Effect of adhesion of metals on deterioration of Pd and Pd alloy membranes

Stainless-steel, Ni, Cr and Fe particles were adhered on Pd and Pd alloy membranes in order to investigate an effect of alloying of such metal components and membranes to the membrane performance. The adhesion of metal particles to Pd and Pd alloy membranes were evaluated through the thermal treatment. Cracks were observed along the metal particles on Pd and Pd-Ag membranes by alloying between the membranes and metal particles. For Ni and Cr, the crack formation was caused by the Kirkendall effect. For Fe, that should be attributed to the Kirkendall effect or the phase transition of Pd-Fe alloys. In contrast, it was found that Pd-Ni and Pd-Fe binary alloy membranes prevented the crack formation because alloying of Pd with appropriate metals could control the interdiffusion between Pd alloy membranes and adhered metal particles.