硅微粉对ρ-Al_2O_3结合莫来石浇注料的影响
|
摘要
以各种粒度烧结莫来石做骨料,以棕刚玉细粉和氧化铝微粉为基质,以ρ-Al2O3微粉为结合剂,制备了莫来石浇注料,研究了不同硅微粉加入量对浇注料性能的影响,并借助XRD、SEM等对其物相和显微结构进行检测。结果表明:随着硅微粉量的增大,浇注料强度呈现先升高后降低的变化规律,高温抗折强度在硅微粉加入量为6%时达到极值。主要原因在于:硅微粉加入适量能形成液相促进烧结,并在基质中形成较多莫来石,提高了高温强度;硅微粉加入过多时,产生过烧结,在试样中产生大量液相并形成较多裂纹,又使得高温抗折强度降低。
Mullite based castables were prepared by using sintered mullite with various particle size as aggregates,brown corundum fines and alumina micropowder as matrix,and ρ-Al2O3 as a binder. The effects of different silica powder additions on room temperature physical properties and hot modulus of rupture( HOMR) were investigated. X-ray diffraction( XRD) and scanning electron microscopy( SEM)were adopted to characterize the phase composition and microstructure. The results show that with silica powder increasing,the strength of the castables first increases and then decreases,and the HOMR reaches a maximum at 6% silica powder addition. The main reason is that an appropriate silica powder addition could yield liquid phase contributing to sintering and produce more mullite in the matrix enhancing the HMOR. Excess silica powder will make the material over-sintered and considerable liquid phase and more cracks formed,which in turn decreases the hot modulus of rupture.
Mullite based castables were prepared by using sintered mullite with various particle size as aggregates,brown corundum fines and alumina micropowder as matrix,and ρ-Al2O3 as a binder. The effects of different silica powder additions on room temperature physical properties and hot modulus of rupture( HOMR) were investigated. X-ray diffraction( XRD) and scanning electron microscopy( SEM)were adopted to characterize the phase composition and microstructure. The results show that with silica powder increasing,the strength of the castables first increases and then decreases,and the HOMR reaches a maximum at 6% silica powder addition. The main reason is that an appropriate silica powder addition could yield liquid phase contributing to sintering and produce more mullite in the matrix enhancing the HMOR. Excess silica powder will make the material over-sintered and considerable liquid phase and more cracks formed,which in turn decreases the hot modulus of rupture.
引文
[1]杜春生,葛志平,杨正方,等.溶胶-凝胶法合成高纯锆英石粉[J].硅酸盐学报,1999,27(3):346-350.
[2]李跃龙,黎建明,苏小平,等.红外窗口和整流罩材料研究现状与发展趋势[J].人工晶体学报,2007,36(4):877-885.
[3]欧阳德刚,胡清明,向在良,等.气化室脱硫喷枪耐火浇注料的研究与应用[J].钢铁研究,2006,34(2):34-37.
[4]李洪波,赵继增,陈奇.ρ-Al2O3加入量对莫来石-刚玉浇注料性能的影响[J].耐火材料,2008,42(1):11-14.
[5]贺智勇,杨粉荣,张岩等.Si O2微粉加入量对ρ-Al2O3微粉结合刚玉浇注料的影响[J].耐火材料,2009,43(2):6-9.
[2]李跃龙,黎建明,苏小平,等.红外窗口和整流罩材料研究现状与发展趋势[J].人工晶体学报,2007,36(4):877-885.
[3]欧阳德刚,胡清明,向在良,等.气化室脱硫喷枪耐火浇注料的研究与应用[J].钢铁研究,2006,34(2):34-37.
[4]李洪波,赵继增,陈奇.ρ-Al2O3加入量对莫来石-刚玉浇注料性能的影响[J].耐火材料,2008,42(1):11-14.
[5]贺智勇,杨粉荣,张岩等.Si O2微粉加入量对ρ-Al2O3微粉结合刚玉浇注料的影响[J].耐火材料,2009,43(2):6-9.