THERMAL-STABILITY AND HYDROGEN ABSORPTION CHARACTERISTICS OF PALLADIUM-YTTRIUM NANOALLOYS

Nanostructured alloys consisting of 10, 20 and 30 at.% Y in Pd were sy nthesized by high-energy ball-milling to determine the thermal stabili ty and hydriding behavior of different alloy compositions. Adding 10 a t.% Y to the Pd resulted in a nanoalloy that was stable against grain growth to above 400 degrees C, as compared to 200 degrees C for ball-m illed pure Pd. Adding 20 and 30 at.% Y resulted in a supersaturated so lution of Y in Pd and in the Pd3Y intermetallic phase, respectively. B oth the supersaturated solution and the intermetallic phase exhibited stability against grain growth to above 400 degrees C and interesting phase segregation behavior in heat treatment. In addition to stabilizi ng against grain growth, doping the Pd with Y also suppressed the alph a --> beta phase transition. Copyright (C) 1996 Acta Metallurgica Inc.