Fe基多孔材料瞬时液相烧结过程研究

Study on forming process of Fe-based porous materials by transient liquid phase sintering with Ni-P eutectic powders

采用定量DSC差热分析、扫描电镜分析、背散射元素分析以及XRD物相分析等方法对添加Ni-P共晶合金的Fe粉瞬时液相烧结过程进行了研究。研究发现,粉末颗粒粒度、烧结时间等参数对烧结过程有重要的影响。粉末粒度较小时,烧结升温过程中元素间的固相扩散比较明显,但粉末粒度对形成液相的总量影响较小。液相烧结时,固相Fe元素向液相中的扩散速率快于液相Ni元素向固相Fe颗粒内的扩散速率。P元素可在固相Fe粉内快速扩散均匀,但随着烧结时间的增加,P元素在Fe颗粒中产生偏聚,形成(FeNi)3P化合物。随着保温时间的增加,液相组分熔点升高,液相量逐渐减少,最后实现多孔材料的瞬时液相烧结。

Transient liquid sintering process of Fe powders with Ni-P eutectic alloys were studied using DSC,SEM,BSE and XRD.The results show that parameters of powder size and sintering time significantly affect sintering process.With a decrease of powder size,the solid-state diffusion increase,while with a small effect of powder size on total liquid amount.When liquid sintering occur,diffusion of Fe into liquid phase is faster than that of liquid Ni into Fe powders.P diffuse into Fe within a short time,it is followed by segregation of P in Fe powder with increasing sintering time and formation of（FeNi）3P in Fe powders.With increasing holding time,the melting point of liquid phase component rise,and the content of liquid gradually decrease.Transient liquid phase sintering of porous material is achieved.