Practical Electron Microscopy and Database

The phase diagram of nickel silicides is very complex and consists of various phases (some are shown in Figure 2475a). For instance, there are three polymorphic Ni₃Si structures (β₁, β₂ and β₃), Ni₃₁Si₁₂ (γ), NiSi₃(D0₃, D0₂₂), Ni₅Si₂ (D8_h),  two polymorphic Ni₂Si structures (δ = C23, and θ = B82), Ni₂Si (C37, D0₃, D0₂₂), Ni₃Si₂ (ε), NiSi (MnP), NiSi₂ (α= CaF₂, β),  Ni₃Si₂-ε', NiSi₂ (CaCl₂ = C35), and NiSi (L1₀). Even at room temperature, there are still 6 stable phases: Ni₃Si, Ni₃₁Si₁₂ or Ni₅Si₂, Ni₂Si, Ni₃Si₂, NiSi and NiSi₂. [4]

Figure 2475a. Si-Ni phase diagram.

Figure 2475b. Ti-Ni phase diagram. [1-3]

[1] K. Otsuka, X. Ren, Physical metallurgy of Ti–Ni-based shape memory alloys, Progress inMaterials Science 50 (2005) 511–678.
[2] Massalski TB, Okamoto H, Subramanian PR, Kacprzak L, editors. Binary alloy phase diagrams, 2nd edition, vol. 3. Materials Park, OH: ASM International; 1990. p. 2874.
[3] Otsuka K, Kakeshita T. MRS Bulletin2002;27:91.
[4] Handbook of Binary Alloy Phase Diagrams (CD Version 1.0), ASM International, ISBN PC-0-87170-562-1, (1996).