烧结温度对超低损耗锰锌铁氧体性能的影响

摘要

MnZn power ferrites with same composition and addition were prepared sintering at 1360℃, 1330℃ and 1300℃. The results of SEM show that reduction of sintering temperature decreases grain size effectively, and the pores in grain are eliminated. The results also show that the grain is more uniform and the grain boundary is clearer. The results of electromagnetic performance indicate that sintering temperature has insignificant effect on initial permeability, but magnetic flux density increases and power loss decreases significantly at 100kHz/200mT and 100℃ while sintering temperature drops. The power loss is about 255kW/m3, for sample sintered at 1300℃.By the loss separation, improvement of total power loss is mainly a result of drop in the eddy current loss.%使用同一配方制备得到的锰锌铁氧体坯件分别在1360℃、1330℃、1300℃下采用平衡气氛法烧结，制备得到致密的锰锌铁氧体磁环。SEM结果表明，降低烧结温度有效地减小了晶粒尺寸，消除了晶粒内部气孔，改善了晶粒均匀程度，使晶界更为清晰。电磁性能测试表明，在三种温度烧结得到的锰锌铁氧体材料的起始磁导率μi没有显著差异；饱和磁感应强度Bs随烧结温度降低有小幅上升；总功率损耗随烧结温度的降低而下降；并且在1300℃烧结的铁氧体材料的功率损耗（100kHz/200mT，100℃）很低，约为255kW/m3。通过损耗分离证实，总功率损耗的改善主要是涡流损耗大幅降低所致。