Nanoporous metallic structures by de-alloying bulk glass forming Zr-based alloys. (July 2018) - Mihaylov, L.
Abstract: Nanoporous structures have been produced by selective chemical dissolution of two multicomponent bulk glass-forming alloys with a supposed proper content of the more noble metals - Zr65 Ni30 Pd5 and Zr55 Ni30 Al10 Pd5 . The Al-containing alloy reveals open three-dimensional pores, while the selective dissolution of the Al-free ternary alloy results in larger surface pores and a number of disconnected ligaments. The average width of the ligaments, composed of 3–5 nm nanocrystals, is about 50 nm and the mean pore size for the de-alloyed quaternary alloy is 90 nm. The effect of Al on the ligament morphology and pore size is analyzed. Highlights: Nanoporous structures were obtained by selective dissolution of two glassy Zr alloys. Ligaments are composed of 3–5 nm Pd and Zrx Ni (x = 1, 2) nanocrystals. Primary glassy alloy composition has substantial influence on the porous structure. The effect of Al on the final microstructure of the porous material is analyzed. Better assembled 3D ligament structure is formed in the Al-containing Zr alloy.