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本文研究了热处理工艺、合金成份、磁场、温度及不同应力振幅等对Fe-Cr、Fe-Cr-Al铁磁性合金阻尼(内耗)特性的影响。内耗和阻尼特性是用弯曲共振法(共振频率1500～1700Hz)和大应力扭摆仪(倒摆,振动频率20Hz左右)测得的。研究结果表明: 1. Fe-Cr、Fe-Cr-Al合金在磁场40～50Oe区间出现内耗峰。内耗峰的位置及峰值同合金成分及退火温度有关。磁场超过40～50Oe,合金的内耗明显下降,直至最低值,此时合金已磁化饱和,即其磁机械滞后效应完全消失。 2. 温升从20～350℃时,合金由于磁机械滞后效应引起的内耗略有下降趋势,高于350℃时,合金的内耗开始明显下降,并急剧降到最低值。 3. 阻尼比(内耗)随应力振幅(τ_(max))增加而明显增高,并达到最大值;应力振幅继续增加,合金阻尼比开始下降或在一定应力范围内维持不变,随后又缓慢降低。合金的成份和热处理工艺对内耗-应力(Q~(-1)～τ_(max))曲线特性影响尤为明显。 4. Fe-Cr-Al合金内耗-应力曲线出现的峰值随外磁场增加而下降,当合金磁化饱和时,内耗-应力曲线的内耗峰完全消失,即合金由于磁机械滞后效应所引起内耗已不存在,此时合金的阻尼性能最低。
The effects of heat treatment process, alloy composition, magnetic field, temperature and different stress amplitudes on the damping (internal friction) properties of Fe-Cr and Fe-Cr-Al ferromagnetic alloys were investigated. Internal friction and damping characteristics are measured by bending resonance method (resonance frequency 1500 ~ 1700Hz) and large stress swinging instrument (inverted, vibration frequency 20Hz or so). The results show that: 1. Fe-Cr, Fe-Cr-Al alloy in the magnetic field 40 ~ 50Oe range of internal friction peak. The location and peak of the internal friction peak are related to the alloy composition and the annealing temperature. Magnetic field more than 40 ~ 50Oe, the alloy’s internal friction decreased significantly until the lowest value, when the alloy has magnetization saturation, that is, its mechanical and mechanical hysteresis completely disappeared. When the temperature rises from 20 ~ 350 ℃, the internal friction caused by the magnetomechanical hysteresis has a slight downward trend. When the temperature rises above 350 ℃, the internal friction of the alloy begins to drop obviously and sharply drops to the lowest value. The damping ratio (internal friction) increases with the increase of the stress amplitude (τ max) and reaches the maximum value. The stress amplitude continues to increase, the damping ratio of the alloy begins to decrease or remains unchanged within a certain stress range, and then slowly decreases . The composition of the alloy and heat treatment process on the internal stress - stress (Q ~ (-1) ~ τ_ (max)) curve characteristics particularly evident. The peak value of the internal friction loss-stress curve of Fe-Cr-Al alloy decreases with the increase of external magnetic field. When the alloy magnetization is saturated, the internal friction peak of the internal friction loss curve completely disappears, ie the internal friction caused by the magnetomechanical hysteresis of the alloy is no longer Exists, at this moment the damping property of the alloy is the lowest.