文档介绍:Increasing Si content in Ni5() alloy is in favor of
increasing the onset secondary crystallization temperatures, ��2 , the crystallized interval temperature, ∆��, and the maximum operation temperature, �𝑚𝑎�. For samples heating-cooling cycled at 510–680°C, with �𝑎increasing, the room-temperature �𝑖decreases but high-temperature one increases, leading to an
improvement of its thermal stability extended from room temperature up to 680°C. The optimum ic softness at elevated temperature is observed for the sample heating-cooling cycled at 640°C. The initial permeability above 1000 at 10 KHz can keep up to 600°C.
Keywords: nanocrystalline alloy, initial permeability, saturation ostriction, exchange-coupling interaction
目 录
第一章绪论································································1 引言···································································1
纳米晶合金研究现状 ·················································· 2
纳米晶合金的起源与发展········································2
高温纳米晶合金软磁材料发展瓶颈及改善方法······················ 5
纳米晶软磁合金的化学成分及其作用······························ 6
纳米晶软磁合金的交换耦合作用··········································7
Herzer 有效各向异性模型 7
Hernando 有效各向异性模型 8
Suzuki 有效各向异性模型 10
本文研究的意义及主要内容············································· 11
本文的目的和意义············································· 11
本文的主要内容···············································12
第二章 实验方法··························································14
样品制备·····························································14
非晶条带制备··················································14
纳米晶合金样品制备············································15
实验分析技术··························································17
差示扫描量热法(DSC) 17
X 射线分析衍射分析技术(XRD) 19
高温磁性测量··················································22
透射电子显微镜分析技术(TEM) 23
饱和磁致伸缩系数测量·······························