作者：AKIHIRO TSUCHINARI;HIROM1 HAMANAKA;TOYOYASU OBANA;

作者单位：Itochu Ceratech Corp. 11-4, Shiokusa-cho, Seto-shi, Aichi 489-0895;Itochu Ceratech Corp. 11-4, Shiokusa-cho, Seto-shi, Aichi 489-0895;Itochu Ceratech Corp. 11-4, Shiokusa-cho, Seto-shi, Aichi 489-0895

刊名：Journal of the Technical Association of Refractories

ISSN：0285-0028

出版年：2011-01-05

卷：31

期：2

起页：83

止页：89

分类号：TQ175

语种：英文

关键词：CaO brick;MgO;ZrO_2;Spalling resistance;Griffith crack;

内容简介

The influences of MgO and ZrO_2 additions on the thermal spalling resistance of CaO brick were investigated. The thermal spalling resistance was significantly improved by optimizing the content of both MgO and ZrO_2. The reason for the improvement is that a large number of cracks are generated in CaO brick by the additions. Considering the existence of relatively large Griffith cracks, the thermal spalling resistance can be understood with the relational expressions of apparent porosity and flexural bending strength based on D. P. H. Hasselman's "unified theory of thermal shock fracture initiation and crack propagation in brittle ceramics." MgO contributes to the prevention of the densification of CaO brick at high temperatures. Stable reaction products in CaO bricks containing both MgO and ZrO_2 are CaO_(0.15)Zr_(0.85)O_(1.85) and CaZrO_3. It is clarified that the existence of MgO has a great effect on the formation of CaO_(0.15)Zr_(0.85)O_(1.85), especially, during the initial temperature increase on sintering and in the initial period of reaction.