材料的结构决定其性能。多元镍基或钴基合金在镀态时通常呈非晶态结构,在热处理条件下将发生结构的变化,进而引起性能的变化。主要研究了以下两方面的内容:(1)以柠檬酸钠为络合剂、硼酸为缓冲剂在弱碱性介质中化学沉积Ni_(68.0)Fe_(10.5...材料的结构决定其性能。多元镍基或钴基合金在镀态时通常呈非晶态结构,在热处理条件下将发生结构的变化,进而引起性能的变化。主要研究了以下两方面的内容:(1)以柠檬酸钠为络合剂、硼酸为缓冲剂在弱碱性介质中化学沉积Ni_(68.0)Fe_(10.5)P_(21.5)。采用差示扫描量热(DSC)和X射线衍射(XRD)研究了Ni_(68)Fe_(10.5)P_(21.5)镀层的晶化行为,结果表明,非晶态的镀态镀层在370.0℃下热处理时出现Ni_3P相(I-4),495.0℃下晶化生成FeNi_3相(P_(m3m))。该镀层在镀态时呈圆形颗粒紧密堆积的结构。经过400℃热处理后,镀层晶化生成了许多排列均匀、粒径小于10nm的纳米颗粒;而经过500℃热处理的镀层生成了粒径为20～40 nm的纳米颗粒;经过600℃热处理后晶粒进一步变大,粒径达0.1～0.3μm。在500℃下热处理镀层,随着热处理时间增加,镀层的晶化越完全。据此,通过控制在500℃下热处理时间制备了纳米复合的NiFeP合金。Ni_(68.0)Fe_(10.5)P_(21.5)合金的磁参数(饱和磁化强度、剩余磁化强度和矫顽力)均随着热处理温度的升高而提高;经500℃处理后合金的磁参数达到最大;热处理温度太高,磁参数反而有所降低。发现Ni_(68.0)Fe_(10.5)P_(21.5)合金在500℃下热处理40min时磁参数达到最大;若继续延长热处理时间,则合金的磁参数反而逐渐降低。实验证实,纳米复合的NiFeP合金磁性能最优。(2)以硼氢化钾为还原剂(KBH_4)、乙二胺为稳定剂化学沉积Co-Fe-B。采用差示扫描量热(DSC)和X射线衍射(XRD)研究了Co-Fe-B镀层的晶化行为,结果显示,非晶态的镀态镀层在464.9℃下热处理时晶化为Co_3B and CoFe相。分别采用高分辨扫描电镜和振动样品磁强计研究了热处理温度对镀层微观结构和磁性能的影响,结果表明,随着热处理温度增加到450℃,镀层的饱和磁化强度和矫顽力都增加,并在450℃达到最大值,进一步增加热处理温度,则饱和磁化强度和矫顽力都下降。在500℃下热处理镀层晶化生成大量直径约20 nm的颗粒,该合金具有理想的磁性能可作软磁膜材料。展开更多
We review our works that focus on the microwave magnetic properties of metallic, ferrite and granular thin films. Soft magnetic material with large permeability and low energy loss in the GHz range is a challenge for ...We review our works that focus on the microwave magnetic properties of metallic, ferrite and granular thin films. Soft magnetic material with large permeability and low energy loss in the GHz range is a challenge for the inforcom technologies. GHz magnetic properties of the soft magnetic thin films with in-plane anisotropy were investigated. It is found that several hundreds of permeability at the GHz frequency was achieved for Col00_xZrx and Co90Nbl0 metallic thin films because of their high satu- ration magnetization, and an adjustable resonance frequency from 1.3 to 4.9 GHz was obtained. Compared with the metallic thin films, the weaker saturation magnetization of Ni-Zn ferrite thin films results in several tens of permeability at the GHz frequency, but the larger resistivity of the ferrite prepared in situ without any heating treatments has lower energy loss. In order to obtain materials with large permeability and low energy loss in the GHz range, the [CoFe-NiZn ferrite] composite granular thin films were investigated, where the advantage of higher saturation magnetization for the metallic alloy and the high resis- tivity as well as high saturation magnetization for the ferrite results in a good GHz magnetic performance.展开更多
文摘材料的结构决定其性能。多元镍基或钴基合金在镀态时通常呈非晶态结构,在热处理条件下将发生结构的变化,进而引起性能的变化。主要研究了以下两方面的内容:(1)以柠檬酸钠为络合剂、硼酸为缓冲剂在弱碱性介质中化学沉积Ni_(68.0)Fe_(10.5)P_(21.5)。采用差示扫描量热(DSC)和X射线衍射(XRD)研究了Ni_(68)Fe_(10.5)P_(21.5)镀层的晶化行为,结果表明,非晶态的镀态镀层在370.0℃下热处理时出现Ni_3P相(I-4),495.0℃下晶化生成FeNi_3相(P_(m3m))。该镀层在镀态时呈圆形颗粒紧密堆积的结构。经过400℃热处理后,镀层晶化生成了许多排列均匀、粒径小于10nm的纳米颗粒;而经过500℃热处理的镀层生成了粒径为20～40 nm的纳米颗粒;经过600℃热处理后晶粒进一步变大,粒径达0.1～0.3μm。在500℃下热处理镀层,随着热处理时间增加,镀层的晶化越完全。据此,通过控制在500℃下热处理时间制备了纳米复合的NiFeP合金。Ni_(68.0)Fe_(10.5)P_(21.5)合金的磁参数(饱和磁化强度、剩余磁化强度和矫顽力)均随着热处理温度的升高而提高;经500℃处理后合金的磁参数达到最大;热处理温度太高,磁参数反而有所降低。发现Ni_(68.0)Fe_(10.5)P_(21.5)合金在500℃下热处理40min时磁参数达到最大;若继续延长热处理时间,则合金的磁参数反而逐渐降低。实验证实,纳米复合的NiFeP合金磁性能最优。(2)以硼氢化钾为还原剂(KBH_4)、乙二胺为稳定剂化学沉积Co-Fe-B。采用差示扫描量热(DSC)和X射线衍射(XRD)研究了Co-Fe-B镀层的晶化行为,结果显示,非晶态的镀态镀层在464.9℃下热处理时晶化为Co_3B and CoFe相。分别采用高分辨扫描电镜和振动样品磁强计研究了热处理温度对镀层微观结构和磁性能的影响,结果表明,随着热处理温度增加到450℃,镀层的饱和磁化强度和矫顽力都增加,并在450℃达到最大值,进一步增加热处理温度,则饱和磁化强度和矫顽力都下降。在500℃下热处理镀层晶化生成大量直径约20 nm的颗粒,该合金具有理想的磁性能可作软磁膜材料。
基金supported by the National Natural Science Foundation of China (Grant No. 11034004)National Science Fund for Distinguished Young Scholars (Grant No. 50925103)+1 种基金Key Grant Project of Chinese Ministry of Education (Grant No. 309027)the Fundamental Research Funds for the Central Universities (Grant No. lzujbky-2010-219)
文摘We review our works that focus on the microwave magnetic properties of metallic, ferrite and granular thin films. Soft magnetic material with large permeability and low energy loss in the GHz range is a challenge for the inforcom technologies. GHz magnetic properties of the soft magnetic thin films with in-plane anisotropy were investigated. It is found that several hundreds of permeability at the GHz frequency was achieved for Col00_xZrx and Co90Nbl0 metallic thin films because of their high satu- ration magnetization, and an adjustable resonance frequency from 1.3 to 4.9 GHz was obtained. Compared with the metallic thin films, the weaker saturation magnetization of Ni-Zn ferrite thin films results in several tens of permeability at the GHz frequency, but the larger resistivity of the ferrite prepared in situ without any heating treatments has lower energy loss. In order to obtain materials with large permeability and low energy loss in the GHz range, the [CoFe-NiZn ferrite] composite granular thin films were investigated, where the advantage of higher saturation magnetization for the metallic alloy and the high resis- tivity as well as high saturation magnetization for the ferrite results in a good GHz magnetic performance.
