收录:
摘要:
Ca3Co4O9 ceramics were prepared by sol-gel method and spark plasma sintering (SPS) process. The influence of SPS process on the phase, microstructure and electrical properties of the ceramics were investigated by XRD, SEM, etc. The results show that plate-like powders and SPS process especially, increasing of sintering temperature are beneficial to form Ca3Co4O9 texture. It is suggested that the rearrangement of the plate like powder took place under the magnetic field derived from pulsed current in SPS process, resulting in the powder orientation. In our experimental range, the orientation degree of Ca3Co4O9 bulk increased from 0.75 to 0.87, and electrical resistivity decreased from 6.24 x 10(-5) Omega.m to 5.59 x 10(-5) Omega.m, when the SPS temperature was from 750 degrees C to 900 degrees C. In addition, Ca3Co4O9 bulk showed classical electrical character of semiconductor, the electrical conductivity of samples increased with increasing temperature. The maximum electrical conductivity was obtained at 700 degrees C for p-type Ca3Co4O9 compounds when the SPS temperature was 850 degrees C.
关键词:
通讯作者信息:
电子邮件地址: