An investigation into the phase equilibria of the Al-rich portion of t
he Ti-Al-Cr ternary system was carried out using both bulk alloy and d
iffusion couple samples. Combination of the data from the samples enab
led the construction of partial isothermal sections at 1000 and 800 de
grees C. Further, the Ti(Cr,Al)(2) + tau --> beta(Cr) + TiAl2 invarian
t reaction was found to occur between 1000 and 800 degrees C. In addit
ion to the above reaction a precursor invariant reaction, TiAl + tau -
-> Ti(Cr,Al)(2) + TiAl2, also occurs between those temperatures. Due t
o the recession of the beta(Cr) phase with decreasing temperature and
the formation of the Cr2Al phase, the beta(Cr) + tau --> Cr2Al + Al8Cr
5 invariant reaction was observed at about 890 degrees C. Copyright (C
) 1996 Elsevier Science Limited.