摘要
在建立电场活化烧结(field activated sintering,FAS)过程模型基础上,对FAS工艺制备MoSi_2-SiC复合材料的温度场进行了有限元模拟.结果表明,在FAS过程中,模具-试样系统中的温度场特性是电场Joule热、体系化学反应热与模具传热效应的综合结果.在烧结过程中,由于Joule热与化学热的叠加作用,试样中心温度最高,并沿径向与轴向形成温度梯度,从而在晶粒尺寸与致密化程度方面影响合成材料的组织均匀性.此模拟结果为温度梯度的合理控制提供了理论依据,有助于获得组织均匀、晶粒细小且致密性高的复合材料.
Finite element modeling of temperature distribution in field activated sintered （FAS） MoSi2-SiC composite was made on the basis of modeling for FAS process. The results show that FAS temperature field is determined by a combined effect of Joule heat of electric field, heat released by chemical reaction, and transferring heat in die-specimen system. Due to overlap of heats produced by Joule effect and chemical reactions, the center temperature is the highest in the sample, a radius and axial temperature gradients are formed, which significantly affect the uniformity of microstructure in the sizes and densifications of grains. The simulation results provide a theoretical support on temperature gradient controlling, which help to prepare dense and fine grained bulk materials.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2008年第10期1253-1259,共7页
Acta Metallurgica Sinica
基金
国家自然科学基金重点项目50531030
国家自然科学基金项目50574042资助~~
