多孔碳化硅陶瓷上镍铁氧体涂层的制备与性能

Preparation and Properties of the Nickel Ferrite Coated on Porous Silicon Carbide Ceramic

以Ni(NO3)2和Fe(NO3)3、丙烯酰胺、N,N′-亚甲基双丙烯酰胺为原料,采用高分子凝胶法在多孔碳化硅陶瓷表面包覆了镍铁氧体涂层.着重研究了包覆涂层的表面形貌、复合材料的晶相及电磁性能.结果表明,当煅烧温度为600℃时,在多孔陶瓷表面有立方晶系尖晶石结构的NiFe2O4晶相生成.随着煅烧温度的升高,多孔陶瓷表面形成的镍铁氧体晶体晶型趋向完整.涂层完整、致密、均匀.多孔碳化硅陶瓷为介电损耗材料,孔径为1.3mm的多孔碳化硅陶瓷基体的电磁性能优于孔径为1.0mm的多孔碳化硅陶瓷.包覆镍铁氧体涂层的多孔碳化硅陶瓷表现出较好的磁损耗特性,复磁导率的虚部最大值可达0.4.

The nickel ferrite coated on porous SiC ceramic was prepared using polyacrylamide gel method with iron nitrate [Fe（NO3）3.9H2O], nickel nitrate [Ni（NO3）2-6H2O], acrylamide and N, NCmethylenediacrylamide as raw materials. The morphology, structural characteristics and electromagnetic properties of the composite were analyzed. The results indicated that a pure spinel structure of NiFe2O4 formed on the porous ceramic at 600℃. The NiFe2O4 was better crystallized with the increase of annealing temperature. The nickel ferrite coating on porous SiC ceramic was uniform, continuous and consistent. The porous SiC ceramic belonged to a kind of dielectric loss material. And the porous SiC ceramic matrix with 1.3 mm pore diameter exhibited higher electromagnetic property compared with that with 1.0 mm pore diameter. The porous SiC ceramic coated with NiFe2O4 showed a better magnetic loss property. Its maximum value of the imaginary part of permeability was 0.4.