Wetting of molybdenum grain boundaries by nickel: Effect of the boundary structure and energy

The structural effect of the penetration of nickel along symmetrical [101] tilt grain boundaries (GBs) in two different molybdenum bicrystals is inves tigated. The selection of GBs (Sigma = 3{121} and Sigma=11{323}) is governe d by their different energy so that a different penetration behaviour is ex pected. The temperature of treatment is 1350 degrees C, i.e, above the eute ctic temperature. The analysis of the Mo-Ni phase formed on the surface of the bicrystal, the concentration profile along the GB and the identificatio n of the nanophases present at the GB is performed by using several experim ental techniques from microscopic to nanoscopic scales. Important differenc es in the penetration of nickel are found for the two investigated GBs. (C) 2000 Published by Elsevier Science Ltd on behalf of Acta Metallurgica Inc.