摘要
以低品位菱镁矿与天然硅石为原料,利用固相反应烧结制备镁橄榄石。通过添加氧化铬,分析氧化铬对镁橄榄石材料相组成、晶胞参数、微观结构及常温性能的影响。用X射线衍射、扫描电镜及用X'pert plus软件对烧后镁橄榄石试样的晶相组成、显微结构和晶相晶胞参数进行表征和计算。结果表明:利用活性氧化镁粉与硅石经1500℃高温煅烧可以制备出镁橄榄石材料。氧化铬加入导致镁橄榄石相的晶胞参数和晶胞体积的增大。Cr3+的电场作用,减弱镁橄榄石中Mg-O的键力,导致镁橄榄石中顽火辉石相的增多。适量氧化铬促进镁橄榄石烧结,提高镁橄榄石的致密度和常温强度,确定氧化铬最佳加入量为(0.8～1.2)%。
Forsterite was prepared by solid reaction of raw materials of low-grade magnesite and natural silica with different content of zirconia as additive. The effect of Cr203 on composition, microstructure and lattice parameters of crystalline phases was studied. Crystalline phases and microstructure were determined by XRD, SEM and X＇Pert plus software. Bulk density, porosity and water absorption of the forsterite were measured, and its crush strength was tested at room temperature. Results show that forsterite can be synthesized from low-grade magnesite and natural silica by addition of Cr203. The lattice parameters and unit cell volume of forsterite are decreased by the addition of Cr203 in the reactants. The band of Mg-O is weakened by the interaction of Cr3＋ with higher intensity of ionic field, which results in the formation of enstatite in the structure of forsterite. Through adding appropriate Cr2 O3 , the density and crush strength of the forsterite are improved by the increase of its compactness. The appropriate addition of Cr203 in the forsterite is determined to be 0. 8-1. 2% in mass fraction.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2013年第1期21-25,共5页
Transactions of Materials and Heat Treatment
基金
辽宁省镁资源保护办公室资助项目(2011)
