摘要 |
Refractory comprises grog and hydraulic or chemical binder and contains even distributions of heat-resistant fibre and individual pieces of cutting resistant material. Pieces have hardness of at least 7 and are pref. carbides, nitrides, borides, hard metals or Al2O3 - based materials; size is 5-20 and esp. 10-15 mm. - Fibre is pref. steel or carbon present at up to 10 wt.% and is up to 10 cm long x 0.1-0.5 mm dia. Pref. grog is alumina, bauxite, kaolin, aluminosilicate, chromite, ZrO2 or olivine and binder is Ca aluminate cement, phosphoric acid/ phosphates, silicate cement, colloidal silica or silica or alumina with particle size below 10 micron. Pref. compsn. is lapha corundum grog, Ca aluminate cement, steel fibre 2-5 cm long x 0.2-0.3 mm dia. and 10-15 mm SiC. |