| 摘要 |
The characteristics of surfaces of bodies made from a basic material (22) which is mouldable at low temperatures, such as concrete or concrete-like materials are improved by applying a layer of metal (12) to one or more surface parts thereof. The metal layer may be applied by moulding the basic material, optionally with reinforcements (23) against a prefabricated metal member (12) which may be a metal layer formed on a surface (21) of a model or a mould (20) whereby a metal-coated tool for casting or shaping articles corresponding to the model or mould may be made from the basic material. The mouldable material is, in particular, a material which in its cured state comprises a coherent matrix, the matrix comprising (A) homogenously arranged solid particles of a size of from about 50 ANGSTROM to about 0.5 mu m, or a coherent structure formed from such homogenously arranged particles, and (B) densely packed solid particles having a size of the order of 0.5-100 mu m and being at least one order of magnitude larger than the respective particles stated under (A), or a coherent structure formed from such densely packed particles, the particles A or the coherent structure formed therefrom being homogenously distributed in the void volume between the particles B, the dense packing substantially being a packing corresponding to the one obtainable by gentle mechanical influence on a system of geometrically equally shaped large particles in which locking surface forces do not have any significant effect, optionally additionally comprising, embedded in the matrix, (C) compact-shaped solid particles of a material having a strength exceeding that of ordinary sand and stone used for ordinary conrete. Example of such a material is one in which the particles A are silica dust having a specific surface of about 250,000 cm2/g, the particles B are cement particles, and the bodies C are refractory grade bauxite.
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