High-Frequency Characteristic Test and Loss Calculation of TbDyFe Alloy Under Variable Temperature

The dynamic magnetic characteristic curves of TbDyFe alloy (TbxDy
_1−x
Fe
_1.9–2.0
,
$0.27 \leq x \leq 0.3$
) under varying temperatures at different high-frequency excitation conditions were measured. The results show that when the excitation amplitude and frequency keep constants, the dynamic hysteresis loop, the permeability, and the magnetic energy loss all vary with the increase in temperature (from 10 °C to 80 °C). Their trends of temperature dependence are analyzed in detail. Based on the Bertotti loss separation method and experimental data, a magnetic energy loss calculation model for TbDyFe alloy under variable temperature conditions is proposed. The model considers the influence of high-frequency hysteresis characteristics and skin effect. It introduces temperature-related terms to modify the loss coefficients. The calculation results are compared with the experimental ones at different temperatures. It shows that this calculation method can accurately calculate the magnetic energy losses under variable temperature at higher frequencies (1–20 kHz). This research can provide an experimental and theoretical support for high-frequency engineering application of magnetostrictive materials.