稻壳灰制备Si_3N_4/SiC复合粉体的研究

Preparation of Si_3N_4/SiC Composite Powders Using Rice Husk Ash

本文主要研究不同的SiO2∶C比例对所制备Si3N4/SiC复合粉体组成的影响。采用生物质能电厂所产生的工业废弃物稻壳灰和炭黑为原料,以稻壳灰中的SiO2为标准与炭黑配成不同比例的粉料,在氮气气氛下经1550℃保温3 h热处理。采用X射线衍射(XRD)和扫描电子显微镜(SEM)分析烧后试样的物相组成和显微结构。结果表明:当SiO2∶C为5∶6时得到的产物为Si3N4/SiC复合粉体;当SiO2∶C为5∶2和5∶3时,得到产物的组成为SiC、O'-Sialon和β-Si3N4。

The effects of SiO2/ C ratio on the synthesis of Si3N4/ SiC powders were investigated.A large number of rice husk ash（RHA） is produced in the biomass cogeneration plant using rice husk as fuel.For utilization of this kind of industrial waste,Si3N4/ SiC powders were synthesized with RHA and carbon black mixed in weight ratios sintered at the temperature 1550 ℃ in nitrogen.The phase composition and microstructure of samples were characterized by X-ray diffraction（XRD） and scanning electron microscopy（SEM）.The results show that the Si3N4/ SiC were synthesized when SiO2∶ C ratio is 5∶ 6,and when SiO2∶ C ratio is 5∶ 2 and 5∶ 3,the product were composed of SiC,O＇-Sialon and β-Si3N4.