摘要
用粉末冶金法研制出高居里温度的Nd-Co-Fe-Ga-B永磁材料。Nd-Fe-B永磁材料居里温度从312℃提高到450～500℃;内禀矫顽力_iH_c可达716～955kA/m;最大磁能积(BH)max=223～262kJ/m^3。用穆斯堡尔效应等方法研究Nd_(16)Co_(16)Fe_(61-x)Ga_xB_7样品的结果表明:在x=2时,Ga原子主要占据j_2晶位;x>2时,除j_2外,K_2、j_1、K_1三个晶位均有一定的占据几率。X射线衍射实验证实,此合金在x=2处,四方相的点阵常数a值最大,而c值随x的增大(由1到7)呈线性增加。从磁测量结果发现,在x=2处,内禀矫顽力出现峰值。
The Curie temperature of the permanent magnet Nd-Fe-B is only 312℃, so its applications are restricted. In order to expand its applications, we prepared the title materials by powder metallurgy.Nd_(10)Co_(16)Fe_(61-x) Ga_xB_7(x=0, 1,2,4 and 7) permanent magnets were studied by Mossbauer effect, magnetic measurement and X-ray diffraction experiment. The main results are shown as follows. 1. Adding a certain amount of Co and Ga to Nd-Fe-B alloys, the Curie temperature of the magnets amounts to 450℃ to 500°, the cocrcivity 718.5 KA/m to 938.SKA/m, The magnet with x=2 has best magnetic properties.2. The lattice parameters of the magnets were affected slightly by replacing part of iron with Co and Ga atoms.3. The Mossbauer effects show that Ga atoms mainly occupy j_2 sites in tetragonal phase when x=2, and also K_2 sites when x>2.In the range from x=0 to x=2 the coercivity of samples increases with the increase of Ga content, and there exist a maximum value at x=2. We can conclude that the magnet with x=2 has the most perfect magnetic properties.
出处
《中国稀土学报》
CAS
CSCD
北大核心
1989年第3期36-40,共5页
Journal of the Chinese Society of Rare Earths
