Quantitative prediction of aging effects in plated wires

Aging effects induced by magnetic annealing of plated wires were studied by measurement of skew. The annealing was done in a magnetic field parallel to the hard axis, which rotated the film magnetization to approximately 45°. The data are described by one fixed and two annealable components of anisotropy. Based on data obtained between 100 and 200°C an aging curve was constructed for 50°C which shows that as a conservative worst case the plated wire will have 31 mOe ( ) of skew after 10 years. End-of-life derating design procedures can accommodate this amount of skew. Generally good agreement with theoretical relationships was observed.