GB528907A - Improvements in or relating to the manufacture of metal mosaics - Google Patents

Abstract

528,907. Metal mosaics. STEVENS, A. H. (Handy & Harman). May 2, 1939, No. 13092. [Class 20 (iv)] [Also in Groups XV and XXII] Metal mosaics, particularly for ornamental objects such as jewellery, are formed by assembling a plurality of small metallic bodies, some or all of which are constituted by partially sintered powdered metal, metals, or alloys, and uniting them by heating the assembly with or without simultaneous or subsequent pressure. As applied to the production of a mosaic of silver and copper bodies, powdered silver and powdered copper are placed in separate moulds and partially sintered by the simultaneous application of heat and pressure below those requisite to complete sintering, so as to form blocks which can easily be formed into pieces by sawing, filing, cutting or abrading. These blocks are then separated into pieces of the desired size-and shape which are assembled to form the mosaic pattern; the assembly is placed in a mould and subjected to the simultaneous application of heat and pressure, the temperature and pressure, preferably, being higher than the temperature and pressure employed in the partial sintering process. If desired, the partial sintering process may be varied by first compressing the powdered metal, without heat, and thereafter heating the block with or without pressure. Instead of hot-pressing the assembled mosaic pieces, these may be heated without pressure to a temperature sufficient to consolidate the pieces, or the pieces may be first heated and afterwards pressed. The mosaic may be provided with a backing which may be a cast and rolled metal or alloy, or a sintered metal; in either case, the mosaic pieces are arranged on the backing-plate and the whole assembly is then placed in a mould and subjected to heat, with or without pressure. If desired, the mosaic may comprise cast and rolled metal pieces as well as the partially sintered metal bodies.