The internal friction as a function of temperature and the giant magnetores
istance for varying magnetic field have been measured on Cu90Co10 ribbons o
btained by planar flow casting with different quenching rate. The results a
re discussed considering the presence of quenched-in Co precipitates in the
Cu matrix of the as-cast ribbons and different levels of dispersion of Co
in the Cu matrix in the two cases. (C) 1999 Acta Metallurgica Inc.