粉浆浇注制备铁基梯度复合材料的研究

利用粉浆浇注-熔渗法制备Fe-WC-Cu复合材料。研究(NaPO3)6、粉末装载量,Fe和WC粒度以及石膏模膏水比对梯度形成的影响。利用浇注方向上等距离位置硬度的变化,定性地研究WC的分布。结果表明:(NaPO3)6的引入能提高浆料稳定性,不利于WC梯度形成;粉浆浇注过程颗粒偏析是由重力场的沉降作用和细颗粒引起的Clogging效应共同决定;减小石膏模具膏水比、提高粉末装载量、以及合理的粒度组成能有效抑制Clogging效应,制备WC体积分数在浇注方向呈递增的Fe基复合材料。简单研究了粉浆浇注梯度形成机理。

Study on Preparing Fe-base Gradient Composites by Slip Casting

Fe-WC-Cu composites were produced by slip casting and copper infiltration method.The effects of(NaPO3)6,powder loading amount,particle size of Fe and WC powder,and ratio of plaster to water of mould on gradient were studied.Variety trend of hardness in equidistance testing position at casting direction was studied to qualitatively discuss the distribution of WC.The results show that stability of slurry can be improved and gradient of WC can be prevented with additive of(NaPO3)6;particle segregation in slip casting is induced by gravity force and clogging effect of fine particles which can be effectively controlled by decreasing ratio of plaster to water,increasing powder loading,and appropriate particle size distribution.Fe based composites with incremental WC volume percentage at casting direction can be produced.Mechanism of gradient forming is also briefly studied.