选取膨润土作为陶瓷基体,以鳞片石墨、预处理石墨及炭黑作为导电原料,碳化硅作为增强原料,经球磨混合、50MPa模压成型和1000℃热处理3h后制备出炭/陶复合电热材料。采用XRD和SEM对其物相组成和微观形貌进行表征,并对其通电发热性能、力学性能和抗氧化性能进行了测试和分析。所制备的炭/陶复合材料具有优异的电热性能,在交流低电压(10V)下即可迅速升温,并在较高温度下保持相对稳定,研制的样品中最高发热温度可达643℃。通过调整碳化硅含量,复合材料抗弯强度可达14.3MPa。通过将炭材料和陶瓷材料复合,可有效改善炭材料的抗氧化性,使其明显氧化失重温度升高200℃左右。
The electric heating carbon/ceramic composites were prepared by blending,ball milling,50MPa die forming and 1000℃ non-oxidizing sintering for 3h of raw materials,which include ceramic matrix of bentonite and conductive components of flake graphite,pretreated graphite,black carbon and SiC as reinforced part.The phase and micromorphology of the carbon/ceramic composites were characterized and analyzed by XRD and SEM.The research of electrothermal property,mechanical property and antioxidation were carried on.Electric heating carbon/ceramic composites prepared possess superior electric heating property,which showed a rapid increase and then a relative stability in temperature only at a low voltage of 10V.The best performing one could rise to 643℃.By modifying content of SiC,flexural strength of the composite could reach to 14.3MPa.By combining carbon materials and ceramic materials,oxidation-resistance of carbon materials can be improved effectively for rasing the weight losing temperature of 200℃.