Patent ID: 8399372

Claim:
A refractory material comprising: (i) at least 20 wt. % of a first grain mode based upon the total weight of said refractory material, said first grain mode comprising stabilized zirconia having a D50 grain size in the range of from 5 to 2000 μm, said stabilized zirconia including a matrix oxide stabilizer; (ii) at least 1 wt. % of a second grain mode having a D50 grain size in the range of from 0.01 μm up to not greater than one-fourth the D50 grain size of said first grain mode zirconia, based upon the total weight of said refractory material, wherein said second grain mode comprises a fully stabilized zirconia, said second grain fully stabilized zirconia is stabilized by a second grain mode zirconia stabilizer; and (iii) said refractory material comprising at least 1 wt. % of a preservative component; wherein after sintering said material has porosity at 20° C. of from 5 to 45 vol %.