A basic gunning material interfaces study

Corrosion mechanisms of various basic gunning materials were investigated u sing crucible tests. The low corrosion resistance of olivine-containing mat erials was shown to be related to melted phases formation which occurs, at the gunning material/slag interface, at high temperature. MgO-rich material s are mon resistant to basic slag attack. Moreover, increasing the refracto ry material CaO content by means of dolomite addition rises the slag penetr ation resistance and lowers the bulk modification resulting from slag inter action. In these materials, the corrosion mechanism involves a slag reactio n with the starting binder, (NaPO3)(n), and dolomite initially contained in the gunning material. A dolomite-containing material was projected on slag -covered MgO-C bricks, using a laboratory test equipment. Investigations ca rried out at the gunned material/slag/bricks interface show that the suitab le silicophosphate bond still forms, at interface, despite slag interaction . (C) 2000 Elsevier Science Ltd. All rights reserved.