ULTRA-LOW THERMAL MASS REFRACTORY ARTICLE
An ultra-low thermal mass refractory article includes fibers impregnated with a colloidal inorganic oxide. The refractory article has at least one of the following properties: (i) a density of 500 kg/m 3 to 1500 kg/m 3 ; (ii) a thermal conductivity of 1.0 Wm/K or less at 700° C.; and/or (iii) a linear thermal shrinkage at 1400° C. of less than 2.5%.
1 . A refractory article comprising inorganic fibers and having at least one of the following properties:
(i) a density of 500 kg/m 3 to 1500 kg/m 3 ;
(ii) a thermal conductivity of 1.0 Wm/K or less at 700° C.; and/or
(iii) a linear thermal shrinkage at 1400° C. of less than 2.5%.
2 . The refractory article of claim 1 , wherein the inorganic fibers are selected from polycrystalline wool, aluminosilicate fibers, alumino zirconia silicate fibers, and/or alkaline earth silicate fibers.
3 . The refractory article of claim 1 , comprising a thermal conductivity of 0.5 Wm/K or less at 700° C.
4 . The refractory article of claim 1 , comprising a thermal conductivity of 0.2 Wm/K or less at 700° C.
5 . The refractory article of claim 1 , comprising a linear thermal shrinkage at 1400° C. of less than 1.5%.
6 . The refractory article of claim 1 , comprising a linear thermal shrinkage at 1400° C. of less than 1.0%.
7 . The refractory article of claim 1 , comprising a density of 800 kg/m 3 to 1000 kg/m 3 .
8 . The refractory article of claim 1 , wherein the refractory article has the following properties:
(i) a density of 800 kg/m 3 to 1000 kg/m 3 ;
(ii) a thermal conductivity of 0.2 Wm/K or less at 700° C.; and
(iii) a linear thermal shrinkage at 1400° C. of less than 1.0%.
9 . A method of forming a refractory article, the method comprising:
impregnating inorganic fibers with at least one colloidal inorganic oxide or phosphoric acid,
placing the impregnated fibers in a mold;
pressing the impregnated fibers in the mold; and
drying the pressed impregnated fibers to form the refractory article.
10 . The method of claim 9 , wherein the inorganic fibers are selected from polycrystalline wool, aluminosilicate fibers, alumino zirconia silicate fibers, and/or alkaline earth silicate fibers.
11 . The method of claim 9 , comprising impregnating the inorganic fibers with the phosphoric acid.
12 . The method of claim 9 , comprising impregnating the inorganic fibers with the at least one colloidal inorganic oxide, wherein the at least one colloidal inorganic oxide comprises colloidal silica, colloidal alumina, and/or colloidal zirconia.
13 . The method of claim 9 , further comprising cutting the refractory article.
14 . The method of claim 9 , comprising impregnating the inorganic fibers with a colloidal solution comprising the at least one colloidal inorganic oxide and a gelling agent.
15 . The method of claim 14 , wherein the at least one colloidal oxide comprises colloidal silica and the gelling agent comprises ammonium acetate, calcium chloride, magnesium chloride, magnesium oxide, acetic acid, hydrochloric acid, phosphoric acid, or combinations thereof.
16 . The method of claim 9 , wherein the refractory article has at least one of the following properties:
(i) a density of 500 kg/m 3 to 1500 kg/m 3 ;
(ii) a thermal conductivity of 1.0 Wm/K or less at 700° C.; and/or
(iii) a linear thermal shrinkage at 1400° C. of less than 2.5%.
17 . The method of claim 9 , wherein the refractory article has the following properties:
(i) a density of 500 kg/m 3 to 1500 kg/m 3 ;
(ii) a thermal conductivity of 1.0 Wm/K or less at 700° C.; and
(iii) a linear thermal shrinkage at 1400° C. of less than 2.5%.
18 . A support plate for a furnace comprising the refractory article of claim 1 .
19 . An insulating brick for lining a furnace comprising the refractory article of claim 1 .
20 . A backup plate for ladle, torpedo car, trough runner, tundish or mold comprising the refractory article of claim 1 .