摘要 |
Certain derivatives of the lanthanide elements greatly enhance the strength of heated alumina refractories in the 500 to 1000 degree Fahrenheit temperature range. Cerium oxide, for example, when added in 1 percent to 5 percent by weight to commercial calcium aluminate cement with tabular alumina aggregate, plus 10 to 30 percent water, and fired at 500 to 1000 degrees Fahrenheit, forms a ceramic bond and becomes as strong as untreated calcium aluminate refractory concrete fired at 2000 degrees Fahrenheit. The cerium modified refractory concrete is 1000 psi to 1500 psi stronger than unmodified refractory concrete at 500 to 1000 degrees Fahrenheit.
|