作者:KOICHI SHIMIZU;JYOUKI YOSHITOMI;MASAAKI MISHIMA HIDEYUKI ANDO;
作者单位:
刊名:Taikabutsu Overseas
ISSN:0285-0028
出版年:2001-01-05
卷:21
期:2
起页:105
止页:110
分类号:TQ175
语种:英文
关键词:
内容简介Historically, Ca(OH)_2 is the main mineralizer that has been used in silica bricks. It was found that Ca(OH)_2 is an excellent mineralizer that has the necessary characteristics of promoting the formation of tridymite, enhancing the sintering behavior, and increasing the strength.MnO_2 was found to be a mineralizer with nearly the same characteristics as mentioned for Ca(OH)_2. In addition, MnO_2 has the benefit of providing sufficient pot life for the plastic body, which allows flexibility in the manufacturing process because there is no reaction with binders, such as pulp drainage or phenol resin. It appears that MnO_2 results in better volume stability at lower temperature than the conventional products, because it is more effective in forming tridymite than Ca(OH)_2.On the other hand, the samples to which alkali metals (Na, Li compounds) were added, converted almost entirely to cristobalite (i.e., neatly a single phase material) after firing at 1450 deg C X 30 hrs., but they are inferior in their densification effect. Volume stability is a drawback for samples that are composed mainly of cristobalite, but there is a good possibility that they have a higher thermal conductivity compared with tridymite-rich samples. The mineralizers for silica bricks must be studied that promote both the development of cristobalite and densification of the structure, that may provide higher thermal conductivity than Ca(OH)_2 (i.e., the conventional mineralizer) for silica brick.
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