| 摘要 |
<p>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 surfaceparts 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 prefabricated metal member may also be a thin metal coating which is to end up as an exterior coating of the body and which has been applied on a smooth surface of a member which is removable, such as by melting or chemical treatment. Thereby, exact thin metal surfaces may be provided on e.g. concrete-like bodies. The mouldable material is, in particular, a material which in its cured state comprises a coherent matrix, the matrix comprising a) homnogeneously arranged solid particles of a size of from about 50 A^o to about 0.5 νm, or a coherent structure formed from such homogeneously arranged particles, and B) densely packed solid particles having a size of the order of 0.5 - 100 νm 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 homogeneously 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 concrete. 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.</p> |
