| For the sake of researching the effect of the contents of Ni, Mn and the processof Ni/Mn/BaTiO3 PTC composites were manufactured. To obtain a low resistivity ofthe PTC composites Ni and Mn powders were added into BaTiO3 PTC ceramics. Theaim of adding Ni is to reduce the resistivity of the PTC composites. The aim of addingMn is not only improving the PTC jump of the PTC composites but also keeping Nifrom oxygenated.The contents of Ni, Mn and the process of Ni/Mn/BaTiO3 PTC composites caninfluence the electric properties and microstructures. They were analyzed in thisarticle by means of XRD, SEM, TG-DSC and analyzing the results and data of theexperiments. The process including the sintering process and the annealing processwere discussed in this article. In the part of sintering process the sintering temperatureand the sintering atmosphere were discussed. The experiments showed that the bestsintering temperature is around 1260℃~1270℃. The technical highlights of partialreductive atmosphere process and the effect of this process were also discussed inparticular. The experiments showed that partial reductive atmosphere process is betterthan the reductive atmosphere process but the content of graphite must be controlledcarefully. In the part of annealing process the annealing temperature and the annealingtime were discussed. Through the experiments we can conclude that the annealingtemperature should be around 950℃ and the annealing time should be no longer than60 min.The discussing of prescription includes the contents of Ni and Mn, the electricproperties and microstructures of Ni/Mn/BaTiO3 PTC composites. When the contentsof Ni is around 5%~10% the resistivity of PTC composites can be reduced effectively.The PTC jump can also be keeping at a perfect level.We discussed the function of Ni and Mn in the PTC composites in this work. Byanalyzing the results and data of the experiments the rules of the experiments weresummarized and a physical model of Ni/Mn/BaTiO3 PTC composites was established.
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