Low-fired ceramics

Deteriora.tlon. Ceramic objects are fragile, and mechanical damages through breakage and abrasions are the most likely source of destmction. Low fired ceramics can suffer through the rehydration of the body material this process results ia a complete loss of mechanical streagth. The preseace of soluble salts ia porous ceramic bodies has the same disastrous results as ia stoae (136). 

In-plant impregnation of low-fired ceramic products. Low-fired ceramic products such as roof tiles, facing tiles and unglazed floor tiles are made water repellent by immersing them in dilute silicone masonry water repellents thereby preventing efflorescence and imparting water repellency (Wacker-Chemie, 1982). Prefabricated concrete components, plaster of paris and aerated concrete can also be treated in this way. 

W. A. Vitriol andj. I. Steiaberg, "Development of a Low Fire Cofired Multilayer Ceramic Technology," 1983, pp. 593—598. 

Pricing as well as reliability considerations have led to an almost exclusive use of Si-based (i.e. Si and SOI) micro machined devices. Packaging and assembly has focused on ceramics (A1203, AIN, Low Temperature Co-fired Ceramics LTCC), Printed Circuit Board (PCB-) and Surface Mount Device (SMD-) technology and multichip modules (MCM s). 

LIGA lithographie, galvanoformung, abformtechnik LTCC low-temperature co-fired ceramics MEMS microelectromechanical systems... 

LTCC low-temperature co-fired ceramic (an aluminum borosilicate) Luminol 5-amino-2,3-dihydro- 1,4-phthalazinedione... 

Over the past two decades MLC technology has been progressively developed for advanced packaging, especially by main frame computer manufacturers, and it is increasingly exploited for microwave communications. Especially significant is the emergence of low temperature co-fired ceramic (LTCC) technology. 

Longtu, Li. et al. (1990) Lead zirconate titanate ceramics and monolithic piezoelectric transformer of low firing temperature, Ferroelectrics, 101, 193-200. 

The latter reaction can form long chain phosphates, where n is theoretically infinite. Being formed by heat treatments, these phosphates are excellent candidates for high-temperature ceramics and glasses. Because the subject of this volume is low-temperature ceramics, we will not discuss the condensed phosphates in detail, except in one case in Chapter 15, where cements for geothermal wells are discussed with sodium metaphosphate. However, bear in mind that CBPCs can be precursors to high temperature phosphates and glasses. For this reason, as we have seen in the literamre survey presented in Chapter 3, early interest in CBPCs was the formation of refractory shapes at room temperature, which were then fired to produce the final refractory components. 

Low thermal expansion coefficient matching that of the co-fired ceramic capsule. 

Ceramics can be classified by considering the firing temperature and the resulting porosity thus high-fired stoneware (produced at above 1000°C) has porosities less than 2% and low-fired earthenware (firing between 600 and 900°C) with far more than 10% porosity are at the upper and lower ends of the scale. Porcelain (defined as white and translucent ceramic, fired up to 1400°C) can exhibit an extremely low porosity, whereas terracotta or raku (both fired below 1000°C) would be examples of high porosity. 

M. Z. Jhou, J. H. Jean, Low-Fire Processing of Microwave BaTi409 Dielectric with BaO-ZnO-B203 Glass,/. Am. Ceram. Soc., 89, 786-91 (2005). 

H. Kagata, T. Inoue, J. Kato, I. Kameyama, Low-Fire Bismuth-Based Dielectric Ceramics for Microwave Use, Jpn. J. Appl. Phys., 31, 3152-55 (1992). 

Yonezawa, M., Low-firing multilayer capacitor materials, Am. Ceram. Soc. Bull., 62, 1375 (1983). 

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