【摘要】 以铁尾矿合成的SiC粉为原料,Y2O3和Al2O3为烧结助剂,常压烧结制备SiC-Y3Al5O12(YAG)复相陶瓷。通过X射线衍射及扫描电镜等测定材料的相组成和显微结构,并分析烧结物的致密化过程,研究其结构和力学性能。结果表明:制备材料适宜的烧结温度为1800~1850℃。烧成产物主要物相为SiC,其余为YAG和少量FexSiy。随烧结温度的升高,Y2O3和Al2O3生成的YAG相逐渐增加且稳定存在。细小的YAG颗粒弥散在基体周围,并逐渐增多聚集把短柱状SiC晶粒粘结在一起起到促进烧结的作用。随烧结温度的升高,材料的显气孔率降低,而体积密度、硬度和抗压强度均增加。更多还原

【Abstract】 SiC-Y3Al5O12(YAG)composite ceramics were prepared by pressureless sintering using SiC powder synthesized from iron ore tailings added with Y2O3 and Al2O3 powders.The phase composition and microstructure were determined by X-ray diffraction and scanning electron microscopy.The densification process of sinter is analyzed,and structure and mechanical properties were studied.The results show that the main phase of sinter was SiC,others are YAG and a little FexSiy.The YAG phase formed from Y2O3 and Al2O3 increases and becomes stable with increasing sintering temperature.Fine YAG grains,which disperse around the SiC,grow gradually,bonded shot columnar SiC together playing a role of sintering accelerator.With the increase of sintering temperature,the apparent porosity of sample decreases,while bulk density,hardness and compressive strength increased.更多还原