氟化铝对镁铝尖晶石晶相结构及性能影响的研究

Influence of aluminium fluoride on crystalline structure and properties of magnesium aluminate spinel

用铝型材厂阳极氧化废渣和碱式碳酸镁((MgCO3)4.Mg(OH)2.5H2O)为主要原料固相烧结合成镁铝尖晶石(MgAl2O4),探讨氟化铝(AlF3)矿化剂对合成的MgAl2O4晶相结构、晶胞参数及微观形貌的影响.用X射线衍射(XRD),扫描电镜(SEM)及相关分析软件等表征得到MgAl2O4.结果表明,添加AlF3的各样品都形成2种晶相:镁铝尖晶石固溶体(Mg0.68Al0.32)(Al0.84Mg0.16)2O4和镁橄榄石固溶体Mg1.81Fe0.19(SiO4).确定2%(质量分数)为最佳添加量,此时试样中MgAl2O4固溶体含量最高为95%,体积密度最高为3.44 g.cm-3,显气孔率最小为1.89%,抗弯强度达到151.9 MPa.

Aluminate spinel（MgAl2O4） has been prepared following solid state reaction by using waste slag from aluminum factory and （MgCO3 ）4·Mg（ OH）2 · 5H2O as main starting materials. The influence of AlF3 mineralizer on the crystalline structure, unit cell parameters, microstruetures and properties were discussed. X- ray diffraction （XRD） and scanning electron microscopy （SEM） were used to characterize the crystalline phases and microstructures. Philips plus software and Rietveld quantification techniques were used to characterize and calculate the target phase. The results show that two kinds of crystalline phases are formed in each sample, corresponding to （Mg0.68Al0.32）（Al0.84Mg0.16）2O4 and Mg1.81Fe0.19（SiO4）. The best adding amount for AIF3 is determined to be 2%, the corresponding MgAl2O4 content is up to 95%, bulk density is 3.44 g · cm^-3, apparent porosity is 1.89% and bending strength is 151.9 MPa.