Influence of processing conditions on the microstructure and permeability of BCC V–Ni membranes

V–Ni–Ti multi-phase alloy membranes for hydrogen purification

“…A previous publication from this group reported on the single-phase BCC microstructure of the V 85 Ni 15 alloy [4]. Partial substitution of V by Ti, however, can result in a multi-phase microstructure.…”

“…Vanadium has received most attention because of its ability to maintain the BCC structure over a wider compositional range than Ta or Nb. The best known BCC alloys for membrane applications are vanadium-based solid solutions containing Ni [3][4][5][6], and Al, Ag, Pd, Fe, Mn, Co and Cu [7][8][9][10][11].…”

Non-Pd BCC alloy membranes for industrial hydrogen separation

“…The number of defects at which H 2 formation may occur can be reduced by annealing [144]. Annealing also increases grain size, with grains of greater than 250 m forming in bulk V-Ni after annealing, and this can lead to embrittlement through impurity segregation as will be discussed below.…”

“…For example, Song et al [144] showed that grains in a BCC V-Ni membrane alloy can grow to >250 m, far greater than the desired thickness of a membrane (Fig. 2).…”

“…Sectioning of homogenized ingots has been applied for the preparation of laboratory-scale membranes suitable for the examination of compositional [46,58,193] or microstructural [144] effects. The shortcomings of this approach are the limited size of the resulting membranes, the high labour intensity and the thickness of the resulting membranes (several hundred m).…”