鐵－鈀－銀合金之磁性相微結構與磁特性

Magnetic Structure and Magnetic Property of Fe-Pd-Ag Alloys

10.29948/JAE.200804.0004

林英志(Yin-Chih Lin)；李驊登(Hwa-Teng Lee)；林建鋒(Chien-Feng Lin)

鐵－鈀－銀合金 ； TEM與X-ray繞射 ； DSC ； 中間相L1(下标 m)微結構 ； Fe-Pd-Ag alloys ； TEM and X-ray diffraction ； DSC ； Intermediate L1(subscript m) structure

先進工程學刊

3卷2期（2008 / 04 / 01）

123 - 128

繁體中文

本研究論文主要利用穿透式電子顯微鏡(TEM)，X-ray繞射儀，調幅式示差掃描量熱計(DSC)，與超導量子干涉磁化儀(SQUID)，探討鐵－30鈀－4銀磁性合金固溶處理，與固溶處理後再經400-500℃，時效於各種不同時間之磁性相微結構與磁特性關係，TEM、X-ray繞射與DSC實驗結果證實，此合金固溶與時效處理後，在fcc→L10麻田散鐵相變態間，存在一中間相，此中間相為L1(下标 m)單斜晶結構，其晶格常數為a=3.208 Å，b=3.696 Å，c=3.127 Å，及β=91.997°，此中間相可能為一種適性相麻田散鐵。 超導量子干涉磁化儀之磁性量測結果顯示，固溶處理試樣，其ZFC與FC之磁化曲線並不聚合，一直到室溫T(下標R)=300K，當試樣固溶處理，再經500℃/100小時之時效處理後，則其ZFC與FC之磁化曲線呈現鋸齒狀(serrated)，此現象表示有兩種磁性相，存在時效處理之試樣內部，此兩種磁性相包括單斜晶L1(下标 m)與序化型正方晶L10微結構，這兩種磁性相具有不同之磁異向性(magnetic anisotropy)。

This investigation reports on TEM, X-ray diffraction, DSC, and SQUID magnetometer study of magnetic structures formed in Fe-30Pd-4Ag alloys solution treated and then thermally aged at 400-500℃ for various times. The results reveal that an intermediate structure appears between the fcc→L10 martensitic transformation. The intermediate phase, denoted L1(subscript m,) has a monoclinic structure with lattice parameters of a=3.208 Å, b=3.696 Å, c=3.127 Å, and β=91.997°, which indicates that the monoclinic structure is possibly adaptive martensite, as confirmed by TEM, X-ray diffraction, and DSC. The SQUID test shows that the ZFC and FC curves of the ST specimen do not coalesce until they reach room temperature at T(subscript R)=300 K. The serrated ZFC and FC curves of the specimen aged at 500℃ for 100 h indicate that two phases exist in the aged specimen. The two phases are comprised of monoclinic L1(subscript m) phase and tetragonal ordered L10 structure, which have differing magnetic anisotropy.