摘要
在球墨铸铁的高温石墨化过程中采用脉冲电流为辅助手段,研究了脉冲电流对退火处理球墨铸铁力学性能以及渗碳体的石墨化、铁素体转变的影响.经脉冲电流处理后,球墨铸铁的硬度、抗拉强度降低,延伸率增加.SEM分析表明,脉冲电流加速了球墨铸铁的高温石墨化过程,促进了铁素体的转变.脉冲电流处理后石墨形核率的增加是加速渗碳体分解和铁素体转变的主要原因.
The effects of pulse current on the mechanical properties of spherical graphite iron, the graphitization of cementite and the transformation of ferrite were studied during the high-temperature graphitization of spherical graphite iron with pulse electric current as an assistant way. The results show that the tensile strength and the hardness of the specimen decrease, while the elongation increase. SEM micrographs of the specimen show that electropulsing promotes greatly the high-temperature graphitization of spherical graphite iron and the transformation of ferrite. The acceleration of cementite decomposition and the transformation of ferrite result from the increase of graphite nucleation rate by electropulsing.
出处
《北京科技大学学报》
EI
CAS
CSCD
北大核心
2008年第8期854-857,902,共5页
Journal of University of Science and Technology Beijing
关键词
球墨铸铁
脉冲电流
渗碳体
铁素体
石墨化
spherical graphite iron
pulse current
cementite
ferrite
graphitization
