Joining ceramic-to-metal

Joining of ceramic materials should only involve materials with similar properties. Especially the thermal expansion coefficient is a crucial point when either joining ceramic materials to each other or, even worse, joining ceramics to metals. Figure 2.15 shows an example of a ceramic microstructure device connected to metal flanges and fittings. 

Joining. The term is particularly applied to the technology required to bond similar or dissimilar materials to form components for mechanical or electrical engineering applications. It is especially used of joining ceramics to metals in machine parts. 

Why are special precautions necessary when joining ceramic components to metal components What methods are available for the satisfactory joining of ceramics to metals ... 

Naka M, Maeda M (1991) Application on ultrasound on joining of ceramics to metals. Eng Fract Mech 40(4-5) 951-956... 

High-temperature joining of ceramics and of ceramics to metals... 

There are several possible ways of accomplishing this. These include localized cooling at the joining area, mechanical seal (such as Swagelok), ceramic-to-ceramic, ceramic-to-metal seals (cermets), gland packing, and special types of seals. 

G. Partridge, Joining Glass-Ceramics to Metals, in Joining cf Ceramics, M. G. Nicholas ed.. Chapman and Hall, London, New York (1990) 31-55. 

Many techniques are available for joining ceramics to other ceramics or to metals. The review of ceramic joining by Suganuma et al. and an earlier review by Rice provide a more detailed overview. 

It is important to study the wetting behavior of metal or glass Uquids to a ceramic material. For instance, the joining of ceramics to metals by active metal brazing depends on the wetting of the ceramic by the braze filler. In the electronics industry. 

Ceramics are joined to metals by metal eoating and brazing, and by the use of adhesives. In metal coating, the mating face of the ceramic part is coated in a thin film of a refractory metal such as molybdenum (usually applied as a powder and then heated). 

Therefore, a team, led by the University of Alaska-Fairbanks, was formed to study these practical issues (75), including the composition of the ceramic membrane, seals that would join the ceramic and metal materials, membrane performance, and development of a ceramic that would resist warping and fracturing at the high temperatures of the conversion process. 

Nagy, P. B. and Adler, L. (1989). On the origin of increased backward radiation from a liquid-solid interface at the Rayleigh angle. J. Acoust. Soc. Am. 85,1355-7. [116] Narita, T., Miura, K., Ishikawa, I., and Ishikawa, T. (1990). Measurement of residual thermal stress and its distribution on silicon nitride ceramics joined to metals with scanning acoustic microscopy. /. Japan. Inst. Metals 54,1142-6. [148]... 

Shrinking is a so-called mechanical bonding technique. Two hot objects are fitted together. When they cool the outer part attaches itself to the inner one. For this to be possible the outer part must have a bigger thermal expansion coefficient than the inner one. In this way ceramics and metals can be joined. 

The same capillary phenomena affect brazing practice for joining both ceramic and metal components, but the relative importance of the phenomena differs, and this makes it convenient to discuss their effects in a different sequence. Further, most joining of ceramics is to metals and the different thermal expansion and mechanical characteristics of these two families of materials, as exemplified in Table 10.4, have a profound effect on joint design that is not related to capillarity. 

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