Structure and hardness of explosively loaded FeAl intermetallic alloys

The effect of the explosive loading at the 4.5-11.0 GPa shock pressure range and a subsequent heat treatment on the structure and hardness of FeAl intermetallic alloys were studied. As-cast FeAl intermetallic alloys were shock-wave deformed using various cylindrical explosive assemblies and type of explosives. It was found that the microhardness of explosively loaded FeAl intermetallic alloys increases with increasing applied pressure and is considerably higher than that of their as-cast and homogenized or hot-worked counterparts. The TEM examinations revealed many straight line dislocations with sharp jogs indicative of cross-slipping in explosively-loaded iron-rich intermetallics. In the regions of the highest dislocation density a tendency to formation a dislocation cell substructure in Fe-39,43 and 46Al was observed. Anneals of intermetallics explosively-loaded above 5.9 GPa lead to their primary recrystallization. The cracks in all the FeAl-based intermetallic specimens that were either explosively loaded at 5.9 and 11.0 GPa of the applied explosive pressure or contained the highest Al content (near-stoichiometric) were revealed. (C) 1997 Elsevier Science S.A.