The interaction between Terfenol-D (Tb(x)Dy(1-x)Fey (0.27 <= x <= 0.30, y <= 2)) melts and quartz crucibles has been studied. A rare earth silicide was formed next to a rare earth oxide on SiO2 substrate and a surface layer of rare earth oxide appeared on top of the silicide layer. The reaction was controlled by diffusion with an activation energy E-a = 1.59 eV. The effect of Si contamination on the magneto-elastic property was evaluated. Maximum mangnetostriction of Terfenol-D decreased by 300 ppm while Si addition increased up to 1.0 at.%. (c) 2005 Elsevier B.V. All rights reserved.