| 摘要 |
A refractory article for use in casting operations wherein said article is subject to prolonged contact with molten metal of at least 1500°C for at least three hours, said article comprises a ceramic composite consisting essentially of about 10 to about 40 wt. % mullite about 35 to about 5 wt. % aluminium nitride and at least about 20 wt. % boron nitride, for forming a reactive coating layer covering at least 80% of exposed surfaces and providing corrosion / erosion protection for said article against molten metal. |
