(上海大學(xué) 材料科學(xué)與工程學(xué)院,
上海市現(xiàn)代冶金與材料制備重點(diǎn)實(shí)驗(yàn)室, 上海 200072)
摘 要: 在共沉淀制備非鐵磁性錳鋅鐵氧體前驅(qū)體納米顆粒的過程中, 分別施加零磁場、 弱磁場(0.1~0.7 T)和強(qiáng)磁場(10 T),探討磁場對(duì)非鐵磁性錳鋅鐵氧體前驅(qū)體納米顆粒形貌的影響規(guī)律。 結(jié)果表明, 當(dāng)磁感應(yīng)強(qiáng)度超過某一臨界值時(shí), 非鐵磁性納米顆粒由球形顆粒向鏈狀顆粒, 然后向棒狀或者纖維狀顆粒轉(zhuǎn)變。在10 T的強(qiáng)磁場下, 納米顆粒長成長徑比很大的纖維狀, 能譜分析結(jié)果表明, 纖維狀顆粒主要為復(fù)合鐵氧體, 而非單一的沉淀產(chǎn)物。隨著反應(yīng)溫度增加、 溶液滴加時(shí)間延長將使纖維直徑降低。
關(guān)鍵字: 強(qiáng)磁場; 非鐵磁性納米顆粒; 形貌; 共沉淀
MnZn ferrite nano-precursor particles
( Shanghai Enhanced Laboratory of Modern Metallurgy and Material Processing,
School of Materials Science and Engineering, Shanghai University 200072, China)
Abstract: The preparations of non-magnetism nano-precursor particles of MnZn ferrite were carried out in the zero magnetic field, weak magnetic field and high static magnetic field, respectively, and the effect of the magnetic field on the shape of the nano-particles was discussed. The results show that, there is a critical magnetic flux density (MFD), above which the shape of the nano-particles changes from spheric to chainlike, then to fibre-like. In the magnetic field with MFD equaling to 10 T, the nano-particles have the shape of fibre with high ratio between length and diameter; and the composition of the fibre is mainly ferrite compound, not single oxide, which was judged from analysis results by energy spectrum. The diameter of the fibre decreases when the reaction temperature is increased or the adding time of reagent solution is prolonged.
Key words: high static magnetic field; non-magnetism nano-particles; shape; co-precipitation


