Fabrication of an in situ Al–Nb metal matrix composite by constrained shear strain and its emission efficiency in a glow discharge

Constrained shear strain with subsequent annealing was used to fabricate an in situ Al–Nb metal matrix composite with the fraction of an Al$_3$Nb intermetallic phase of 25 at%. The composite microstructure was studied. The emission efficiency of the Al–Nb composite samples in a glow discharge was determined, along with those of aluminum and niobium as cold cathodes. The difference in the glow current was analyzed by fixed voltages at cathodes made of the studied materials.