摘要:
A process is disclosed for simple and rapid production of a shaped body comprising fused silica and a shaped body which leads to virtually no contamination of a melt in contact with the shaped body even at high temperatures. The disclosed process comprises the steps of: a) provision of fused silica in the form of essentially amorphous SiO2 grains of which not more than 5% have a diameter greater than 15 mm, b) addition of water to the fused silica grains to produce a slip, c) casting of the slip into a mold which comprises a hollow body having the inverse shape of the shaped body to be produced, and d) drying of the slip to give an intermediate body, which is then sintered and cooled. A shaped body producible in accordance with the aforementioned process is also disclosed, which comprises at least 99.0 mol % of SiO2.
摘要:
To provide a material for use at high temperatures of several 100° C. which is simple and quick to produce, the invention provides a composite having a layer structure and a process for producing it, which comprises the following steps: a) provision of at least two plates which each have at least one main area of extension, b) stacking of the plates in such a way that a main area of extension of one plate is essentially opposite a main area of extension of the subsequent plate in the stack, c) joining of the stacked plates to form a block using a sinterable composition, d) carrying out a heat treatment on the block so that at least sintering of the sinterable composition occurs and a strong composite body is formed from the block.
摘要:
To provide a material for use at high temperatures of several 100° C. which is simple and quick to produce, the invention provides a composite having a layer structure and a process for producing it, which comprises the following steps: a) provision of at least two plates which each have at least one main area of extension, b) stacking of the plates in such a way that a main area of extension of one plate is essentially opposite a main area of extension of the subsequent plate in the stack, c) joining of the stacked plates to form a block using a sinterable composition, d) carrying out a heat treatment on the block so that at least sintering of the sinterable composition occurs and a strong composite body is formed from the block.
摘要:
For simple and rapid production of a shaped body comprising fused silica and a shaped body which leads to virtually no contamination of a melt in contact with the shaped body even at high temperatures, the invention provides a process comprising the steps: a) provision of fused silica in the form of essentially amorphous SiO2 grains of which not more than 5% have a diameter greater than 15 mm, b) addition of water to the fused silica grains to produce a slip, c) casting of the slip into a mould which comprises a hollow body having the inverse shape of the shaped body to be produced, d) drying of the slip to give an intermediate body, e) sintering of the intermediate body at a sintering temperature at which at least part of the fused silica is transformed from the amorphous modification into a crystalline modification, f) cooling of the sintered shaped body to a temperature below 300° C., so that a microstructure containing crystalline SiO2 is formed, and also a shaped body which comprises at least 99.0 mol % of SiO2.