Summary: GRAIN-BOUNDARY SEGREGATION IN Al±10%Mg
ALLOYS AT HOT WORKING TEMPERATURES
and J. B. ADAMS2
Department of Materials Science and Engineering, University of Illinois, Urbana, IL 61801, U.S.A.
Department of Chemical, Bio. and Materials, Arizona State University, Tempe, AZ 85287-6006,
(Received 7 July 1997; accepted 12 January 1998)
AbstractŠMonte-Carlo simulations are done to determine Mg enrichment at various grain-boundaries of
Al±10%Mg alloys at hot working temperatures. The interatomic potentials used in the simulations are
developed using the force-matching method. The Mg segregation levels at the grain-boundaries are found
to vary from 20% to 40%. The segregation enrichment dierences at dierent grain-boundary sites are
explained in terms of atomic size and local hydrostatic stress. The segregation level varies strongly with
 tilt boundaries from low to high angle while showing minimal variation with  twist boundaries.
Segregation levels are found to have some correlation with grain-boundary energy. The eect on grain-
boundary decohesion due to Mg segregation is found to be a modest (10±35%) reduction in fracture
energy compared to the fracture energy in pure Al. # 1998 Acta Metallurgica Inc.