| Summary: | We present an exhaustive study of the magnetoelastic properties of 24 strips with different rectangular dimensions, cut from a long ribbon of Metglas<sup>®</sup> 2826MB3. The strips have a length-to-width ratio <i>R = L/w</i> ranging from 2 to over 20. Significant variations of the apparent saturation Young’s modulus and the <i>ΔE</i> effect with strip geometry, changing from 160 GPa and 4% for <i>L</i> = 10 mm, <i>w</i> = 5 mm and <i>R</i> = 2, to 164 GPa and 9.6% for <i>L</i> = 35 mm, <i>w</i> = 1.7 mm and <i>R</i> = 20.6, have been observed. In order to obtain the highest values of the <i>ΔE</i> effect, the magnetomechanical coupling coefficient, <i>k</i>, and the quality factor of the resonance, <i>Q</i>, a value <i>R</i> > 14 is needed. The effective anisotropy field <i>H<sub>k</sub><sup>*</sup></i>, taken as the minimum of the <i>E(H)</i> curve, and its width <i>ΔH</i>, are not as strongly influenced by the <i>R</i> value, and a value of <i>R</i> > 7 is enough to reach the lowest value. From our measurements we infer that the formerly predicted value of <i>R</i> > 5 needed for a good magnetic and magnetoelastic response of the material must be actually regarded as the lowest limit for this parameter. In fact, we show that the demagnetizing factor <i>N</i>, rather than the length-to-width ratio <i>R</i>, is the parameter that governs the magnetoelastic performance of these strips.
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