Ni-Cr thin films with chromium concentrations spanning the 0-100% rang
e were coevaporated onto NaCl substrates held at room temperature, 200
and 300 degrees C. Analytical transmission electron microscopy provid
ed complete identification of the phases present in the films and char
acterization of their microstructures. Films of 0-40% Cr contained gra
ins of the f.c.c. solid solution of chromium in nickel which, when for
med at 200 or 300 degrees C, exhibited {111}[11 $$($) over bar 2] twin
ning. Films of 50-70% Cr deposited onto room temperature substrates co
ntained nanocrystalline sigma phase, while larger grains of sigma phas
e were found for elevated substrate temperature depositions. Films of
80% Cr, deposited onto 300 degrees C substrates, contained delta phase
with the A15 structure in addition to the b.c.c. solid solution of ni
ckel in chromium observed in films deposited onto lower temperature su
bstrates. These observations are discussed in terms of thermodynamic c
alculations and electron phase considerations as they apply to the Ni-
Cr alloy system.