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研究生:施智超
研究生(外文):Jhy-Chau Shih
論文名稱:RT2材料的磁伸縮與磁性研究(R=Tb,Dy;T=Fe,Be,Mn,Al)
論文名稱(外文):Magnetostriction and magnetic properties of RT2 (R=Tb, Dy; T=Fe, Be, Mn, Al)
指導教授:金重勳金重勳引用關係
指導教授(外文):Tsung-Shune Chin
學位類別:博士
校院名稱:國立清華大學
系所名稱:材料科學工程學系
學門:工程學門
學類:材料工程學類
論文種類:學術論文
論文出版年:2002
畢業學年度:90
語文別:中文
論文頁數:128
中文關鍵詞:磁伸縮稀土-過渡元素磁性微機電系統磁歪鋱鐵鋱鏑鐵
外文關鍵詞:magnetostrictionmagnetostrictivemagneticMEMSTerfenolTerfenol-DTbFe2Tb-Dy-Fe
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磁伸縮材料能將電磁能與機械能互相轉換,在微機電及感測元件的應用上極具潛力,因此引起廣泛的研究與討論。本文針對Tb0.3Dy0.7(Fe, Be)2塊材、Tb(Fe, Mn, Al)2塊材、Tb0.3Dy0.7(Fe, Mn, Al)2薄帶和Tb-Fe薄膜的磁性及磁伸縮應變加以研究。
利用電弧熔鍊的方式將不同比例的鋱、鈹、錳、鋁、鏑及鐵,熔鍊形成Tb0.3Dy0.7(Fe1-xBex)2塊材(x= 0~0.1)、Tb(Fe0.9MnxAl0.1-x)2塊材(x= 0~0.1),結果顯示添加少量的鈹取代Tb0.3Dy0.7Fe2中的鐵,對硬度、磁伸縮係數l、動態應變係數最大值d33max和相對應的磁場Hd33max都有正面的作用,最佳條件的樣品鈹含量為6.67原子百分比,當外加磁場為0.5 kOe時,磁伸縮為原來未添加鈹的6倍;d33max從97×10-9 Oe-1提升到256×10-9 Oe-1,為原來的2.5倍;Hd33max從1.62 kOe降低為0.62 kOe。同時添加少量的錳和鋁取代TbFe2中的鐵,對硬度、小磁場中的l、d33max和Hd33max都能有所改善,最佳條件的樣品錳含量為2.67原子百分比,當外加磁場為1 kOe時,磁伸縮為TbFe2的11倍;d33max從210×10-9 Oe-1提升到360×10-9 Oe-1;Hd33max從1.75 kOe降低為0.56 kOe。
Tb0.3Dy0.7(Fe0.9Mnx Al0.1-x)2薄帶是運用單輪熔液旋淬法製作,銅輪轉速介於30到40 m/s之間。薄帶Mn-01與Mn-05的樣品有立方型Laves phase部分結晶,而樣品Mn-07與Mn-09的樣品則有富稀土相析出。由磁伸縮係數的量測結果得知,薄帶的磁伸縮應變不適合用應變規來量測。
利用直流磁控濺鍍的方式,改變不同濺鍍參數製作Tb-Fe薄膜。並藉由磁力顯微鏡,觀測不同膜厚、基板溫度及濺鍍功率的薄膜表面磁結構。此外,施加大小不一的張應力於薄膜上,並觀察表面磁結構的變化。最後再運用微磁學的理論,討論所觀測到的磁區結構,並計算出樣品的單位面積磁壁能及交換常數。
The magnetostrictive materials are potential for MEMS and device applications, because of their capability to convert magnetic energy to mechanical energy. This thesis reports the magnetostriction and magnetic properties of Tb0.3Dy0.7(Fe,Be)2 bulks, Tb(Fe,Mn,Al)2 bulks, Tb0.3Dy0.7(Fe,Mn,Al)2 ribbons and Tb-Fe thin films.
Ingots of Tb0.3Dy0.7(Fe1-xBex)2 (x= 0~0.1) and Tb(Fe0.9MnxAl0.1-x)2 (x= 0~0.1) alloys were prepared from 99.9% purity Tb, Dy, Fe, Be, Mn and Al by acr-melting in a cold copper crucible under an argon atmosphere. The results indicate that the addition of beryllium improves hardness, magnetostriction l, dynamic strain coefficient d33max and lowers the corresponding field Hd33max for Tb0.3Dy0.7(Fe1-xBex)2 alloys. The optimum specimen of Be-series is that 6.67 at.% Be, and the magnetostriction is five times larger then unmodified under a magnetic field 0.5 kOe. The d33max value of the optimum specimen (256×10-9 Oe-1) is 1.5 times larger then that of original specimen (97×10-9 Oe-1), and Hd33max is improved from 1.62 kOe to 0.62 kOe.
The modification by both Mn and Al improves hardness, l at low field, d33max and lowers Hd33max for Tb(Fe0.9MnxAl0.1-x)2 alloys. The x=0.04 (2.67 at.% Mn) alloy is the optimum one in Mn-Al-series, and the magnetostriction is ten times larger then that unmodified under a magnetic field 1 kOe. The d33max value of the optimum specimen increases from 210×10-9 Oe-1 to 360×10-9 Oe-1, and Hd33max is improved from 1.75 kOe to 0.56 kOe.
Tb0.3Dy0.7(Fe0.9MnxAl0.1-x)2 ribbons were prepared by melt-spinning method. All of the specimens contain partial crystalline of Laves phase or rare earth rich phase, even the wheel speed achieved 40 m/s. The results indicate that strain gauge method is not suitable for measuring magnetostriction of ribbons.
Tb-Fe thin films were prepared by DC magnetron sputtering from an alloy-target with different sputtering parameters, which included substrate temperature, sputtering time and power. The magnetic force microscopy was used to observe the domain structure of the samples. The domain structure versus strain effect was studied. From the domain observe, we calculated the domain wall energy per unit area and exchange const.
摘要-----------------------------------------------------------I
英文摘要------------------------------------------------------II
致謝---------------------------------------------------------III
目錄----------------------------------------------------------IV
表目錄--------------------------------------------------------VI
圖目錄-------------------------------------------------------VII
符號對照表-----------------------------------------------------X
第一章 序言-------------------------------------------------1
§1-1磁伸縮材料的重要性----------------------------------------1
§1-2磁伸縮材料具體要求----------------------------------------2
§1-3本文選題思路----------------------------------------------3
§1-4主要內容--------------------------------------------------5
第二章 文獻回顧及理論---------------------------------------7
§2-1磁伸縮材料歷史概述及發展趨勢------------------------------7
§2-2稀土與鐵族過渡元素基本磁學------------------------------13
§2-3磁伸縮理論-----------------------------------------------17
§2-4 RFe2的結構----------------------------------------------21
§2-5磁伸縮量測原理------------------------------------------22
2-5-1應變規--------------------------------------------------22
2-5-2光學系統-------------------------------------------------24
§2-6磁力顯微鏡-----------------------------------------------26
§2-7振動樣品磁量儀-------------------------------------------29
第三章 實驗內容及方法--------------------------------------43
§3-1實驗流程圖-----------------------------------------------43
3-1-1 磁伸縮塊材----------------------------------------------43
3-1-2 Tb0.3Dy0.7(Fe0.9MnxAl0.1-x)2薄帶------------------------44
3-1-3 磁伸縮Tb-Fe薄膜-----------------------------------------45
§3-2樣品準備------------------------------------------------ 46
3-2-1 製作磁伸縮塊材------------------------------------------46
3-2-2 製備Tb0.3Dy0.7(Fe0.9MnxAl0.1-x)2薄帶--------------------47
3-2-3 製備Tb-Fe薄膜-------------------------------------------48
§3-3檢測方法-------------------------------------------------50
3-3-1磁伸縮量測方法-------------------------------------------50
3-3-2磁力顯微鏡-----------------------------------------------51
3-3-3振動樣品磁量儀-------------------------------------------56
3-3-4 X光繞射儀---------------------------------------------- 56
3-3-5 熱分析儀------------------------------------------------57
3-3-5 硬度量測------------------------------------------------58
第四章 結果與討論------------------------------------------64
§4-1 鈹對Tb0.3Dy0.7Fe2塊材的影響-----------------------------64
4-1-1 XRD相鑑定-----------------------------------------------64
4-1-2 基本磁性質----------------------------------------------66
4-1-3 微結構--------------------------------------------------67
4-1-4 硬度量測------------------------------------------------68
4-1-5 磁伸縮量測----------------------------------------------69
§4-2 Tb(Fe0.9MnxAl0.1-x)2塊材磁性質研究----------------------72
4-2-1 XRD相鑑定-----------------------------------------------72
4-2-2 基本磁性質與硬度----------------------------------------73
4-2-3 磁伸縮量測----------------------------------------------74
§4-3 Tb0.3Dy0.7(Fe0.9MnxAl0.1-x)2薄帶------------------------76
§4-4 Tb-Fe薄膜磁區觀察---------------------------------------77
4-4-1 濺鍍參數與磁區觀測--------------------------------------77
4-4-2 圓點狀磁區結構模型--------------------------------------79
4-4-3 外加應力與磁區觀測--------------------------------------81
4-4-4 TbFe薄膜更進一步分析------------------------------------83
第五章 總結-----------------------------------------------119
第六章 參考文獻-------------------------------------------121
附錄一 SCI期刊論文著作列表-----------------------------------127
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