燃烧法合成高纯度负热膨胀材料ZrW_2O_8粉体  

HIGH PURE NEGATIVE THERMAL EXPANSION MATERIAL ZrW_2O_8 POWDERS SYNTHESIZED BY COMBUSTION METHOD

作　　者：严学华[1] 杨新波[1] 程晓农[1] 付廷波[1] 邱杰[1] 刘红飞[1] 

机构地区：[1]江苏大学材料科学与工程学院,江苏镇江212013

出　　处：《硅酸盐学报》2006年第9期1066-1069,1074,共5页Journal of The Chinese Ceramic Society

基　　金：国家自然基金(50372027;50442023)资助项目;江苏省研究生创新基金资助项目

摘　　要：采用燃烧法在较低温度下成功合成了各向同性的负热膨胀材料ZrW2O8粉体。用X射线衍射、扫描电镜、红外光谱综合分析和研究了反应过程中炉温、硼酸和尿素含量、W6+与Zr4+的摩尔比对合成ZrW2O8纯度的影响。结果表明:燃烧法可以合成高纯度、粒径为0.5μm的ZrW2O8粉体。燃烧法合成高纯ZrW2O8的最佳条件是:炉温为500℃,硼酸的摩尔分数为10%,(NH2)2CO与(NH4)5H5[H2(WO4)6]·H2O+ZrOCl2·8H2O的质量比为2:1,(NH4)5H5[H2(WO4)6]·H2O与ZrOCl2·8H2O的摩尔比为1:3.2。所合成的ZrW2O8在50～700℃之间的线膨胀系数α=-5.08×10-6/℃,其线膨胀系数与温度的关系符合方程dL/L0=-1.4×10-2-4.5×10-4T(50℃≤T≤700℃)。Isotropic ZrW2O8 powders material with negative thermal expansion were successfully synthesized via combustion method at low temperature. The effects of the furnace temperature, the H3BO3 and （NH2）2CO content, and the molar ratio of W^6＋ and Zr^4＋ on the purity of the synthesized ZrW2O8 powders were investigated by X-ray diffraction, scanning electron microscopy and infrared spectrum. The results show that high purity ZrW2O8 powders with a mean particle size of 0.5μm, can be obtained by the method under the following conditions： a furnace temperature of 500℃; a H3BO3 molar fraction of 10%; a 2：1 mass ratio of （NH2）2CO and （NH4）sHs[H2（WOn）6]·H2O added to ZrOCl2·8H2O; and a 1：3.2 molar ratio of （NHn）5H5[H2（WOn）6]·H2O and ZrOCl2·8H2O. The linear thermal expansion coefficient of prepared ZrW2O8 material is -5.08×10^-6/℃ in the temperature range from 50℃ to 700℃. The equation for the relationship of thermal expansion to the temperature of the material is dL/L0=-1.4×10^-2-4.5×10^-4T .

关 键 词：钨酸锆 负热膨胀材料 燃烧合成 热膨胀系数 

分 类 号：TQ174[化学工程—陶瓷工业]