High temperature refractory of MgCr2O4 matrix and unstabilized ZrO2 particles

摘要

A high chromia refractory composite has been developed with improved thermal shock resistance and containing about 5-30 wt. % of unstabilized ZrO2 having a temperature-dependent phase change resulting in large expansion mismatch between the ZrO2 and the chromia matrix which causes microcracks to form during cooling in the high chromia matrix. The particle size preferably is primarily between about 0.6-5 microns and particularly below about 3 microns with an average size in the order of 1.2-1.8 microns.