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This was the third meeting in the series of special topical
conferences on Non-Metallic materials at low temperatures. The
first meeting was in Munich in 1978, the second in Geneva (1980)
and so Heidelberg 1984 seemed an obvious time to review some of the
hopes and objectives of the earlier meetings. It is also
appropriate to consider the changing needs of the cryogenic
community and how best the theory and practice of Non-metallic
materials can be applied to suit this dynamic young science. The
aims and objectives of the International Cryogenic Materials Board
in sponsoring this meeting remain the same. Namely, to provide a
forum where practicing Engineers can meet with materials suppliers
and researchers in an attempt to ensure that a real understanding
exists between the two sides of the Cryogenic Materials Community.
In this atmosphere, real problems can be addressed together with
full discussions of tried and tested practical solutions. It is in
this way that knowledge and confidence may grow hand in hand with
the logical growth of the industry.
Cryogenics is an emerging technology filled with promises. Many
cryogenic systems demand the use of nonmetallics and composites for
adequate or increased performance. Thermal and electrical
insulations, potting for superconducting magnets' mechanical sta
bility, and composite structures appear to be some of the most
significant applications. Research on nonmetallics at cryogenic
temperatures has not progressed to the degree of research on
metals. Nor can room temperature research be extrapolated to low
tempera tures; most polymers undergo a phase transformation to the
glassy state below room temperature. Research by producers, for the
most part, has not been prac tical, because, except for LNG
applications, the market for large material sales is not imminent.
There are, however, many government stimulated developmental
programs. Research on nonmetallics thus is dictated by development
project needs, which require studies orien ted toward prototype
hardware and specific objectives. As a result, research continuity
suffers. Under these conditions, periodic topical conferences on
this subject are needed. Industry and uni versity studies must be
encouraged. Designers and project research material specialists
need to exchange experiences and data. Low temperature-oriented
research groups, such as the National Bureau of Standards and the
Institute for Technical Physics - Karlsruhe, must contribute by
assisting with fundamentals, interpreting proj ect data, and
contributing to project programs through their materials research."
Most descriptions of polymers start at room temperature and end at
the melting point. This textbook starts at very low temperatures
and ends at room temperature. At low temperatures, may processes
and relaxations are frozen which allows singular processes or
separate relaxations to be studied. At room temperatures, or at the
main glass transitions, many processes overlap and the properties
are determined by relaxations. At low temperatures, there are
temperature ranges with negligible influences by glass transitions.
They can be used for investigating so-called basic properties which
arise from principles of solid state physics. The chain structure
of polymers, however, requires stringent modifications for
establishing solid state physics of polymers. Several processes
which are specific of polymers, occur only at low temperatures.
There are also technological aspects for considering polymers at
low temperatures. More and more applications of polymeric materials
in low temperature technology appear. Some examples are thermal and
electrical insulations, support elements for cryogenic devices,
low-loss materials for high frequency equipments. It is hoped that,
in addition to the scientific part, a data collection in the
appendix may help to apply polymers more intensively in low
temperature technology. The author greatly appreciates the
contributions by his coworkers of the Kernforschungszentrum
Karlsruhe in measurement and discussion of many data presented in
the textbook and its appendix. Fruitful disccussions with the
colleagues Prof. H. Baur, Prof. S. Hunklinger, Prof. D. Munz and
Prof. R."
Most descriptions of polymers start at room temperature and end at
the melting point. This textbook starts at very low temperatures
and ends at room temperature. At low temperatures, may processes
and relaxations are frozen which allows singular processes or
separate relaxations to be studied. At room temperatures, or at the
main glass transitions, many processes overlap and the properties
are determined by relaxations. At low temperatures, there are
temperature ranges with negligible influences by glass transitions.
They can be used for investigating so-called basic properties which
arise from principles of solid state physics. The chain structure
of polymers, however, requires stringent modifications for
establishing solid state physics of polymers. Several processes
which are specific of polymers, occur only at low temperatures.
There are also technological aspects for considering polymers at
low temperatures. More and more applications of polymeric materials
in low temperature technology appear. Some examples are thermal and
electrical insulations, support elements for cryogenic devices,
low-loss materials for high frequency equipments. It is hoped that,
in addition to the scientific part, a data collection in the
appendix may help to apply polymers more intensively in low
temperature technology. The author greatly appreciates the
contributions by his coworkers of the Kernforschungszentrum
Karlsruhe in measurement and discussion of many data presented in
the textbook and its appendix. Fruitful disccussions with the
colleagues Prof. H. Baur, Prof. S. Hunklinger, Prof. D. Munz and
Prof. R."
This was the third meeting in the series of special topical
conferences on Non-Metallic materials at low temperatures. The
first meeting was in Munich in 1978, the second in Geneva (1980)
and so Heidelberg 1984 seemed an obvious time to review some of the
hopes and objectives of the earlier meetings. It is also
appropriate to consider the changing needs of the cryogenic
community and how best the theory and practice of Non-metallic
materials can be applied to suit this dynamic young science. The
aims and objectives of the International Cryogenic Materials Board
in sponsoring this meeting remain the same. Namely, to provide a
forum where practicing Engineers can meet with materials suppliers
and researchers in an attempt to ensure that a real understanding
exists between the two sides of the Cryogenic Materials Community.
In this atmosphere, real problems can be addressed together with
full discussions of tried and tested practical solutions. It is in
this way that knowledge and confidence may grow hand in hand with
the logical growth of the industry.
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