I am indeed pleased to prepare this brief foreword for this book,
written by several of my friends and colleagues in the Soviet Union. The
book was first published in the Russian language in Moscow in 1975. The
phenomenon of superconductivity was discovered in 1911 and promised to
be important to the production of electromagnets since superconductors
would not dissipate Joule heat. Unfortunate- ly the first materials
which were discovered to be superconducting reverted to the normal
resistive state in magnetic fields of a few tesla. Thus the development
that was hoped for by hundredths of a the early pioneers was destined to
be delayed for over half a century. In 1961 the intermetallic compound
NbaSn was found to be superconducting in a field of about 200 teslas.
This breakthrough marked a turning point, and 50 years after the
discovery of superconductivity an intensive period of technological
development began. There are many applications of superconductivity that
are now being pursued, but perhaps one of the most important is super-
conducting magnetic systems. There was a general feeling in the early
1960s that the intermetallic compounds and alloys that were found to
retain superconductivity in the presence of high magnetic fields would
make the commercialization of superconducting magnets a relatively
simple matter. However, the next few years were ones of disillusionment;
large magnets were found to be unstable, causing them to revert to the
normal state at much lower magnetic fields than predicted.