配料组成与合成温度对蛇纹石合成堇青石的影响

摘要

Cordierite was prepared at high temperatures using serpentine powder from Donghai Lianyunga-ng as the main starting material,adding α-Al2 O3 and quartz powder.Five formulations were adopted:stoi-chiometric,SiO2 addition 5% or 10% higher than the stoichiometric,and Al2 O3 addition 5% or 10% higher than the stoichiometric.The batched materials were ball milled,granulated,dried,cold isostatic pressed and fired at 1 050,1 100,1 150,1 200,and 1 250 ℃for 2 h,respectively.The apparent porosity,bulk density and cold modulus of rupture of the prepared specimens were tested,and specimens were analyzed by XRD and SEM.The results show that the synthesized cordierite has a complete hexagonal columnar mor-phology;increasing quartz powder addition reduces the synthesis temperature,obtaining denser cordier-ite;increasing α-Al2 O3 addition leads to porous cordierite with a loose structure.%以连云港市东海蛇纹石粉为主要原料，辅以α-Al2 O3和石英粉高温合成堇青石，分别配成符合理论组成的配方，SiO2质量分数比理论组成分别多5和10百分点的配方，以及Al2 O3质量分数比理论组成分别多5和10百分点的配方，经球磨、造粒、烘干、冷等静压成型后，分别在1050、1100、1150、1200和1250℃保温2 h，然后检测试样的显气孔率、体积密度和常温抗折强度，并进行XRD和SEM分析。结果表明：合成的堇青石呈较完整的六方柱状形貌；增大石英粉的添加量能降低材料的合成温度，制得致密度较高的堇青石材料；增大α-Al2 O3添加量，合成的堇青石气孔较多，结构疏松。