The invention relates to the technical field of
refractory bricks, in particular to a
phosphate combined light-burned high-
alumina brick for a high-
erosion-resistance Mannheim furnace
hearth, which is prepared from the following raw materials in parts by weight: 30 to 35 parts of homogenized
alumina, 35 to 40 parts of calcined
alumina, 8 to 10 parts of
ball clay, 1.5 to 2 parts of mixed liquor, 4 to 6 parts of aluminum dihydrogen
phosphate solution and 10 to 15 parts of filler. According to the invention, after
zircon in the base material is activated by dilute
nitric acid and modified by a
silane coupling agent, the surface activity is improved, the
zircon and a
phosphate binding agent generate strong chemical bonding, nano
zirconium oxide in the auxiliary material forms a stable
crystal structure after
hydrothermal synthesis and high-temperature
calcination, and the base material and the auxiliary material are tightly combined in the mixing process; uniformly distributed reinforcing units are formed in the matrix, and through double mechanisms of physical filling and interface chemical bonding, the densification degree and integrity of the matrix are remarkably improved, so that the
permeation path of a corrosive medium is effectively blocked, and the long service life of the material is ensured.