MICROSTRUCTURAL INFLUENCE ON MAGNETIC-PROPERTIES AND GIANT MAGNETORESISTANCE OF MELT-SPUN GOLD-COBALT

Microstructural influence on saturation magnetization, remanence, coercivity and giant magnetoresistance (GMR) of melt-spun Au 1−x -Co x , (x = 0.65 and 0.284) ribbons in the as-quenched state and subsequently annealed at 480 °C has been investigated using analytical transmission electron microscopy. The evolution of the magnetic data with annealing time was found to be determined by the sequence of the formation of Co precipitates, their volume fraction, their particle size distribution and their morphology. GMR behavior was only measured for Au 73.6 Co 28.4 and is clearly caused by a lamellar eutectic with a structure similar to multilayers.