Cobalt Content Effect on the Magnetic Properties of Ni 50-x Co x Mn 35.5 In 14.5 Annealed Ribbons.

We present a study of the annealing effect and its influence on magnetic and structural properties for a series of Heusler alloys Ni50-xCoxMn35.5In14.5 (x=0,3,5) prepared in ribbon form. We studied the morphology and composition using scanning electron microscopy (SEM) equipped with an X-ray microanalyzer (EDX). The magnetic properties were determined by two methods: electron magnetic resonance (EMR) and vibrating sample magetometer (VSM). We found that cobalt content in the annealed samples reveals an additional magnetic phase transition at lower temperatures.