烧结条件对强磁场中成型氮化硅织构化的影响

Effect of Sintering Conditions on Texture Formation of Si_3N_4 Ceramic Shaped up in a Strong Magnetic Field

采用凝胶注模成型方法在6T纵向强磁场中制备氮化硅陶瓷素坯,经磁场外无压烧结制备出a轴或b轴取向的织构化氮化硅陶瓷,研究了烧结温度和保温时间对氮化硅陶瓷织构化形成的影响规律。结果表明:在本文的烧结条件下α-Si3N4全部转变为β-Si3N4。烧结温度的提高促进了氮化硅陶瓷织构化的提高,从1700℃的0.40增加到1800℃的0.76。烧结温度为1750℃时,烧结时间的延长对织构度的发展几乎没有影响。

Si3N4ceramics with preferential texture along a or b axis were shaped up by gel-casting in a magnetic field of 6T and then pressureless sintered. Effect of the sintering temperature and time on the texture formation of the Si3N4 ceramics was investigated. It was found that the phase transformation of αto β was completed for the Si3N4 ceramics prepared by the present process. With the increasing sintering temperature the texture formation of Si3N4 ceramics may be enhanced, i.e. of which the degree of texture increased from 0.40 at 1700℃ to 0.76 at 1800℃. The extension of sintering time at 1750℃ had few effect on texture development of Si3N4 ceramics.