Patent ID: 8999091
Filing Date: 2015-04-07
Classification: B32B,C03C,C04B,Y10T

Abstract:
1. A process for producing a composite body of an apparatus that comes into contact with a glass or semiconductor melt, the process comprising: a) providing more than two plates, with each plate having at least one main area of extension, wherein at least one of the plates comprises sintered silica, and wherein a plate thickness of at least one of the plates is in the range from 10 mm to 100 mm, b) stacking the plates with formation of intermediate spaces in such a way that the main area of extension of one plate is essentially opposite the main area of extension of the subsequent plate in the stack, and wherein a gap width of the intermediate spaces is in the range from 10 mm to 50 mm, c) joining the stacked plates to form a block using a sinterable composition, and d) strengthening the block by carrying out a heat treatment on the block so that at least sintering of the sinterable composition occurs, wherein the composite body is formed from the block; wherein the plates themselves are produced by a process comprising the steps: wherein the plates are subjected after step cc) and/or after step dd) to ff) sintering, wherein the sintering in step ff) is carried out at a sintering temperature at which at least part of the fused silica is transformed from the amorphous modification into a crystalline modification in the temperature range with commencement of cristobalite formation such that the composite body has a microstructure with grains being joined to one another via sintered bridges and comprising amorphous fused silica with SiO the composite body showing after sintering a bulk density of 1.95 g/cm wherein the composite body produced by the process comprises a contact surface, and wherein the contact surface of the composite body comes into contact with the glass or semiconductor melt.