粉末冶金原位合成VC/Fe复合材料的动力学过程研究

Study on dynamics process of VC/Fe composite materials fabricated in situ by powder metallurgy

应用不同烧结温度制备VC颗粒增强铁基复合材料,用扫描电镜(SEM)观察各烧结温度下的微观结构,应用该组分做差热分析(DTA)、高温X射线衍射分析(XRD)对Fe-V-C体系原位合成VC的动力学过程进行研究,该动力学研究将为VC/Fe复合材料制备提供了理论依据。结果表明,在700℃时左右σ相(Fe V)在石墨的作用下发生分解,变成固溶了大量钒的α-Fe,随着温度的升高,V与C发生反应生成VC;温度越高,VC发生反应越激烈,并释放出大量的热量;1 100℃真空烧结后的组织为珠光体基体上分布着大小均匀呈球形的VC颗粒。

VC particles reinforced iron matrix composites were fabricated at different sintering temperature.U-sing scanning electron microscopy （SEM）,the microstructures were observed.Dynamics process of the Fe-V-C system were analyzed by DTA and high temperature XRD,the dynamics study will provide a theoretical basis for VC/Fe composite material preparation,the results showed thatσ-（FeV）in the Fe-V-C system decomposed at 700 ℃,and became into α-Fe lots of vanadium atoms soluted in,with the temperature increasing,V and C react to VC;the higher the temperature,the VC reaction more intense,and release a lot of heat;after sintering in vacuum at 1 100 ℃,the microstructure of the composite was VC particles uniformly distributed spherical on pearlitic matrix.