Hot rolling workability, texture and grain boundary character distribution of B2-type FeAl, NiAl and CoTi intermetallic compounds

Hot-rolling workability, texture and grain boundary character distribution of B2-type FeAl, NiAl and CoTi intermetallic compounds were investigated as a function of alloy stoichiometry. All the FeAl (i.e., Fe-38Al,-43Al and-48Al, denoted by at.%), and stoichiometric NiAl and CoTi were successfully hot-rolled at 1273 K but off-stoichiometric NiAl (Ni-48Al and-52Al) and CoTi (Co-48Ti and-49Ti) failed. After hot-rolling, all the FeAl showed microstructures with recrystallized coarse grains while (stoichiometric) CoTi retained a deformed microstructure. Hot-rolled (stoichiometric) NiAl showed an intermediate microstructure between FeAl and CoTi. The hot-rolling and annealing textures of FeAl essentially consisted of {111} u v w . For NiAl and CoTi, {111} 110 and {111} 112 were prominent in the hot-rolling texture, respectively. Both the hot-rolled NiAl and CoTi showed fully-recrystallized microstructures by subsequent annealing, but the resultant recrystallization textures were similar to their hot-rolling textures. On the other hand, grain boundary character distributions of FeAl, NiAl and CoTi with fully-recrystallized microstructures were similar to one another and characterized by a high frequency of low angle boundaries (i.e. 1 boundaries). Based on these results, recrystallization and grain boundary structure of the B2-type ordered intermetallic compounds were briefly discussed. C 2005 Springer Science + Business Media, Inc.