摘要
用机械合金化方法研究了NdFe12 -xVxNδ 各向同性粉末的结构和永磁性能 .发现在 70 0～ 90 0℃退火机械合金化粉末时 ,除了钒含量x =1的样品在 75 0℃以下退火时 ,晶化不完全 ,有大量的α -Fe(V)相析出外 ,其余的样品在 70 0～ 90 0℃退火温度范围内都形成了Nd(Fe ,V) 12 相 .氮化后 ,体积膨胀约为 5 % ,居里温度提高 1 40～ 1 60℃ .NdFe12 -xVNδ 氮化物的居里温度为 469～ 485℃ .增加钒含量 ,NdFe12 -xVxNδ 内禀矫顽力增加 ,对x=2在 75 0℃退火后渗氮的样品矫顽力 iHc=870kA/m .机械合金化不同钒含量的NdFe12 -xVxNδ 氮化物样品矫顽力的差别可归因于不同钒含量样品晶化行为的差和氮化过程中相的稳定性 .
The structure and permanent magnetic properties of isotropic powders of NdFe 12-x V xN δ compounds were investigated by using mechanical alloying. It was found that heat treatment of asmilled powders at 700～900 ℃ resulted in the formation of Nd(Fe,V) 12 phase except for the sample with x=1, for which the crystallization was not complete and a large amount of α-Fe(V) was present at temperatures below 750 ℃. After nitrogenation, the volume expansion was about 5% and the Curie temperature enhancements were 140 ℃ to 160 ℃. In NdFe 12-x V xN δ the values of T c fall in the range 469～485 ℃. It has been found that the intrinsic coercivities strongly increased with increasing V content. The maximum coercivity of i H c=870 kA/m is achieved at 750 ℃ with x=2.00. The difference between the coercivities of the mechanical alloyed Nd(Fe,V) 12 N δ powders with different V content is attributed to their different crystallization behavior and phase stability during nitrogenation.
出处
《材料科学与工艺》
EI
CAS
CSCD
2000年第1期30-34,共5页
Materials Science and Technology
基金
国家自然科学基金!资助项目 (594 710 2 2 )
关键词
机械合金化
磁学性能
结构
永磁性能
磁合金
mechanical alloying
ThMn 12 -type structure compound
magnetic property
