1)

Al2CeNi (s2)

Al5Ce2Ni5 (s3)

Al3CeNi2 (s4)

Al4CeNi (s5)

Al5CeNi2 (s6)

Al7CeNi2 (s7)

Al23Ce4Ni6 (s8)

Al17Ce40Ni43 (s9)

AlCeNi4 (s10)

s12

The Al-Ce phase diagram was recently reassessed thermodynamically by [2005Gao], using new experimental results as additional input. The intermediate phases in this system are: aCe3Al (D019, Ni3Sn-type hexagonal), bCe3Al (L12, AuCu3-type cubic), Ce2Al (stable between 775 and

Al-Ce-Ni crystal structure and lattice parameter data [2008Tan]

Phase

s11

Binary Systems

Composition, at.% 36.4-34.1 Al 33.0-32.7 Ce 30.6-33.2 Ni 53.0-50.7 Al 24.5-26.9 Ce 22.5-22.4 Ni 41.7 Al 16.7 Ce 41.7 Ni 50.0 Al 16.7 Ce 33.3 Ni 66.7 Al 16.7 Ce 16.7 Ni 62.5 Al 12.5 Ce 25.0 Ni 70 Al 10 Ce 20 Ni 69.7 Al 12.1 Ce 18.2 Ni 17 Al 40 Ce 43 Ni 16.7 Al 16.7 Ce 66.7 Ni 59.8 Al 12.1 Ce 28.1 Ni 40.3 Al 30.4 Ce 29.3 Ni

Pearson symbol

Space group

Prototype

Lattice parameter, nm

hP9

P62m

Fe2P

a = 0.69927-0.69745 c = 0.40276-0.40155

oC16

Cmcm

Al2CuMg

a = 0.40741-0.40774 b = 1.09631-1.09750 c = 0.69373-0.69442 ...

...

...

hP6

P6/mmm

CaCu5

a = 0.528 c = 0.404

oC24

Cmcm

Al4NiY

oI16

Immm

Al5Ni2Pr

a= b= c= a= b= c=

0.4097 1.547 0.6643 0.7030 0.9597 0.3999 ...

a= b= c= b= a= b= c= a= c=

1.6042 0.4140 1.8380 113.24 0.5331 0.8403 0.4241 0.4943 0.4085 ...

...

...

...

...

mC66

C2/m

Al23Y4Ni6

oI?

Immm

MoNi2B2

hP6

P6/mmm

CaCu5

...

...

...

...

...

...

Journal of Phase Equilibria and Diffusion Vol. 30 No. 3 2009

...

265

Section II: Phase Diagram Evaluations

Fig. 1 Al-Ce-Ni isothermal section at 800 C for Ce-lean alloys [2008Tan]

Ternary Compounds A total of 12 ternary compounds are known in this system. The structural details of these are shown in Table 1 [2008Tan]. The ternary compounds AlCeNi (s1) and Al2CeNi (s2) show a measurable homogeneity range and a corresponding variation in the lattice parameters, Table 1. The compounds Al5Ce2Ni5 (s3), Al3CeNi2 (s4), Al7CeNi2 (s7), and Al17Ce40Ni43 (s9) were not found by [2008Tan] at 800 C. The compound s10 is a solid solution based on the binary compound CeNi5. The composition variation in the compounds Al4CeNi (s5), Al5CeNi2 (s6), and Al23Ce4Ni6 (s8) was found to be very small [2008Tan]. The compounds s11 and s12 were newly found by [2008Tan], but the crystal structures were not determined.

Ternary Phase Equilibria

Fig. 2 Al-Ce-Ni liquidus projection near the Al corner [1996Bel]

648 C; Co2Si-type orthorhombic?), CeAl (orthorhombic), CeAl2 (C15, MgCu2-type cubic), aCeAl3 (Ni3Sn-type hexagonal), bCeAl3 (hexagonal, sta

Data Loading...