Abstract
Refractoriness-under-load measurements were carried out on two kinds of burnt magnesia bricks under the load ranging from 1 to 30kg/cm2 and the effect of load on the temperature of deformation and failure was investigated. It was estimated that the mechanism of deformation and failure under loads below about 10kg/cm2 is different from that above. The mechanism will be classified into two types, ie, lower-temperature-higher load type and higher temperaturelower load type. It was found that the liquid formation will play an important role in the process of deformation and failure in higher temperaturelower load type, and that the failure under the standard load 2kg/cm2 will take place when the liquid amounts to about 15%.
The deformation and failure under loads was found to have such relation with the microstructure of bricks that it proceeds with the change in matrix part in brick. Some points to be improved in R-u-L test were proposed.
