It was found that the addition of In increased the diffusivity of Ag by up to 60 times:

D (cm2/s) = 4.60 x 10-2 exp[-14.40(kcal/mol)/RT]

but made the electromigration parameter more negative, until it eventually became equal to zero.

J.Shi, S.Mei, H.B.Huntington: Journal of Applied Physics, 1987, 62[2], 451-5